Examining causal pathways between family adversity and soiling: a prospective cohort study

We aimed to examine the associations between family adversity in infancy and subsequent daytime soiling at primary school age. We also examined factors on the causal pathway between family adversity and soiling, specifically the child's emotional/behaviour problems and constipation.

This prospective cohort study included children from the Avon Longitudinal Study of Parents and Children (N=10 033) with data on the Family Adversity Index (FAI; birth to age 2), daytime soiling at age 7.5, emotional/behaviour problems at age 4, and constipation at age 6. We examined the relationships between the FAI, soiling, emotional/behaviour problems and constipation. We then evaluated the mediating effects of emotional/behaviour problems and constipation. All analyses were adjusted for child and family-related confounders.

Daytime soiling occurred in 7% of children. A one-unit increase in infancy FAI was associated with increased odds of 12% for daytime soiling at age 7.5 (OR 1.12, 95% CI 1.07 to 1.17), emotional/behaviour problems score at age 4 (beta 0.52, 95% CI 0.47 to 0.58) and increased odds of constipation at age 6 (OR 1.07, 95% CI 1.03 to 1.11). The presence of constipation at age 6 was strongly associated with increased odds of soiling at age 7.5 (OR 3.34, 95% CI 2.68 to 4.16). There was weak evidence that the associations between FAI and daytime soiling were mediated by emotional/behaviour problems and constipation (OR_{natural_indirect_effect} 1.03, 95% CI 0.99 to 1.07).

Clinicians should be aware that exposure to family adversity in the early years places children at greater risk of subsequent constipation and soiling.