Risk factors for nocturnal enuresis in school-age children

Although nocturnal enuresis is common in children, its etiology is multifactorial and not fully understood. We evaluated potential risk factors for presence and severity of nocturnal enuresis.

A validated, reproducible questionnaire was distributed to 8,230 school children in Sydney, Australia. Nocturnal enuresis was defined as any wetting in the previous month and categorized as mild (1 to 6 nights), moderate (7 or more nights but less than nightly) or severe (nightly).

Parents of 2,856 children (mean +/- SD age 7.3 +/- 1.3 years) completed the questionnaire (response rate 35%). Overall prevalence of nocturnal enuresis was 18.2%, with 12.3% of patients having mild, 2.5% moderate and 3.6% severe enuresis. Multivariate analysis showed that daytime incontinence (OR 4.8, 95% CI 2.9 to 7.9), encopresis (OR 2.7, 95% CI 1.6 to 4.4), bladder dysfunction (OR 3.6, 95% CI 2.4 to 5.3) and male gender (OR 2.0, 95% CI 1.3 to 3.1) were associated with severe nocturnal enuresis after adjustment for age. Emotional stressors (OR 2.3, 95% CI 1.2 to 4.2) and social concerns (OR 2.4, 95% CI 1.2 to 4.5) were associated with moderate nocturnal enuresis only.

Encopresis and daytime incontinence are significant modifiable risk factors for nocturnal enuresis. Expressed as population attributable risk, 23% of nocturnal enuresis is associated with encopresis and daytime incontinence. Psychosocial factors appear to contribute to moderate but not severe nocturnal enuresis.