Congenital Anomaly Register & Information Service for Wales Ann rep (Eng... · 2015-10-27 · 2 | annual review CONGENITAL ANOMALY REGISTER & INFORMATION SERVICE Foreword 3 CARIS

Congenital Anomaly Register & Information Service for Wales

inside...

10 years of reporting...

10 years of CARIS data page4

Antenatal detection page16

Screening services in Wales page26

CAR Sonline ar-y-we

2 | annual review CONGENITAL ANOMALY REGISTER & INFORMATION SERVICE

Foreword 3

CARIS activity 2007 5

Patterns of anomalies in Wales 8

Congenital anomalies and deprivation 14

Antenatal detection in Wales 18

Health Service Provision 24

Screening services in Wales 26

Antenatal Screening Wales 26

Newborn Screening Wales 27

Newborn Hearing Screening Wales 30

Appendix A: How CARIS operates 32

Appendix B: ‘Top 25’ conditions 33

Appendix C: CARIS data on some rare syndromes 34D

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Contents

Welcome to the 2007 CARISannual review. This year we areable to report on a full ten years ofCARIS data. In the report we usethis information to illustrate howCARIS’ aims are achieved.

This year three guest contributorsfrom the world of screening explain their roles in Wales.

Detailed data tables are availablefrom the CARIS website onwww.wales.nhs.uk/caris

Thank you very much to allcontributing health professionalsfor their continuing support.

We would also like to thank thefollowing who have helped withproduction of this report

Tracy Price, Hugo Cosh andGareth Davies of the HealthInformation and Analysis Teamof the National Public HealthService for Wales who haveundertaken the main annual data analysis

Kerry Bailey who has preparedthe work on anomalies anddeprivation

Margery Morgan, Lead Clinician Judith Greenacre, Director ofInformation David Tucker, CARIS Manager

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* also accessible through the HOWIS (NHS Wales) website at www.howis.wales.nhs.uk/caris

Write CARIS OfficeLevel 3 West WingSingleton HospitalSWANSEASA2 8QA

Phone 01792 285241(WHTN 0 1883 6122)

Fax 01792 285242(WHTN 0 1883 6123)

e-mail [email protected]

web www.wales.nhs.uk/caris

Published by CARIS ISBN 0-9537080-X

© CARIS 2008

CAR Sonline ar-y-we

Foreword

The CARIS team at the 2007 South Wales Annual Meeting.

We are (left to right) David Tucker, Val Vye, Judith Greenacre,Margery Morgan and Helen Jenkins.

CARIS, the Congenital Anomaly Register andInformation Service for Wales, is based at SingletonHospital, Swansea. It is funded by the Welsh AssemblyGovernment and is part of NHS Wales.

CARIS is the Welsh Congenital AnomalyRegister and Information Service.

CARIS aims to provide reliable data oncongenital anomalies in Wales. These dataare used to assess –

Patterns of anomalies in Wales

Possible clusters of birth defects and their causes

Antenatal screening / interventions

Health service provision for affectedbabies and children.

Ten years of data are now available. This year we have looked in greater detailat the patterns of anomalies in Wales. Key points are –

The gross1* rates of congenitalanomalies reported is 4.9%.

The rate of congenital anomalies in live born babies is 4.2%

85% of cases are live born and 96%of these survive to the end of theirfirst year. Survival is reduced withincreasing complexity of anomalies

Congenital anomaly rates in Walesare often apparently higher than forother areas of Europe or Britain

Variations in rates are again seenaround Wales. In part this is due todifferences in reporting

Factors shown to affect anomalyrates include maternal risk factorssuch as age and smoking. There isalso an association withsocioeconomic deprivation,particularly for non chromosomalanomalies

Heart and circulatory defects are the largest single group reported,followed by the urinary system andlimb defects

For anomalies detected up to thefirst birthday, approximately one thirdof cases are detected antenatally,one third within the first week afterend of pregnancy, and the remainingthird later in infancy

Some specific anomalies continue to be investigated because ofparticularly high rates in Wales.These include gastroschisis andisolated cleft palate.

We have assessed antenatal screening and looked at health provision to detectcongenital anomalies. Key points are –

Rates of antenatal detection areimproving in Wales

Outcome data can be useful inplanning services and for parentinformation.

In our 2008 annual meetings we will belooking at future developments for mothersand babies affected by congenitalanomalies. For the future of CARIS we willwork towards achieving during the next ten years –

Better surveillance

A maternity information system ableto provide good denominator data.


Summary

1* The gross rate includes all cases of anomalyrecorded as miscarriages, terminations ofpregnancy, live and stillborn babies

The team continued to be involved withprojects in Wales, the United Kingdomand internationally.

Wales• The new RadIS II obstetric reporting

module was piloted in Royal GlamorganHospital. This has enabled CARIS to haveeasy access to antenatal ultrasound data.When an ultrasonographer finds asuspicion of an abnormality the details aresaved to be reported specifically to CARIS.We also have the opportunity to checkpostnatal scans in certain babies forexample in those with dilated renal pelves.The plan in Wales is for all units to use theobstetric reporting module and this shouldimprove case ascertainment for CARISand the assessment of antenataldetection.

• The Welsh Paediatric Surveillance Unitagreed to investigate craniosynostosis forCARIS. This involves a regular reminder topaediatricians in Wales asking for detailsabout the condition. CARIS chose to focuson craniosynostosis as this is a conditionnot normally detected antenatally. We were concerned that we were missingcases and unable to provide reliable dataon prevalence rates and outcomes. Theproject is planned to run until the end of2008.

• Data from the register was presented atthe International Congress of Obstetricsand Gynaecology, London in July 2007looking at the increased rates ofhypospadias in mothers treated withclomiphene to induce ovulation.

• Annual meetings were held in UniversityHospital of Wales, Cardiff andBodelwyddan Castle, Rhyl. The focus forthese and the annual report was riskfactors in the development of congenitalanomalies.

• CARIS has been part of an assessment ofPublic Health functions in Wales organisedby the Welsh Assembly Government,looking at different managementarrangements.

• Improved access to inpatient (PEDW) andchild health data from Health SolutionsWales has contributed to better and moretimely case ascertainment. PEDW capturesdetails of babies who may have not beendiagnosed at birth but require admission fortreatment or surgery later.

United Kingdom• CARIS continues to contribute to the

British Isles Network of CongenitalAnomaly Registers (BINOCAR) executivegroup.

• David Tucker chaired the BINOCAR clinicalcoding working group which hasdeveloped a coding framework to achieveconsistency in coding of congenitalanomalies across the UK.

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CARIS activity 2007

International• CARIS presented Welsh data on

gastroschisis at the International ClearingHouse of Birth Defects Surveillance andResearch (ICBDSR) conference in Italy.

• David Tucker joined the coding committeeand a working group to advise on theInternational Clearing House annual report.

• As well as supplying annual anomaly datawe continue to submit enhancedanonymised data to the ICBDSR rarediseases programme.

• CARIS presented data on the antenataldetection of congenital heart anomalies atthe Naples meeting of the EuropeanCollaboration of Congenital AnomalyRegisters (EUROCAT).

• We continued to contribute to a WHOworldwide study on orofacial clefting.

Websiteswww.binocar.org

www.eurocat.ulster.ac.uk

www.icbdsr.org

Publications in 2007 usingCARIS dataGarne E, Loane M, Dolk H and aEUROCAT Working Group (2007),"Gastrointestinal Malformations: Impact of Prenatal Diagnosis on Gestational Ageat Birth", Paediatric and PerinatalEpidemiology, Vol 21, pp 370-375.

Loane M, Dolk H, Bradbury and aEUROCAT Working Group (2007),"Increasing Prevalence of Gastroschisis in Europe 1980-2002: A PhenomenonRestricted to Younger Mothers?",Paediatric and Perinatal Epidemiology, Vol 21, pp 363-369.

