Epidemiology of vitamin D deficiency Epidemiology of vitamin D deficiency in children presenting to a paediatric in children presenting to a paediatric outpatient service in the UKoutpatient service in the UK

J M Reed, J H Davies, L Blake, A Jackson, J M Reed, J H Davies, L Blake, A Jackson, N M P Clarke N M P Clarke

Southampton General Hospital Southampton General Hospital & University of Southampton& University of Southampton

BackgroundBackground

Vitamin D3 (cholecalciferol) is obtained Vitamin D3 (cholecalciferol) is obtained from 2 sources: from 2 sources: Sunlight exposure (UV-B rays)Sunlight exposure (UV-B rays)

Dietary intake: oily fish products, fortified Dietary intake: oily fish products, fortified products and supplements.products and supplements.

Formation of cholecalciferolFormation of cholecalciferol

7-dehydrocholesterol

BackgroundBackground

DefinitionsDefinitions

Davies et al, Arch Dis Child 2010; Cheetham et al, BMJ 2010; Misra et al Pediatrics 2008

Prevalence of vitamin D deficiency in Prevalence of vitamin D deficiency in developed countries, adults vs. childrendeveloped countries, adults vs. children

Hypponen et al, Hypponen et al, Am J Clin Nutr, 2007Am J Clin Nutr, 2007 n=7347, age 45 y, UK, all white, winter/ spring 25-OHD measurementn=7347, age 45 y, UK, all white, winter/ spring 25-OHD measurement 87.1% < 75 nmol/l87.1% < 75 nmol/l 46.6% < 40 nmol/l46.6% < 40 nmol/l 15.5% < 25 nmol/l15.5% < 25 nmol/l

Ford et al, Ford et al, Ann Clin Biochem, 2006Ann Clin Biochem, 2006 n=830, UK adults, multicultural inner city, Sept 25-OHD measurementn=830, UK adults, multicultural inner city, Sept 25-OHD measurement < 25 nmol/l:< 25 nmol/l: 1 in 8 White1 in 8 White

1 in 4 Black Afro-Caribbean1 in 4 Black Afro-Caribbean1 in 3 Asians1 in 3 Asians

Kumar et al, Kumar et al, Pediatrics, 2009Pediatrics, 2009 n=6275, USA, age 1-21 y, NHANES 2001-2004, 25-OHD measurementn=6275, USA, age 1-21 y, NHANES 2001-2004, 25-OHD measurement 61%, 37.5-72.5 nmol/l61%, 37.5-72.5 nmol/l 9%, < 37.5 nmol/l9%, < 37.5 nmol/l association with cardiovascular risk factorsassociation with cardiovascular risk factors

what is the prevalence of vitamin D deficiency in UK children? what is the prevalence of vitamin D deficiency in UK children?

• 16 infants (6 Asian, 10 Black) from UK• all breast fed• 6 cardiac arrest• 3 died• 8 ventilated• 2 required by-pass• 12 required IV support• 2 referred for cardiac transplant

Heart 2006

Mode of presentation of symptomatic Mode of presentation of symptomatic vitamin D deficiency in the UKvitamin D deficiency in the UK

Recent trends & clinical features of vitamin D deficiency Recent trends & clinical features of vitamin D deficiency presenting to a children’s hospital in Glasgowpresenting to a children’s hospital in Glasgow

Ahmed et al, Arch Dis Child, 2010

MethodsMethods

Prospective study to investigate the Prospective study to investigate the prevalence of deficiency in our patient prevalence of deficiency in our patient populationpopulation

Vitamin D level in known bone pathologiesVitamin D level in known bone pathologies- or- or

Requested as part of investigative work-up for Requested as part of investigative work-up for unexplained bone painunexplained bone pain

Stages of Tibia VaraStages of Tibia Vara

1 2 3 4 5 6

Changing incidence of slipped Changing incidence of slipped capital femoral epiphysis: capital femoral epiphysis:

A relationship with obesityA relationship with obesity

JBJS Br. 2008; 90: 92-4

31.1.10 2.6.10

Vitamin D deficiency in children presenting to the Vitamin D deficiency in children presenting to the paediatric orthopaedic clinic, Southampton (1)paediatric orthopaedic clinic, Southampton (1)

25-OHD measured in those with bone pain or deformity25-OHD measured in those with bone pain or deformity 187 children from 2008 – 2010187 children from 2008 – 2010 75 deficient (60 insufficiency, 15 severe deficiency)75 deficient (60 insufficiency, 15 severe deficiency)

Vitamin D deficiency in children presenting to the Vitamin D deficiency in children presenting to the paediatric orthopaedic clinic, Southampton (2)paediatric orthopaedic clinic, Southampton (2)

Further analysisFurther analysis

No specific diagnosis was associated No specific diagnosis was associated with a high or low vitamin D levelwith a high or low vitamin D level

There was a lower vitamin D level found There was a lower vitamin D level found in children with unexplained joint pain in children with unexplained joint pain (mean 22.5) compared to those with (mean 22.5) compared to those with other diagnoses (mean 30.7). This was other diagnoses (mean 30.7). This was significant p<0.05. significant p<0.05.

PreventionPrevention

Infant vitamin D RNIsInfant vitamin D RNIs 8.5 ug/d up to 6 months age8.5 ug/d up to 6 months age 7 ug/d up to age 3 years7 ug/d up to age 3 years

Chief Medical Officer, 20/1/2011, DOH websiteChief Medical Officer, 20/1/2011, DOH website

““children from the age of six months to five children from the age of six months to five years old should be given a daily 7 micrograms years old should be given a daily 7 micrograms vitamin D supplementvitamin D supplement””

Prevention: Healthy StartPrevention: Healthy Start

7.5 ug vitamin D37.5 ug vitamin D3

Free for some from age 6 monthsFree for some from age 6 months can be given from age 1 month on can be given from age 1 month on

doctor’s advicedoctor’s advice

Also contain vitamin A and vitamin CAlso contain vitamin A and vitamin C

Can be bought £1.78/bottleCan be bought £1.78/bottle

Healthy start uptake South East 2010Healthy start uptake South East 2010

SignificanceSignificance

Sunlight exposureSunlight exposure

15 – 20 minutes uninterrupted sunlight 15 – 20 minutes uninterrupted sunlight 3 times per week3 times per week

Vitamin D supplementsVitamin D supplements

Vitamin D status sought prior to Vitamin D status sought prior to commencing ‘observation or commencing ‘observation or orthopaedic surgical intervention’orthopaedic surgical intervention’

FracturesFracturesin 348 childrenin 348 children

Hand7.5%

Femur4.9%

Tibia/fibula7.8%

Ankle9.8%

Other1.7%

Humerus13.5%

Radius/ulna54.9%

Fat mass substantially inhibits Fat mass substantially inhibits bone accrual in children with bone accrual in children with prior fractureprior fracture

JBMR 2009

SummarySummary

Majority of active vitamin D from sunlightMajority of active vitamin D from sunlight

Increase in cases of symptomatic vitamin Increase in cases of symptomatic vitamin D deficiency (not exclusive to D deficiency (not exclusive to poverty/ethnic minorities)poverty/ethnic minorities)

Need for raised awareness and improved Need for raised awareness and improved public health measurespublic health measures