Objectives: Atopic dermatitis (AD) is a chronic inflammatory skin condition that not only impairs physical health but also significantly affects psychological well-being and socio-economic productivity. Emerging evidence suggests that sleep disturbances may play a key mediating role in the development of mental health symptoms in individuals with AD. Building on this, we hypothesized that sleep disturbances also mediate the relationship between AD severity and quality of life (QoL), work productivity, and daily activities. We conducted a mediation analysis to explore these pathways in adults with AD.

Methods: A cross-sectional study was conducted in Greece during January-September 2023. Study participants were adult members of the patients’ association EPIDERMIA, diagnosed with AD. Self-perceived disease severity, insomnia, depression, anxiety, QoL, and work/activity impairment were assessed using validated tools: the Patient-Oriented Eczema Measure (POEM), Athens Insomnia Scale (AIS-8), Patient Health Questionnaire-9 (PHQ-9), Generalized Anxiety Disorder-7 (GAD-7), Dermatology Life Quality Index (DLQI), and Work Productivity and Activity Impairment (WPAI) questionnaire. Mediation analysis followed Imai et al.'s framework, using STATA 17.0 and adjusting for age, sex, and BMI.

Results: The analysis included 147 patients (mean ± SD age 37.8 ± 12.7 years; 56% female; mean ± SD BMI 25.6 ± 4.7 kg/m²). Insomnia mediated 115%, 108%, 55%, 78%, and 65% of the effect of AD severity on depression, anxiety, QoL, work productivity, and activity impairment, respectively. Sensitivity analyses showed that a moderate-to-strong unmeasured confounder (ρ > 0.46-0.68) would be required to nullify the observed indirect effects. These findings support a robust mediating role of insomnia, although the cross-sectional design limits causal inference.

Conclusions: Our findings suggest that insomnia is a key mediator in the pathway from AD severity to adverse psychological, functional, and socio-economic outcomes. Targeting sleep disturbances may offer a promising strategy to improve the overall well-being of individuals with AD.