Objective: To examine previously cited early risk factors for inflammatory bowel disease.
Design: The 1946 National Survey of Health & Development (NSHD) and the 1958 National Child Development Study (NCDS) are on-going, longitudinal birth cohort studies. A nested case-control design was used combining data from both cohorts; eight controls per case, matched for gender and social class, were selected randomly.
Methods: Data concerning maternal infection in pregnancy (NCDS only), childhood infection (measles, mumps and whooping cough), birth order, appendicectomy, breast-feeding and measures of poor housing conditions in childhood were analysed. In both cohorts, the member's hospital physician or medical records were used to confirm the diagnosis.
Results: Twenty-six cases of Crohn's disease and 29 cases of ulcerative colitis were identified. No significant association was found between the development of Crohn's disease or ulcerative colitis and any of the studied factors. There was a trend that those with Crohn's disease were more likely not to have been breast-fed (OR 0.4, 95% CI 0.15-1.03) and not to have had an appendicectomy (OR < 1.00). The opposite was true of those with ulcerative colitis (OR 2.76, 95% CI 0.86-9.81 and OR 2.34, 95% CI 0.69-7.46, respectively). The prevalence of inflammatory bowel disease was 5.12/1000 by the age of 43 years in NSHD and 2.02-2.54/1000 by the age of 33 years in NCDS.
Conclusions: The prevalence of inflammatory bowel disease in these cohorts is among the highest recorded in Europe. Childhood factors may be different for those with Crohn's disease and ulcerative colitis. These cohorts will be increasingly valuable data sources.