Severity of eczema and mental health problems in Japanese schoolchildren: The ToMMo Child Health Study

Background: The association between eczema and mental health problems in schoolchildren has been underexplored. We aimed to investigate this association with the validated questionnaires. Methods: Of 46,648 invited children, we analyzed 9954 (21.3%) in the 2nd to the 8th grades from the ToMMo Child Health Study conducted in 2014 and 2015, a cross-sectional survey in Miyagi Prefecture, Japan. We defined eczema status as “normal,” “mild/moderate,” or “severe,” based on the presence of persistent flexural eczema and sleep disturbance, according to the International Study of Asthma and Allergies in Childhood (ISAAC) Eczema Symptom Questionnaire. Clinical ranges of Strengths and Difficulties Questionnaire (SDQ) total difficulties scores and four SDQ subcategories of emotional symptoms, conduct problems, hyperactivity/inattention, and peer problems were defined as scores ≥16, ≥5, ≥5, ≥7, and ≥5, respectively. Results: The mean SDQ total difficulties score significantly increased as eczema status worsened (all P ≤ 0.004 for trend). The OR of scores in the clinical range for SDQ total difficulties were 1.51 (95% CI, 1.31–1.74) for mild/moderate eczema and 2.63 (95% CI, 1.91–3.63) for severe eczema (P < 0.001 for trend), adjusted for sex, school grade, current wheeze, and disaster-related factors, using normal eczema as a reference. The association between severity of eczema and four SDQ subcategories showed a similar trend (all P ≤ 0.017 for trend). Conclusions: We found a significant association between severity of eczema and mental health problems. The presence of eczema was associated with four SDQ subcategories.