Born in Bradford

2. Born In Bradford
Neil Small
Professor of Health Research
School of Health Studies
University of Bradford
25 Trinity Road,
Bradford, BD5 OBB
Tel: 01274 236456 Fax: 01274 236458
Email: N.A.Small@bradford.ac.uk
www.bradford.ac.uk/acad/health/research/pcg

3. .. What a cohort study is and
why we are conducting one
.. Why Bradford is a good
place to do such a study
.. Study objectives
.. What data we will collect
and when
Study Benefits / Study
Challenges

4. Cohort studies: background
• You are not pre-selecting a group to study
• You can visit the same people over time.
• You can consider the whole context of a life -
how far is it ethnicity, deprivation,
genetics or behaviour that shape
a persons health profile
If you do it in one place you can link
findings with service provision

5. Existing cohort studies
• There are a wide range internationally
• UK studies include – 1946 cohort (one weeks
births) – sample of 5362 followed up at intervals
– now 21 times
• West of Scotland – 3 cohorts recruited in 1987
when aged 15, 35 and 55 – to be followed for 20
years
Millennium cohort – 19000 babies born in 2000
• ALSPAC – Avon (Bristol) 14000 children born in
1991/2

7. Why Bradford?
• Diverse population
• Stable community
• One maternity unit
• Integrated health services
• Connected IT
• Enthusiasm
• Development of research infrastructure

8. Bradford Population
• Bradford has a population of around half a million
• 22% of population are less than 15 compared to 18% in
England and Wales
• Has a significant Asian population, mainly living in inner
city areas

9. 85 plus
80 to 84
75 to 79
70 to 74
65 to 69
60 to 64
55 to 59
50 to 54
45 to 49
40 to 44
35 to 39
30 to 34
25 to 29
20 to 24
15 to 19
10 to 14
5 to 9
0 to 4
10% 8% 6% 4% 2% 0% 2% 4% 6% 8% 10%
Male Female England & Wales

10. 10
9
8
7
6
Rate per 1000 live births
5
4
3
2
1
0
1993-1995 1994-1996 1995-1997 1996-1998 1997-1999 1998-2000 1999-2001 2000-2002 2001-2003
Bradford England & Wales
Infant Mortality Rate, Bradford and England and Wales

11. 14
12 Most deprived
10
2nd most deprived
Rate per 1000 live births
8
3rd most deprived
6
2nd least deprived
4
Least deprived
2
0
1993-1997 1994-1998 1995-1999 1996-2000 1997-2001 1998-2002 1999-2003
Infant Mortality by Deprivation Quintile within Bradford
1993-97 to 1999-03

13. Comparative Infant Mortality Rates for Areas with Similar
Populations to Bradford
Infant Mortality Rate
Blackburn with Preston CD England and
18 Bradford MCD Kirklees MCD Pendle CD
Darwen UA Wales
16
14
12
10
Rate
8
6
4
2
0
1999-2001 2000-2002 1999-2001 2000-2002 1999-2001 2000-2002 1999-2001 2000-2002 1999-2001 2000-2002 1999-2001 2000-2002

14. Comparative Infant Mortality Rates for Areas with Similar
Levels of Deprivation
Infant Mortality Rate
12 Bradford MCD Doncaster MCD
Rochdale MCD Leicester UA Mansfield CD England and Wales
10
8
Rate
6
4
2
0
1999-2001 2000-2002 1999-2001 2000-2002 1999-2001 2000-2002 1999-2001 2000-2002 1999-2001 2000-2002 1999-2001 2000-2002

15. Low birth weight (less than 2500g) rate by ward 1993 -
2003

16. MATERNAL UTEROPLACENTAL PLACENTAL FETAL
DIET BLOOD FLOW TRANSFER GENOME
Nutrient demand exceeds supply
FETAL UNDERNUTRITION
BRAIN SPARING DOWN REGULATION EARLY ALTERED BODY
OF GROWTH MATURATION COMPOSITION
IMPAIRED DEVELOPMENT:  INSULIN/IGF-1 SECRETION  CORTISOL MUSCLE 
BLOOD VESSELS, LIVER, AND SENSITIVITY
KIDNEYS, PANCREAS
HYPERLIPIDAEMIA CENTRAL INSULIN
HYPERTENSION OBESITY RESISTANCE
Type 2 diabetes and CHD

17. Childhood disability
Visual impairment
58% Pakistani children vs 29% White British children
Schwarz et al. Eye 2002;16:S30-34
Deafness
4.7 per 1000 Pakistani children vs 1.4 per 1000 others
Parry G. BACDA report 1996
Cerebral Palsy
5.48 per 1000 in Pakistani children vs 3.18 per 1000 in others
Sinha et al Dev Med Child Neurol 1997 39:259-262

18. District Number of cases
(total 736)
Bradford 50
Birmingham 31
East London & City 25
East Riding 22
Berkshire 19

19. Bundey and Aslam 1993 Eur J Hum Genet 206-219
Empirical risk of death or serious disease
European (n = 2,241) Consanguineous Pakistani (n = 656)
Rate 3.7% (2.92-4.48) 10.2 (7.9-12.5)

20. Platform and nested studies
• We have started recruiting pregnant mothers in March
and babies in May
• We will recruit all newborn babies and their parents born
in BRI or under the care of the BRI over 30 months
(target numbers – 10000)
A platform study:
Most data for the study will be routinely collected data –
health history, demographics, weight, blood samples etc.
This will be supplemented with some specific questions
eg more on maternal diet, more on home circumstances.
“Nested” studies – specific research questions that use the
cohort as the source of their study population.

21. Research aims
– To explore the association between specific risk
factors and exposures in pregnancy and infancy with
infant mortality.
– To describe the differences in foetal growth and birth
weight between ethnic groups and to investigate the
causes of low birth weight in babies of South Asian
origin
– To explore the effect of chemical exposure (air/water/
diet) during pregnancy on the intrauterine growth
– To determine the incidence, causes and predictive
factors for congenital abnormalities

22. Further research
– To investigate the association between dietary
exposure to chemicals with carcinogenic and
immunotoxic properties with childhood cancer and
immune disorders.
– To study infant growth and investigate the effect of
postnatal growth on childhood obesity and markers of
cardiovascular disease in childhood.
– To describe social and ethnic differences in health
status and the effects of ethnic density on health
status and pregnancy outcomes.

24. Data collected
• Demographic/socio-economic
• Family history
• Lifestyle factors – smoking/drugs/alcohol/exercise
• Diet – modified food frequency + targeted
questions re exposures
• Well being – GHQ 28
• Social Capital (on sub set of 2000)
• Clinical: antenatal and medical histories; drugs;
BP; weight; U/S scans.
• Blood: routine; GTT; insulin; DNA extraction

26. Progress so far
• Community awareness
• NHS support
• IT systems
• Questionnaire design
• Biobank
• Advocacy committee
• Fundraising
• Feasibility study
• Pilot phase

27. Benefits.
• Full use of routinely
collected data
• Growth of research activity/ capacity/ skills
and opportunity in the city
• Focus for collaboration within health and
with local government and community
organisations.

28. Main challenges
• Funding
• Data collection – information systems accessible
and compatible
• Differential recruitment and drop-out
• Lack of enthusiasm from staff
• Subject burden
• Reconciling long-term gains and short term
“wins”