Association of maternal smoking, breastfeeding, and multiple birth with irritable bowel syndrome in older adults: a UK Biobank cohort study.

BACKGROUND

We aimed to investigate associations between three perinatal early-life factors and the risk of irritable bowel syndrome (IBS) in middle-aged and elderly people by using data from UK Biobank.

METHODS

This is a population-based cohort study. Participants who had available data on early-life factors-namely maternal smoking around birth, being breastfed as a baby, and being one of a multiple birth and without IBS at the time of recruitment in UK Biobank-were included.

RESULTS

Among a total of 334,586 subjects, 93,908 (28.07%) were exposed to maternal smoking around birth, 243,778 (72.86%) were breastfed as a baby, and 7,551 (2.26%) were part of a multiple birth. During a median follow-up of 13.58 years, 7,254 participants developed IBS, at a median age of 63 years. The hazard ratios of IBS were 1.22 [95% confidence interval (CI), 1.16-1.28, <0.001], 0.92 (95% CI, 0.87-0.97, =0.002), and 1.22 (95% CI, 1.06-1.40, =0.006) for maternal smoking, breastfeeding, and multiple birth, respectively. The joint effect of any two of these three factors was related to added influence instead of interaction between them. The effect of maternal smoking on IBS was modified by age, while the modifiers of the effect of being breastfed as a baby on IBS were the age and sex of the offspring.

CONCLUSIONS

Participants exposed to maternal smoking around birth and being one of a multiple birth had a higher risk of IBS in middle-aged and elderly stages, while being breastfed as a baby had a protective effect against IBS. Future efforts should be made to validate the results.