Sex as an effect modifier in the association between screen time and depression among US adults with trouble...

This cross-sectional study aimed to examine the association between screen time and depression among US adults with self-reported trouble sleeping and assess whether this association is modified by sex using data from the National Health and Nutrition Examination Survey 2005-2018. A total of 10,435 adults aged 20 years or older who reported trouble sleeping in the past month from the population-based survey representative of the US civilian, noninstitutionalized population were included. Depression was assessed using the Patient Health Questionnaire-9 (PHQ-9). Screen time was estimated as the average daily hours spent watching television/videos and using a computer outside of work. Multivariable logistic regression models were used to calculate adjusted odds ratios (aORs) for depression. Interaction by sex was evaluated on both multiplicative and additive scales. Restricted cubic spline regression assessed nonlinear associations. Among participants with trouble sleeping, 19.7% had depression. Greater screen time was significantly associated with higher odds of depression in women (aOR = 1.09 per hour; 95% CI, 1.05-1.13; P < .001). Women reporting ≥4 h/d of screen time had 53% higher odds of depression compared with those reporting <4 h/d (aOR = 1.53; 95% CI, 1.28-1.84). No significant association was observed in men. The sex interaction was statistically significant (P for interaction = 0.012), with evidence of both multiplicative (odds ratio = 1.44; 95% CI, 1.08-1.91) and additive interaction (RERI = 0.49; attributable proportion = 0.31). Restricted cubic spline analysis indicated sex-specific nonlinear relationships. Results were robust in sensitivity and subgroup analyses. Among adults with trouble sleeping, screen time was positively associated with depression in women but not in men. The significant sex interaction highlights the importance of tailoring behavioral interventions for mental health by sex, especially in populations with sleep disturbances.