CARIS activity 2007


CARIS began data collection on 1st January 1998. This report looks at thefirst ten years of information that CARIS has provided, to 31st December 2007.

The aims of CARIS are to provide reliabledata on congenital anomalies in Wales.These data are used to assess:

• patterns of anomalies in Wales

• antenatal screening / interventions

• health service provision for affectedbabies and children

• possible clusters of birth defects andtheir causes.

For this report, these uses of data havebeen grouped into two sections

• Describing patterns of anomalies andidentifying causes for concern suchas high rates or clusters

• Using data to assess interventionsand services, particularly antenatalscreening for congenital anomalies.

More details of the methods used by CARISto collect, process and disseminate dataand information are given in Appendix A.

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Ten years of CARIS data

Rates of congenital anomaliesin Wales

Overall ratesIt is thought that about 30% of allconceptions are affected by some form of congenital anomaly. The vast majority ofthese miscarry spontaneously and may notcome to the attention of health services.

CARIS data (1998 - 2007) suggest that:

• About 5% of established pregnanciesare affected by congenital anomaly.Some of these will result in miscarriageor termination of pregnancy followingantenatal detection of defects.

• 4.2% of live born babies will have acongenital anomaly, although not all of these will be detected by the time of birth.

Variations in rates around WalesAcross Wales, there are significantdifferences between Unitary Authorities in reported rates of anomalies (Figure 1).Swansea and Neath Port Talbot havetraditionally shown higher rates thanelsewhere in Wales and this reflectsexcellent reporting in these areas. Blaenau Gwent and Cardiff have alsoshown good reporting and have also hadhigher rates in recent years. The difficultyis in differentiating high rates due to goodreporting from genuinely higher rates in theoccurrence of anomalies. CARIS hopes towork with the NPHS in the coming year tofind better ways to report variations inrates across Wales.

Figure 1: Comparison of gross rates ofanomaly for Welsh Unitary Authorities withall Wales average.

Types of congenital anomalyCARIS classifies anomalies by the bodysystem that is mainly affected. Rates forthese anomaly groups are shown in Figure 2. Cardiovascular anomalies are thelargest group, followed by anomalies of the urinary system and then limb defects.

Figure 2: Main anomaly groups for casesreported to CARIS 1998-2007, rate per10,000 total births. Source: CARIS, ONS



Significantly higher

Comparable

Significantly lower

Crown copyright material is reproduced with the permission of the Controller of HMSO and the Queen’s Printer for Scotland

0 20 40 60 80 100 120 140

NeurologicalEye/Ear

CirculatoryRespiratory

DigestiveUrinaryGenital

Endocrine, metabolicBlood, immune, lymphatic

SkinLimbs

MusculoskeletalNeoplastic

Genetic/multi-site disorders

gross rate per 10,000 total births

More data on individual types of anomalyare available from the CARIS website. Someinformation about the ‘top 25’ anomaliesreported to CARIS are given in Appendix B.These have been chosen because they arecommon or of particular clinical or publichealth importance. In general, rates are atleast as high as those reported fromcomparable registers elsewhere in Europeand the Western world. In many casesCARIS rates are higher. Some of thisreflects differences in the way data isreported, together with the excellentreporting we enjoy in Wales.

Some anomalies are extremely rare and,even with ten years of data, numbersreported to CARIS are small. Examples of rare syndromes detected in livebornbabies are given in Appendix C.

Patterns of anomaliesA baby may have a single anomaly or acomplex pattern of defects affecting manydifferent body systems. The pattern ofanomalies, together with a thoroughknowledge of embryology, can in somecases help point to possible causes foranomalies. For cases reported to CARIS:

• Over half of cases have a single anomaly

• Over a third have an anomaly affectingmore than one body system or anunderlying syndrome

• About 10% have a chromosomalanomaly

Demographic featuresGestational ageMost babies reported to CARIS are liveborn at the end of a normal lengthpregnancy (Figure 3). However, there is asmaller peak of fetuses with pregnancyending at 16-22 weeks gestation aftertermination of the pregnancy followingantenatal detection of defects.

Figure 3: Congenital anomalies, outcome ofpregnancy by gestational age, 1998-2007.Source: CARIS

Maternal ageMaternal age plays a significant influence on the numbers and types of congenitalanomaly that occur. CARIS data showshow maternal age distributions for babieswith anomalies vary from those for babieswithout anomalies (Figure 4).

Figure 4: Rates of congenital anomaliesreported by CARIS, by maternal age group,1998-2007. Source: CARIS, ONS

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Greater proportions of mothers of babieswith chromosomal syndromes are in the35+ age groups compared to the generalpopulation of expectant mothers. This is dueto the increasing incidence of chromosomalanomalies with advancing maternal age. Incontrast, gastroschisis (a defect of theanterior abdominal wall) occurs morecommonly in babies born to youngermothers. The reasons for this are unknown.

CARIS data has been used to calculatethe maternal age related risk of having ababy with Down syndrome (Trisomy 21) in Wales (Figure 5). This shows how therisk of Down syndrome increases withmaternal age. These risk values appear tobe higher than those quoted in theAntenatal Screening leaflet.

Figure 5: Maternal age related risk inWales of having a baby with Downsyndrome (live and stillbirths) from CARISdata 1998 – 2007.

Maternal age group (years) CARIS data

<20 1 in 1033

20-24 1 in 1297

25-29 1 in 916

30-34 1 in 558

35-39 1 in 170

40-44 1 in 58

45+ 1 in 29

Multiple pregnancyPrevious analysis of CARIS data showsthat the relative risk of having a fetusaffected by a congenital anomaly in amultiple pregnancy is 11.4%. This is 2.5times higher than in a singleton pregnancy.

Sex of fetusMore male babies are born each year thanfemale (ONS birth data shows 11 malebabies born in Wales for every 10females). CARIS data shows that this ratiois even greater for babies with congenitalanomalies with 13 male babies for every10 female. CARIS routinely looks at themale to female ratio for anomaliesreported. This shows that the excess inmale babies is mainly associated withdefects of the urinary and genital systems,followed by anomalies of the digestive andmusculoskeletal systems.

Survival of babies withanomaliesCARIS records how each pregnancy endsand, if the baby is live born, whetherhe/she survives to the end of the first yearof life. These data show that about 83% of babies with anomalies survive to theirfirst birthday. Of the remainder, over half(11% of the total) result in termination ofpregnancy with the rest associated withnatural losses during pregnancy or postnatal death (Figure 6).

Figure 6: Congenital anomalies byoutcome of pregnancy, 1998-2006(followed up to end 2007).Source: CARIS



Still born,153

Survived to age one year, 11,968

Spontaneous fetalloss, 385

Legal termination,1,560

Death in first weekof life, 202

Death one weekto one year, 241

Survival outcome varies with the pattern of anomalies (Figure 7). As expected,survival rates are highest for babies withsingle anomalies. As the number andcomplexity of anomalies increases, survivalreduces. Poorer survival is associated withincreased rates of natural losses but alsowith termination of pregnancy followingantenatal detection of anomalies.

Figure 7: Congenital anomalies, outcomeof pregnancy by pattern of anomalies,1998-2006 (followed up to end 2007).Source: CARIS

The CARIS website shows survivaloutcome for individual anomalies. This shows, for example that:

• 90% of cases of anencephaly wereterminated. In ten years there were lessthan ten live births with the condition, ofwhich the majority did not survive forlonger than 24 hours.

• Over 90% of babies with heartconditions were alive at one year of age.

• Hypoplastic left heart used to beuniversally fatal within a few weeks of life. With improved treatment,approximately half of liveborn babies with this condition are recorded assurviving at least to the end of their first year of life.

