Life course study of the etiology of self-reported irritable bowel syndrome in the 1958 British birth cohort.

OBJECTIVE

Irritable bowel syndrome (IBS) is a common gastrointestinal disorder with unknown etiology. This is the first study to use a life course approach to examine premorbid risk markers for self-reported IBS in a UK birth cohort.

METHODS

Cohort study using the 1958 British birth cohort, which included 98.7% of births in 1 week in England, Wales, and Scotland. The outcome was self-reported IBS by the age of 42 years, classified with onset after 24 years and onset after 34 years. Childhood psychopathology was assessed by the Rutter scales, and adulthood psychopathology was assessed by the Malaise Inventory.

RESULTS

The prevalence of self-reported IBS in this cohort was 8.4% by 42 years (95% confidence interval [CI]=8.2-8.6). In multivariate analyses, being female (odds ratio [OR]=2.00, 95% CI=1.67-2.36), reporting 1 week to 1 month of school absence for ill health at 16 years (OR=1.27, 95% CI=1.03-1.56) and psychopathology at 23 years (OR=1.25, 95% CI=1.01-1.54) and 33 years (OR=2.20, 95% CI=1.74-2.76) were associated with an increased odds for IBS. Prospectively measured childhood adversity showed no significant association.

CONCLUSIONS

This is the first study to show a long-term prospective link between premorbid psychopathology and later self-reported IBS, in agreement with previous findings on chronic fatigue syndrome. There is no evidence that prospective measures of childhood adversity are risk markers for IBS, and there is weak evidence that prospective measures of childhood illness at 16 years are risk markers for IBS, differing to results from the same cohort for psychopathology, chronic fatigue syndrome, and chronic widespread pain. This study also does not replicate the findings of retrospective studies examining the etiology of IBS.