Necrotising Enterocolitis: Population approaches

Cheryl Battersby

Clinical Research Fellow

Neonatal Data Analysis Unit

Necrotising Enterocolitis

Infant mortality in UK:

Overall ↓

NEC associated ↑ (Rees et al 2008)

Affects up to 10% of low birth weight babies,

30-50% mortality (Lin and Stoll 2006)

Long-term complications (Stoll et al 2004)

Limited preventive and treatment strategies

Limited knowledge of risk factors beyond low

gestational age and birth weight

Enteral feeding: A common dilemma

First step: A population approach

To provide:

A case-definition used consistently

Sample sizes needed for future studies

Current feeding practices

Baseline incidence and systematic surveillance

NEC Surveillance: Practical challenges

Observational studies: A novel approach

The Challenges

Low incidence and small sample sizes

What is needed Collaboration

 

 

Variations in use of case-definitions

Retrospectively collected data

Paucity of population-based data

Prospectively collected routine data

 

 

Population-based incidence and systematic surveillance

 

 

An evidence-based case-definition

 

UK Neonatal Collaborative NEC STUDY

NIHR funded

Medicines for Neonates Programme

CRN portfolio adopted study

140 (86%) neonatal units: 41 level 3, 61 level 2, 38 level 1

Aims

1) To determine the population incidence of NEC in England

2) To establish an objective case-definition for NEC

3) To identify enteral-feed related factors that precede onset of NEC in order to inform the design of future interventional randomised controlled trials

Method

Analyse data collected from all babies admitted to participating neonatal units over an 18 month period

November 2011- May 2013

Dependent on the quality of data

Interim analyses on data completeness will be performed and fed back to units

Data Analysis

AIM 1: To determine the population incidence of NEC in England

Report by network using established case-definition

AIM 2: To establish an objective case-definition for NEC

Which best predicts the "gold-standard" confirmatory evidence of NEC:

“NEC on histology of resected bowel

OR visual inspection at laparotomy

OR visual inspection at post mortem examination”

Abdominal x-ray performed ad-hoc form

AIM 3: Enteral-feed related antecedents of NEC

Hypothesis: “There is an association between enteral-feed related factors and NEC”

Method: Comparing the outcome (NEC or no NEC) between groups of patients with different enteral-feed exposures

Statistical analysis: A selection of statistical methods to adjust for confounding factors

Enteral-feed related exposures

Days (from birth) to first feed

Type of first feed (Maternal Expressed Breast Milk, Human Donor Milk, Formula)

Days to reach 120ml/kg/day

Summary measure of type of feed up to development of NEC: 1) Exclusive maternal breast milk 2) Maternal breast milk with breast milk fortifier 3) Exclusive human donor milk4) Human donor milk with breast milk fortifier 5) Exclusive formula 6) Mixed human (maternal or donor) milk 7) Mixed human (maternal or donor) milk and formula8) Nil by mouth

  

Daily feeding data: Time of first feed , Type, Volume

Summary

Population-based data

Integrating clinical and research processes

UKNC-NEC study – a stepping stone for

future collaborative studies

Acknowledgements- THANK YOU

Supervisors: Professors Neena Modi and Kate Costeloe

UKNC–NEC Study Group: All neonatal units contributing data

NDAU Team

NDAU Steering Board

Jane Abbott (BLISS) Jacquie Kemp

Prof. Peter Brocklehurst Prof. Azeem Majeed

Prof. Kate Costeloe Prof. Neena Modi

Prof. Liz Draper Prof. Andrew Wilkinson