CARIS data can help give parents betterinformation about how likely their babiesare to survive. However, data is recordedhistorically and should be used cautiouslyin giving prospective predictions on risks to survival when the full picture ofanomalies may not be known. Also, survival is only one outcome ofimportance. CARIS does not collectequally important information to parentsconcerning other illness, intellect or quality of life.

Variation in survival around WalesSurvival rates appear to vary betweenUnitary Authorities in Wales, with the bestsurvival rates in Swansea, Monmouthshireand Neath Port Talbot (Figure 8). This maybe because of the good reporting in theseareas.

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0%10%20%30%40%50%60%70%80%90%

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Legal termination

Singleanomaly(n=8265)

Multipleanomaliessame body

system(n=1870)

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syndromes(n=573)

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different bodysystems(n=2305)

Chromosomalsyndromes(n=1499)

All cases(n=14512)

Death in first week of life Death aged one week to one year

Still born Spontaneous fetal loss Survived to age one year

Figure 8: Survival rates for CARIS cases byUNITARY Authorities in Wales 1998 – 2007.

Stage at which case ofanomaly first suspectedCARIS collects data on when a fetus orbaby is first suspected to have some formof anomaly. This is the earliest date known,regardless of how many anomalies mayhave been identified at a later stage.Figure 9 shows that approximately onethird of cases are first detected antenatally, one third detected in the first week of life and a final third later in infancy. As CARIS only collects data on casesdetected up to the end of the first year,detection rates later in childhood are not estimated.

Figure 9: Reported stage of pregnancy/infancy at which first suspected to have an anomaly, 1998-2007.

Surveillance of congenitalanomaliesCARIS data are used in varioussurveillance programmes that aim todetect a rise in congenital anomaly ratespromptly. These systems look at thenumber of anomalies reported over a setperiod of time and compares to previoussimilar time periods to see if the numberhas changed beyond that which might beexpected through chance variation.

Two main systems use CARIS data:

• The Office for National Statisticsoperates the National CongenitalAnomaly System (NCAS). The systemcompares numbers annually and forthree month time periods. Before CARISwas established, reports to NCAS werepaper based and were known to beincomplete. CARIS established electronicreporting and the presence of theregional register has greatly increasedreporting to this system (Figure 10).



Significantly lower

Comparable

Significantly higher

Crown copyright material is reproduced with the permission of the Controller of HMSO and the Queen’s Printer for Scotland

Compared with Wales

Day 29-1 year afterend of pregnancy,

3,019<24 weeks gestation,

3,752

24 weeks to endof pregnancy, 850

Day 7-28 after endof pregnancy, 1,140

Day 0-6 after endof pregnancy, 4,704

• EUROCAT operates a surveillancesystem using annual data supplied byCARIS. This system looks for changes inpatterns of anomalies over time.

Both systems have their limitations. For example, both require pregnancy tohave finished before cases are reported. A significant number of anomalies are nowreported antenatally (see later) and may beknown up to 6 months before reporting isdue to take place. With the developmentof RadIS II, Wales will soon be in a strongposition to develop antenatal surveillanceof some key anomalies that are easilydetected antenatally and where earlyinvestigation of a potential rise in rateswould be important.

Figure 10: Numbers of cases reported toONS Surveillance system, 1993 - 2007.

Particular concernsOver the past 10 years, CARIS data has highlighted a number of particularconcerns about congenital anomalies in Wales.

Gastroschisis• Gastroschisis is a condition in which

there is failure of normal development ofthe anterior abdominal wall. Abdominalorgans may push out through the defectduring fetal life and prompt surgery isrequired shortly after birth to return theorgans into the abdomen and repair thedefect. CARIS has reported extensivelyon gastroschisis in the past, in relation tothe following.

• The risk factors for the condition – the exact cause of the condition is notclear, however younger maternal ageand smoking are significant risk factorsfor this condition. Low maternal weightand use of recreational drugs are alsostrongly associated with gastroschisis.CARIS data is able to describe many ofthese associations in Wales.

• The prevalence of this condition isknown to be rising, particularly inwestern countries. Wales has some ofthe highest rates in the world and this is not thought to be simply because of good reporting (Figure 11).

• In 2004, CARIS and local cliniciansnoticed a marked rise in rates inBridgend county. A cluster of up to 7 cases was identified and investigatedby a multi-agency team. No obviousreason for the cluster could be identified.CARIS continues to actively monitorcases and to support further researchinto the condition.

annual review | 13

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Figure 11: Gastroschisis in Wales, 1998 - 2007.

Isolated cleft palateClefts or gaps in the lips or palate canoccur if there if a failure of the processesby which different parts of the face fusetogether during the period of 5 to 9 weeksafter conception. Clefts of the lip andpalate can occur either singly or incombination with each other. The CARISreview of 1998 – 2002 data firsthighlighted that rates for isolated cleftpalate in Wales were significantly higherthan rates for comparable areas in Europe.

Analysis of Welsh data suggests that ratesare particularly high in North West Wales(Figure 12). When previously reviewed, no obvious cause for this pattern could befound. With considerable additional datanow available, CARIS hopes to work withthe National Public Health Service forWales to look at this again in the coming year.

Figure 12: Gross rates of isolated cleft palate by Welsh Local Authorities.

Congenital anomalies and deprivationMany studies have shown that peopleliving in the most socioeconomicallydeprived areas have worse levels of healththan those living in the most affluent areas.A wide variety of health outcomes havebeen noted to show this pattern, includinglife expectancy, diabetes, childhoodpedestrian injuries and respiratory disease.Live born infants are more likely to diebefore the age of one in the most deprivedareas2. Some of these differences arerelated to underlying differences in factorssuch as smoking rates, but this does notexplain all the differences seen.



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2 Deprivation and Health, HIAT,NPHS 2004

Socio economic deprivation andcongenital anomaliesIn 2000, Vrijheid et al3 used Eurocat datato investigate the link between landfill sitesand congenital anomalies. This alsodemonstrated an association betweensocioeconomic status and congenitalanomalies in the UK (but not with otherEuropean countries).

• Risk of non-chromosomal anomaliesincreased with increasing socioeconomicdeprivation. The risk for the mostdeprived quintile of the deprivation indexwas 40% higher than for the mostaffluent quintile. Some malformationsubgroups also showed increasing riskwith increasing deprivation: all cardiacdefects, malformations of the cardiacsepta, malformations of the digestive system, and multiple malformations. No evidence for socioeconomic variationwas found for other non-chromosomalmalformation groups, including neuraltube defects and oral clefts.

• In analyses unadjusted for maternal age,the risk of chromosomal anomaliesdecreased with increasing levels ofdeprivation, mainly as a result ofdifferences in the maternal agedistribution between social classes.

Congenital anomalies and deprivationin WalesCARIS has long been interested inassessing whether congenital anomalyrates are associated with socioeconomicdeprivation in Wales. Until now, this hasnot been feasible to study because of anumber of challenges which we have nowbeen able to address.

• Being a new register, the numbers ofcases reported to CARIS and availablefor study were initially small, making itdifficult to detect differences betweenareas with different levels of deprivation.With ten years of data and over 15,000cases reported, this is no longer such a serious issue.

• In order to calculate rates, CARISneeded a special download of birth dataincluding maternal age and the level ofsocioeconomic deprivation occurring inthe area of mother’s residence. This isnot normally available from the Office forNational Statistics without specialpermission. This year we have been ableto obtain suitable anonymised data fromthe National Community Child HealthDatabase.

• Differences in reporting across Walesmay influence the results if betterreporting hospitals are located inparticularly affluent or deprived areas. In order to counter this, we have useddeprivation scores for very local areas(Lower Super Output Areas or LSOAs)and aggregated them up across Walesinto 5 groups from most deprived tomost affluent. Each group does nottherefore relate to any easily definedgeographic area of Wales.

• It is always difficult to know exactly howto measure deprivation. The Welsh Indexof Multiple Deprivation (WIMD) is nowavailable and is used increasingly inanalyses of Welsh data. The factors usedin the index are shown in Figure 13.

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3 M Vrijheid, H Dolk, D Stone, L Abramsky, E Alberman,J E S Scott; Socioeconomic inequalities in risk ofcongenital anomaly Arch Dis Child 2000;82:349-352(May)

Figure 13: Welsh Index of MultipleDeprivation (WIMD).

The Welsh Index of Multiple Deprivation2005 is based on the idea of distinct‘domains’ of deprivation which can berecognised and measured separately. These are:

Income

Employment

Health

Education, Skills and Training

Geographical access to services

Housing

Physical EnvironmentA version of WIMD 2005 with the health domainremoved was used, in order to prevent a circular analysis where health is a factor in both the independent and outcome variables. WIMD 2005 was chosen since, as the independent variable, it relates to the period of outcomes under study more closely than WIMD 2008.

Chromosomal disordersIt is known that mothers in more affluentareas tend to have their babies at olderages than mothers in more deprivedareas. As the prevalence of fetalchromosomal disorders is known toincrease with maternal age, there is anatural tendency for rates of fetalchromosomal disorders to be higher in mothers from more affluent areas. This is demonstrated for Wales by CARISdata (Figures 14 & 15).

Figure 14: Congenital anomalies, medianmaternal age by WIMD fifth, 1998-2007.Source: CARIS/WIMD 2005

Figure 15: Congenital anomalies(chromosomal only), rate per 1,000 birthsby WIMD fifth, 1998-2007Source: CARIS/HSW (NCCHD) / WIMD 2005

When these rates are adjusted formaternal age, the pattern seen usingcrude rates is no longer apparent anddifferences between deprivation 5ths arenot significant (Figure 16).



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Figure 16: Congenital anomalies (chromosomal only), rate per 1,000 births by WIMD fifth, 1998-2007.Source: CARIS/HSW (NCCHD) / WIMD 2005

Non Chromosomal casesFor both crude (Figure 17) and maternalage adjusted data (Figure 18), rates ofcases of non chromosomal anomaliesdrop between the 1st (least deprived) and 2nd deprivation quintiles then risewith increasing levels of deprivation. The most deprived quintile has asignificantly higher rate of non-chromosomal anomalies. The otherquintiles are not significantly different.

Babies born in the fifth most deprivedareas are 13% more likely to have a non-chromosomal anomaly than those in thefifth most affluent areas and 20% morelikely than the second quintile of affluenceand this is significant. This pattern is quitesimilar to that observed by Vrijheid et al.

Many of the causes of congenitalanomalies are not known. Suggestedassociations of non-chromosomalcongenital anomalies include proximity tolandfills, diet, including reduced intake offolic acid and obesity. All of these havebeen found to be more common indeprived areas.

Figure 17: Congenital anomalies (non-chromosomalonly), rate per 1,000 births by WIMD fifth, 1998-2007.Source: CARIS/HSW (NCCHD) / WIMD 2005

Figure 18: Congenital anomalies (non-chromosomal only), rate per 1,000 births by WIMD fifth, 1998-2007.Source: CARIS/HSW (NCCHD) / WIMD 2005

SummaryThe prevalence of non-chromosomal anomalies appearsto be associated with living in deprived areas, althoughthis relationship is not a simple one. Chromosomalanomalies are known to be associated with increasedmaternal age and so crude rates are higher in moreaffluent areas. When rates are adjusted for age thispattern disappears. Rates of non chromosomalanomalies are higher in more deprived areas.

There are a number of areas for further study arisingfrom this initial work on congenital anomalies anddeprivation in Wales, including looking at some keyindividual anomalies. CARIS will work with the NPHS to look at this in greater detail over the coming year.

annual review | 17

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Antenatal detection in Wales


Antenatal Screening andInterventions

One of the significant moments in apregnancy for parents is the ultrasoundanomaly scan. Today this comes with theoption of photographs, the chance ofdiscovering the baby’s sex and making the experience a shared family event.

On a more serious note the 20 week scanhas become the mainstay of antenatalscreening.

The objectives for screening includereassurance that the baby is normal andidentification of• non viable abnormalities

• abnormalities associated with highmorbidity and long term handicap

• fetal conditions with the potential for intrauterine therapy

• fetal conditions which will requirepostnatal investigation/ treatment

and

• parental preparation.

CARIS aims to collect data to informclinicians and Antenatal Screening Wales on the effectiveness of antenatal screeningthroughout the delivery units in Wales.Since CARIS started, screening techniqueshave changed, improved and become moreuniformly available to Welsh mothers.

An antenatal anomaly is normally reportedto CARIS by the ultrasonographer at thetime of detection. This has enabled us toestimate the detection rate in certainconditions. Changes to the RadIS reportingmodule will streamline reporting whenavailable throughout Wales. A report to theregister will be generated at everyultrasound scan where an anomaly isdetected. Most units should be equippedfor this by 2009.

Antenatal Screening Wales producesliterature to help women navigate theexperience of ultrasound and screening. An information leaflet is produced byAntenatal Screening Wales and, in theabsence of more robust or Wales specificdata, the leaflet quotes the RCOGindicative detection rates. For this reportwe have compared the quoted antenatal detection rates with the actual reports that CARIS receives.

Neural tube defectsThese are the most common central nervoussystem abnormalities likely to be diagnosedby an ultrasonographer. The defects include spina bifida, anencephaly andencephalocoele and relate to a problem with development of the spine leaving thebrain or spinal cord exposed. In Wales theprevalence is 1.7/1000 total births.

The Antenatal Screening Wales informationleaflet suggests a 90% chance of spina bifidabeing seen at the 18-20 week anomaly scanand a 99% chance for anencephaly.

Risk Factors for Neural Tube Defects

Geography - high in Walescompared to WesternEurope

Family history - previous affected childor mother, maternaldiabetes

Diet - folate poor nutrition ormetabolism

Teratogenic drugs - antiepileptic drugs,methotrexate, retinoicacid

Chromosomal - particularly trisomy 13anomalies and trisomy 18

annual review | 19

As ultrasound expertise and technology have improved, the detection potential hasincreased for antenatal screening. This hasmeant that the dependence on maternalserum alphafetoprotein has greatlydiminished. It also has reduced the need for confirmatory amniocentesis to estimateacetylcholinesterase and alphafetoprotein in the liqour.

Figure 19: Ultrasound showing anencephaly.

CARIS data shows that the detection ofanencephaly before 24 weeks gestation over the 10 year period 1998-2007 was97.2%. Increasingly anencephaly is beingdetected on the 10-14 week dating scan(Figures 19 & 20). In 2007 early detection on the dating scan accounted for 76.9% of cases.

Figure 20: Proportion of cases of non-chromosomal anencephaly detected at datingscan (10-14 weeks gestation).

Overall antenatal detection of spina bifida inWales before 24 weeks gestation between1998-2007 is 85.1%. This is a little below the90% figure used by Antenatal ScreeningWales. Figure 21 shows detection at variousgestational ages and the overall detection rate before 24 weeks.

Figure 21: Proportion of cases of non-chromosomal spina bifida detected at differingstages of gestation.

Key Ultrasound Pointers forNeural Tube Defects• splaying of spine ossification centres

• defect in the skin line at the lesion

• cystic meningeal sac

• loss of normal spinal curvature

• absence of the skull vault

• lemon shaped skull

• banana/boomerang shaped cerebellum

• third ventricular enlargement

• microcephaly/enlarging ventricles

0

10

20

30

40

50

60

70

80

1998 1999 2000 2001 2002 2003 2004 2005 2006 2007

Year

Per

cent

age

0

10

20

30

40

50

60

70

80

90

100

Per

cent

age

1998 1999 2000 2001 2002 2003 2004 2005 2006 2007

Year

% detected on anomaly scan (18-20 weeks)

% detected between 15-17 weeks

% detected on dating scan (10-14 weeks)

Total % detected by 24 weeks



HydrocephalyHydrocephaly is caused by the accumulationof cerebrospinal fluid within the ventricularsystem. Usually an obstruction of theaqueduct or posterior fossa is responsible. In spina bifida it can be caused by the Arnold Chiari malformation.

Ventriculomegaly is a descriptive term whichrecords increased ventricle size above 10mm and not implying any signs ofincreased pressure.

Over the last 10 years 312 cases ofhydrocephaly have been reported. Of these250 were non-chromosomal. For these,overall antenatal detection before 24 weekswas 50.4%, although detection is muchbetter in more recent years as shown inFigure 22. Detection is now reasonably closeto the Antenatal Screening Wales leaflet figure of 60% by 24 weeks gestation.

Figure 22: Antenatal detection of non-chromosomal hydrocephaly before 24 weeksgestation (1998-2007).

Major Heart ProblemsCardiac congenital anomalies are the mostcommon seen and account for significantmorbidity and mortality. Antenatal detection is challenging and is based on securing a four chamber view and assessment of theoutflow tracts. This will include the six cardiac connections.

Right side of the Heart

• inferior and superior venaecavae drain to right atrium

• right atrium connectsthrough tricuspid valve to right ventricle

• right ventricle connects to pulmonary artery

Left side of the Heart

• pulmonary veins drain into left atrium• left atrium connects through mitral valve

to left ventricle• left ventricle connects to the aorta

Babies with major heart problems are thosethat will require specialist help when born.Antenatal detection is very important inplanning delivery and sometimes immediatepostnatal care.

CARIS data shows that the detection rate ofmany heart anomalies is improving. The ASWinformation leaflet gives a 25% chance ofhaving a major heart anomaly diagnosed atthe anomaly scan. Overall detection ofhypoplastic left heart syndrome by 24 weeksgestation is 68.7% but in 2007 this was ashigh as 83.3%. Detection rates are muchlower for other conditions includingtransposition of great arteries. The 10 yearantenatal detection rate for transposition isjust 16.0% by 24 weeks gestation.

Ultrasound Plan for Hydrocephaly• inspect brain for any structural abnormality

• look for other system anomalies

• exclude infection

• offer karyotype

20

30

40

50

60

70

80

1998 1999 2000 2001 2002 2003 2004 2005 2006 2007

Year

Per

cent

age

Figure 23: Fetal heart -normal 4 chamber view

annual review | 21annual review | 21

Diaphragmatic hernia If abdominal contents are able to pass intothe thoracic cavity, lung development can becompromised. The earlier this happens themore likely it is that pulmonary hypoplasia willoccur and jeopardise survival.

The finding of a diaphragmatic hernia at anultrasound scan presents a difficult dilemma in predicting outcome.

Antenatal detection rates seem quite variablefor this condition with detection varyingacross the years from 11.1% in 2004 to83.3% in 2006 (Figure 24). The overall 10 year detection rate is 47.3%. ASW leafletgives a 60% chance of detection at theanomaly scan.

Figure 24: Time of diagnosis in antenatallydetected diaphragmatic hernia (1998-2007).

Exomphalos This is an incomplete return of the abdominalcontents to the abdominal cavity in earlypregnancy. Bowel is usually present as can be stomach, liver or spleen, held within arelatively thick membrane. It is frequentlyassociated with other abnormalities, and inover a third of cases, is associated withchromosomal disorders (Figure 25).

Figure 25: Aetiological description of cases of exomphalos (1998-2007).

The detection rate by 24 weeks gestation is77.8% over the last 10 years. Increasinglymore cases are being detected at the 10-14 week dating scan.

Figure 26: Proportion of non-chromosomalcases of exomphalos detected at dating scan(10-14 weeks) 1998-2007.

Poor prognostic signs for diaphragmatic hernia• other abnormalities, commonest being cardiac and chromosomal

• diagnosis before 24 weeks

• polyhydramnios

• hydrops fetalis

• intrauterine growth retardation

Dating scan(10-14 weeks)

2%15-17 weeks

6%

Anomaly scan(18-20 weeks)

53%

21- <24 weeks20%

24+ weeks16%

Gestationunknown

3%

Early scan < 10 weeks 0Dating scan (10-14 weeks) 115-17 weeks 4Anomaly Scan (18-20 weeks) 3421 - < 24 weeks 1324+ weeks 10Gestation unknown 2

Syndromic8%

Chromosomal37%

Multiple27%

Isolated28%

0

10

20

30

40

50

60

70

1998 1999 2000 2001 2002 2003 2004 2005 2006 2007

Year

Per

cent

age


Gastroschisis Gastroschisis has a high prevalence in Wales.It consists of a hernia of abdominal contentsthrough the abdominal wall usually to the rightof the umbilical cord insertion. Bowel floatsfreely in the amniotic fluid and this contactmay be responsible for complicationsaffecting the bowel.

As with exomphalos, antenatal detection isincreasingly occurring earlier in pregnancy.Many cases reported to CARIS are detectedat the 10-14 week dating scan. The overalldetection rate by 24 weeks gestation is86.9%. (See Figure 27 for more detailedbreakdown of when antenatally detectedcases were identified). The ASW leaflet givesa 90% chance of detection of gastroschisis or exomphalos at the anomaly scan.

Figure 27: Time of diagnosis in antenatallydetected non-chromosomal cases ofgastroschisis (1998-2007).

Figure 28: Antenatal scan showinggastroschisis.

Major renal problems Renal agenesis and multicystic kidneysaccount for the majority of serious kidney problems.

Bilateral renal agenesis is associated witholigohydramnios giving the characteristicPotter’s syndrome of low set ears, wide seteyes, micrognathia, limb contractures, talipesand pulmonary hypoplasia. Liquor volume can be normal before 17 weeks. After this,oligohydramnios can make the demonstrationof absent kidneys and bladder difficult.Changes in the shape of the adrenal glandsand absence of the renal arteries shown bycolour Doppler may be helpful.

Multicystic kidneys are easier to detect as thekidneys are enlarged and echogenic despiteassociated oligohydramnios. It may not bepossible to detect these until 24 weeksgestation. Earlier subtle increases in size maybe detectable as may early hyperechogenicity.

CARIS data shows that 83.7% of cases ofrenal agenesis and 63.9% of multicysticdysplastic kidneys are detected by 24 weeksgestation. The ASW leaflet suggests a figureof 85% for the antenatal detection of majorkidney problems.



Dating scan(10-14 weeks)

23%

15-17 weeks24%

Early scan < 10 weeks 0Dating scan (10-14 weeks) 4215-17 weeks 44Anomaly Scan (18-20 weeks) 6521 - < 24 weeks 1524+ weeks 12Gestation unknown 6

Anomaly scan(18-20 weeks)

35%

21- <24 weeks8%

24+ weeks7%

Gestationunknown

3%

annual review | 23

Missing bones or very short armsor legs At the 18 to 20 week scan a survey is madeof bony structures and measurements taken.These include the biparietal diameter, headcircumference and femur length. Morphologyof the bones including cranial vault and ribs is assessed at the same time.

Amniotic bands are thoughtto be responsible for abouthalf of limb deficiencies andamputations. In these thereis usually a transverse defectonly. Most reductions of theupper limbs are isolatedevents, those involving thelower limbs are often part ofmore complex problems.Although the ASW leafletsuggests a 90% chance ofthese being diagnosed at theanomaly scan, CARIS datashows that this is a veryheterogenous group.

Diagnosis takes place at various times so it isdifficult to give an overall detection rate.

Heart and Bowel Problems connectedwith Downs Syndrome

Soft markersUltrasound soft markers for chromosomalabnormalities remain a controversial area.Scans of many normal fetuses maydemonstrate soft markers which are specificappearances on the scan without anunderlying structural anomaly. Drawing attention to this may cause parental anxiety and result in unnecessaryamniocenteses and potential fetal loss.

At present there is not enough evidence tosupport karyotyping fetuses with soft markersin a low risk population.

Specific anomaliesDuodenal atresia and atrioventricular septaldefect are common abnormalities with Down syndrome. Increased nuchal thickeningcan be a useful sign to suggest a karyotypeshould be offered to the mother.

Of the 709 cases of Down syndrome reportedto CARIS, 87 (12%) had an atrioventricularseptal defect and 5 (0.7%) were reported tohave duodenal atresia. The ASW leafletsuggests a 40% chance of picking up heartand bowel problems connected withDown syndrome.

annual review | 23

Figure 29: Xray showingbilateral agenesis of radius and ulna.


Health Service Provision The importance of collecting accuratecongenital anomaly data can affect theway the health service works for thepopulation of Wales.

Describing patterns of servicesCARIS can increasingly give an insight into the ways that different services andinterventions interact to assist with patient care.

The NHS in Wales has used CARIS datarelating to cardiac anomalies and cleft lipand palate to plan services.

We have a close relationship withAntenatal Screening Wales and help withdetails of antenatal detection andoutcomes. For example, Figure 30 showsthe different pathways taken foramniocentesis to be performed for casesof Down syndrome.

Figure 30: Reason for amniocentesis in cases of trisomy 21 (1998-2007).

One of the advantages of good antenatalscreening and detection is the ability toplan delivery in a suitable unit withappropriate paediatric resources.

Diaphragmatic herniae and severe cardiacanomalies are examples of conditions thatbenefit from delivery in a tertiary centre andCARIS can record the appropriateness ofplace of delivery. Figure 31 illustrates howbabies, who are live born followingantenatal detection of diaphragmatic herniain Wales, are over eight times more likely tobe delivered in a tertiary centre than thosenot detected before birth.

Figure 31: Diaphragmatic hernia - antenataldetection and delivery for live born babies(1998-2007).


Tertiary Non-tertiarydelivery delivery

Antenatally detected 41 3

Not antenatally detected 5 35

Total 46 381%

15%

5%

13%

1%2%

0%47%

6%

9%1%

Abnormal dating scan (10-14 weeks) 47

Abnormal scans (15-17 weeks) 14

Abnormal anomaly scan (18-20 weeks) 40

Abnormal scan (21-23 weeks) 2

Abnormal scan (24 weeks+) 7

Abnormal scan gestation age not known 1

High risk Serum screen 145

Maternal Age (35-39) 18

Maternal Age (40+) 27

Family history 4

Unknown 3

annual review | 25

Information for parents Expectant mothers can find out about CARISthrough Antenatal Screening Wales or fromwall posters distributed through mostantenatal clinics.

If an anomaly is detected antenatally, theregister can help by providing outcome datato inform and help with decision making. For example, Figure 32 illustrates recordedsurvival outcomes for hypoplastic left heart.

Figure 32: Outcomes in non-chromosomalhypoplastic left heart syndrome (1998-2006).

Health professionals who are aware of CARISmay find that this helps the counsellingprocess when faced with a woman who hasdelivered a baby with a congenital anomaly. It can be reassuring to parents that there is a system for recording, analysing and making sense of what has happened.

To help with this we have developed a parentinformation leaflet to explain the register in detail.

annual review | 25

Terminated - 40 (46%)

Stillbirth - 3 (3%)

Livebirths 44 (51%)

Survival to 1 year - 23(52% of livebirths)

Died within 1 year - 21(48% of livebirths)

CARIS works very closely with the screeningservices in Wales. We are delighted to heardetails of the services offered.

Antenatal Screening Wales –

Rosemary JohnsonDirector of AntenatalScreening Wales

When and why were you set up?

In 2001 there was no national system formanaging and monitoring antenatal screeningin Wales and variable access to somescreening tests.

Antenatal Screening Wales was set up toensure pregnant women were offered auniform screening service with carefulmaintenance of standards.

We have worked closely with NHS Trusts and key stakeholders, including CARIS,establishing a framework for the antenatalscreening programme in Wales.

How do you compare with England?The Department of Health has established adifferent structure in England. This includescommissioning Programme Centres to leadspecific antenatal screening programmes, for example the Fetal Anomaly and Down’ssyndrome Screening Programme Centre.

What would you reckon is thegreatest achievement of AntenatalScreening Wales?I think this is the close collaboration we havedeveloped with different specialities andstakeholders across Wales.

This lively debate has resulted in consensusabout best practice and evidence basedantenatal screening services for women.

What about the most difficultobstacle – what was that?This has been prioritising issues and decidingwhich ones we take forward in any given year.Antenatal screening is complex with multiplescreening tests and many ethical issues toaddress within our current budget. The lack of an all-Wales Information Management &Technology (IM&T) strategy for maternityservices continues to make servicedevelopment, planning and monitoringparticularly difficult.

(Margery Morgan) I agree. With no uniformmaternity database in Wales, comparison ofpregnancies with normal babies and thosewith congenital anomalies is impossible.

How are things going to change in the next 10 years?I would expect to see major improvements in the Down’s syndrome screeningprogramme leading to a higher detection rate with a lower false positive rate.

The RadIS II obstetric reporting module,currently being introduced to units aroundWales, should provide us with audit data toanalyse the performance of ultrasound anddetection of structural fetal anomalies.

Above all we hope to have an all-Wales IM&T strategy for maternity services whichincludes antenatal screening to make servicedevelopment, planning and monitoring easierand in line with the requirements of otherscreening programmes.

Screening services in Wales


Where does CARIS fit in?CARIS is vital to the work of ASW because it provides high quality information aboutpregnancy outcomes and the performance of many aspects of the antenatal screeningprogramme. Without CARIS we would beunable to assess the effectiveness of anumber of the screening tests.

Thank you Rosemary

Newborn Screening Wales

Don BradleyDirector of NeonatalScreening

When and why was Newbornscreening Wales set up?

Phenylketonuria

Newborn screening was originally introducedto detect phenylketonuria (PKU), an inbornerror of metabolism of the amino acidphenylalanine, first described in 1934.

Greatly elevated levels of phenylalanine arepresent in the blood in the first week of lifeand this leads to profound learning difficultiesif untreated. Work in the 1950s led to the ideathat if the disease could be detected pre-symptomatically and a diet low inphenylalanine introduced, then normaldevelopment was possible. This led theeponymous Robert Guthrie to invent histechnique of collecting whole blood fromnewborns onto filter paper from a heel-prickand measuring the phenylalanine by hisbacterial inhibition assay. In the 21st centuryvirtually all PKU screening is undertaken bytandem mass spectrometry. The birthprevalence of PKU in Wales is approx.1:10,000.

Screening started in Wales during 1970 andcurrently we screen over 34,000 newbornseach year.

Congenital hypothyroidism

With the introduction of radio-immuno assaysin the 1970s an assay for thyroid stimulatinghormone (TSH) became available leading tothe introduction of screening for congenitalhypothyroidism (CHT) in 1982. CHT isgenerally due to either agenesis or ectopicdevelopment of the thyroid gland leading toelevated TSH levels, reduced levels ofthyroxine and consequent learning difficulties.Identification in the first week of life followedby life-long treatment with thyroxine leads tonormal development. The birth prevalence ofCHT in Wales is 1:2,600.

annual review | 27

Screening questions and answers


Cystic Fibrosis

It has been possible to screen newborns forcystic fibrosis since the late 1970s bymeasuring immuno-reactive trypsin (IRT) in a heel-prick blood spot. The test had poorspecificity leading to large numbers of falsepositive tests which then required a sweattest to confirm or refute the screening test.

In 1989 the gene for cystic fibrosis wasisolated and the most common gene defect(▲▲F508) identified. At the same time evidencesuggested that outcome was better in thosediagnosed early. False positive tests are rarethese days with limited molecular analysis asa second tier check. Screening started inWales in December 1996. The birthprevalence of CF in Wales is approximately 1:2,500.

Duchenne Muscular Dystrophy

Duchenne muscular dystrophy (DMD) is anuntreatable, lethal, X-linked disease affectingabout 1:4,500 males with a third of casesarising from new mutations. Boys are normalat birth, with clinical symptoms of muscleweakness becoming evident between 3 and 4 years. Muscle deterioration continues andthose affected rarely live beyond 20-25 years.

The traditional diagnostic process is oftenprolonged and further affected siblings maybe born before the first has been diagnosed.Again, newborn screening has been possiblesince the 1970s by measuring creatine kinase(a marker of muscle disease) in the heel-prickblood spot, but it was the isolation of thedystrophin gene in the 1980s and thesubsequent ability to recognise gene deletionsin affected individuals which led us toconsider newborn screening for DMD. This was clearly not on the usual grounds ofenabling early medical intervention but ratherto avoid the distressing diagnostic delay. It also enabled families to plan for the future in practical ways including reproductivechoice in further pregnancies. Screening hasbeen available since the late 90’s.

How do you compare with England?Currently there are 14 laboratories in Englandoffering newborn screening for PKU and CHT.

Those labs covering populations with a highprevalence of sickle cell disorder have offeredscreening since the 1990s. The diseaseprimarily affects those from sub-SaharanAfrica, the Caribbean, the Mediterranean andthe Middle East.

There are plans (2009) to screen for mediumchain acyl-CoA dehydrogenase deficiency, the most common disorder of fatty acidoxidation. Affected individuals are unable tocreate energy from fat during periods offasting, intercurrent illness with fever, orsurgery. The birth prevalence of MCADD is about 1:12,000.

At present screening for these two disordersis not available in Wales but discussions areunderway with a view to introducing it.

CARIS data on Cystic Fibrosis in Wales• 125 infants were born between 1998-2006.

• 5 terminated pregnancies.

• Prevalence rate of 1:2200

• 14 with echogenic bowel detected antenatally.

• 23 born with meconium ileus - 6 with antenatal

echogenic bowel.

• 2 with chromosomal anomalies

• 6 with gut anomalies

What would you say the screeningprogramme has achieved?The Wales programme has achieved a greatdeal with minimal resources.

We were:

- the first laboratory to design a computerisedrecording and reporting system in the 1970s

- the first to design and implement two-tierCF screening.

We also introduced screening for DuchenneMuscular Dystrophy, a disease whichchallenges conventional screening principles.This involved gaining parental informedconsent, again a first in newborn screening.We have published widely on thepsychosocial and other aspects of newborn screening.

What would you say were obstaclesto the programme?Information technology is a major issuebecause only through an integrated systemcan we ensure that every newborn is not onlytested, but tested during the first week of life.The NHS number which is allocated shortlyafter birth should become the main identifierfor all newborns but this is not yet the case in Wales.

Also there is a lack of governance of theprogramme which makes some issues difficult to address.

What about missed cases and false positives?In Wales we have not seen either falsenegatives or false positives for PKU; we wouldexpect to miss about 7% of cases of CF and10% of cases of DMD but with very few falsepositives. CHT Screening is complicated sincemild transient elevations of TSH are commonin neonates and the disorder may developlater in life.

How are things going to develop in the next 10 years?Newborn screening in the UK is ratherconservative and probably rightly so. It is notuncommon for more than 20 disorders to beincluded in the screening panel in manycountries. Many of these are rare, where there is little known of their natural history and where treatment may be problematic.There will be modest, hopefully evidence-based, additions in the next 10 years.

Where does CARIS fit in?All affected individuals identified by screeningare reported to CARIS. This enables thesedisorders to be placed into the context of allcongenital anomalies in Wales.

Thank you Don

annual review | 29

Screening services in Wales


Newborn Hearing ScreeningWales

Sally MinchomDirector of NeonatalHearing Screening Wales

What is the story about newbornhearing screening in Wales – whenand why were you set up?

This is a national programme that screensbabies’ hearing shortly after birth. It was fullyimplemented in Wales in October 2004.

The effect on the child and family ofundiagnosed deafness can be significant. It can cause impaired language development,communication, family functioning, literacy,social and emotional well being and affectemployment prospects. Early identificationand intervention (before 6 months) have beenfound to reduce these deficits.

Distraction tests done by health visitors beforethis were not effective.

What type of hearing loss do yourecord?We record permanent bilateral hearing lossgreater then 40 dBHL. We also keepinformation on mild hearing loss, unilateralhearing loss and auditory neuropathyspectrum.

How do you compare with England?We work closely and compare very well withEngland doing slightly better in terms ofscreens offered and coverage.

What would you say the screeningprogramme has achieved?The screening programme performs to a high standard.

- 99.9% of eligible babies are offeredscreening and 99.3% of babies are tested

- 79.1% of babies are tested within 7 days

- 100% of high risk babies and 97% of wellbabies complete the screen in 4 weeks

- 1.3% babies screened are referred forassessment

- Of those assessed, about half (0.6% of allbabies screened) have normal hearing

- 86.5% of babies referred have beenassessed by 3 months of age

Since the introduction of universal newbornhearing screening, 1.3 per 1000 babies havebeen identified as having permanentsignificant bilateral hearing loss (defined asgreater than 40 dBnHL). The mean age ofhearing aid fitting was 30 weeks (median 18 weeks). This figure includes babies wherethe original decision not to fit hearing aids wasaltered after further information was gainedabout the hearing loss or parents reviewedtheir initial decision. 62% had hearing aidsfitted within 4 weeks of confirmation ofhearing loss.

The bottom line is that the programme hasidentified more than the predicted number ofbabies which had been thought to be 1.1 per1000 babies from previously collected UKfigures. Hearing aids and support serviceshave been introduced to families at asignificantly earlier time.

The programme has also succeeded byworking closely with audiologists andpaediatricians and as a result local trusts haveimproved services for children. Networkingteams have been established across Waleswith audit and training.

annual review | 31

What would you say were obstaclesto the programme?The information system! We use the ChildHealth system of which there are 12 in Waleswith potential inaccuracies with data transfer.

Agenda for change was a disappointment tomany of our staff especially the screenerswho received a lower banding compared toscreeners in the rest of the UK.

We would appreciate it if midwives coulddistribute leaflets more effectively to givemothers time to think about screening before delivery.

What about missed cases and falsenegatives?We collect information about all childrendiagnosed with hearing loss in Wales.Included in these cases will be children whohave not been diagnosed by the screeningprogramme. Some of these will be truemissed cases either missed by screening with a false screen pass or a very smallnumber who do not receive a screening test.Some babies identified as needing anassessment do not attend.

Some children have progressive or acquiredhearing loss which makes interpreting thedata difficult. We rely on children not pickedup by the programme being identified byhealth visitors and other professionals. The programme has only been running for 5 years and so we are only just beginning tocollect this data.

What associated congenitalanomalies do you see?Sensorineural hearing loss can occur inisolation or as part of a syndrome. Hearingloss can run in the family or occur with nofamily history. The commonest associatedabnormalities are of the head and neck.Babies needing Special Care are high risk

and follow a different screening pathway from well babies.

How are things going to develop in the next 10 years?In the next 10 years, I would like to see amore combined approach to antenatal andneonatal screening programmes. Parentsneed to have timely information to makechoices about screening tests.

I look forward to the development ofassessment of neonates for hearing losswhich so far has proved to be exacting andchallenging.

Being able to provide more information aboutthe nature of hearing loss shortly after birthwill allow better hearing aid fitting and whereappropriate earlier cochlear implants. This should help communication developmentin young children.

Where does CARIS fit in?Paediatricians should notify CARIS ofsignificant congenital hearing loss and soCARIS should have information about all thechildren held on the NBHSW hearing impaireddatabase. In the longer term we would hopeto work with CARIS to analyse our data onhearing loss and additional congenitalanomalies.

More information about Newborn HearingScreening Wales can be obtained on our websitewww.screeningservices.org/nbhsw

Thank you Sally but I fear that paediatriciansdo not let us know of all cases.

CARIS data is thought to be incomplete. 215 cases have been reported in the 10 yearperiod (1998-2007) giving a prevalence of 6.6 per 10,000 live births.


Appendix A: How CARIS operatesWe collect data on any baby or fetus, forwhom pregnancy ended after 1st January1998, where the mother is normally resident in Wales at the end of pregnancy.

CARIS uses a multiple source reportingsystem and, at present, over 100 individualsor agencies regularly send us information.

Data from clinical and laboratory sources arereported via warning cards, reporting formsand data exchanges. CARIS co-ordinators in each trust are responsible for much of the clinical reporting (details available fromour website).

In the CARIS office, data are collated;information is coded and quality carefullychecked. The data are then available forfeedback to clinicians – paediatricians,ultrasonographers, midwives, etc. We alsosupply information to the National Assemblyfor Wales, EUROCAT, International ClearingHouse for Birth Defects and the Office forNational Statistics (NCAS) for surveillance.

We cannot overemphasise the importance wegive to data confidentiality. We operate a strictsecurity and confidentiality policy and havegained support under Section 60 of theHealth and Social Care Act 2001. This isrenewed annually. This means that the registercan continue collecting and analysing data.

CARIS has set up an Expert Advisory Groupto advise on future developments and monitorprogress of the register.

Over 37,000 recorded pregnancies occur inWales each year. Of these, about threequarters are registered as live or still births,the rest ending in termination or spontaneousloss of the fetus before the 24th week ofpregnancy. About 3% of births take place athome. Wales has 13 consultant obstetric units

and 13 midwifery led units. The majority ofbirths take place in these units. However, asignificant number of births to Welshmothers occur in English hospitals. Goodlinks with congenital anomaly registers thatborder Wales (Mersey, West Midlands andthe South West of England) remainimportant. Clinical reporting is invaluable inidentifying cases to CARIS, particularly thosebabies who:

• die but do not have a post mortem

• survive and have anomalies not requiring

immediate specialist help.

Clinical reporting also gives details such asexpected date of delivery that can be difficultto obtain from other sources.

Diagnostic services, particularly ultra soundand pathology, can alert us to a case or givevaluable further information. Regionalspecialist services, including cytogenetics, can help by providing more details of theanomalies involved. We also link to otherdatabases, such as PROTOS (Cardiff), RadIS(Radiology information system), the All WalesPerinatal Survey and the Standard ChildHealth Computer System.

annual review | 33

Central Nervous SystemAnencephaly 220 6.8 6 0.2 3%

Encephalocele 69 2.1 18 0.6 26%Spina Bifida 256 7.9 48 1.5 19%

Hydrocephaly 310 9.6 143 4.4 46%Cataracts 114 3.5 114 3.5 100%

Sensorineural deafness 215 6.6 215 6.7 100%

PulmonaryCongenital cystic adenomatoid

malformation of lung 41 1.3 34 1.1 83%

CardiovascularHypoplastic left heart syndrome 112 3.5 51 1.6 46%

Transposition of great vessels 130 4.0 104 3.2 80%Ventricular septal defects 1,640 50.7 1,490 46.3 91%

GastrointestinalCleft lip with / without cleft palate 360 11.1 286 8.9 79%

Cleft palate 317 9.8 252 7.8 79%

GenitourinaryHypospadias 840 26.0 835 25.9 99%

Multicystic kidney 196 6.1 137 4.3 70%Bilateral renal agenesis 51 1.6 0 0.0 0%

Musculoskeletal / limbsGastroschisis 195 6.0 173 5.4 89%

Diaphragmatic hernia 126 3.9 86 2.7 68%Craniosynostosis 198 6.1 179 5.6 90%

Limb reduction defects 335 10.4 203 6.3 61%Dislocation / dyplasia of hip 703 21.7 698 21.7 99%

Endocrine / metabolicCystic fibrosis 152 4.7 146 4.5 96%

Congenital hypothyroidism 179 5.5 179 5.6 100%

ChromosomalTrisomy 21 (Down syndrome) 709 21.9 326 10.1 46%

Trisomy 18 (Edwards syndrome) 193 6.0 41 1.3 21%45 X, (Turner syndrome) 138 4.3 40 1.2 29%

Appendix B: ‘Top 25’ conditions:prevalence rate 1998-2007

ANOMALY ALL CASES LIVE BORN CASESTotal Number of Rate per % cases

number of Rate per 10,000 live born 10,000 live live borncases total births cases births

10 year live birth prevalenceCondition Rate per 10,000 Birth

Number live births ratio

Autosomal dominant conditionsNeurofibromatosis 68 2.11 1:4735Hereditary spherocytosis 17 0.53 1:18940Tuberous sclerosis 14 0.43 1:23000Achondroplasia 12 0.37 1:26830Hereditary motor and sensory 9 0.28 1:35770neuropathy (Charcot-Marie-Tooth)Myotonic dystrophy 6 0.19 1:53660Multiple congenital exostoses 5 0.16 1:64390

Autosomal recessive conditionsCystic fibrosis 146 4.5 1:2205Phenylketonuria 33 1.02 1:9755Spinal muscular atrophy 17 0.53 1:18940

Microdeletion conditions22q deletion / Di George syndrome 46 1.43 1:7000William's syndrome 14 0.43 1:23000Prader Willi Syndrome 13 0.40 1:24765Angelman's syndrome 11 0.34 1:29270Smith-Magenis syndrome 3 0.09 1:107320

SyndromesNoonan syndrome 22 0.68 1:14635Marfan's syndrome 20 0.62 1:16100Beckwith-Wiedemann Syndrome 19 0.59 1:16945Goldenhar syndrome 14 0.43 1:23000Sotos syndrome 7 0.22 1:45990Saethre-Chotzen syndrome - 6 0.19 1:53660(Acrocephalosyndactyly type III)Smith-Lemli-Opitz syndrome 6 0.19 1:53660CHARGE 5 0.16 1:64390Cornelia de Lange syndrome 5 0.16 1:64390Kabuki make-up syndrome 4 0.12 1:80490Moebius syndrome 4 0.12 1:80490Pfeiffer syndrome 4 0.12 1:80490Aperts syndrome 3 0.09 1:107320Klippel-Trenaunay-Weber syndrome 3 0.09 1:107320Zellweger Syndrome 3 0.09 1:107320

Appendix C: CARIS data onselected rare conditions


Documents

Congenital Anomaly Register & Information Service for Wales Ann rep (Eng... · 2015-10-27 · 2 | annual review CONGENITAL ANOMALY REGISTER & INFORMATION SERVICE Foreword 3 CARIS