Joint association of sedentary behavior and physical activity domains with depression in Korean adults: Cross-sectional study combining four biennial surveys (2016-2022).

Although the increased prevalence of sedentary behavior and insufficient physical activity constitutes a global public health concern, there is limited research on their effects on mental health. We investigated the combined association of sedentary behavior (daily sitting or reclining ≥10 h/day) and physical activity domains (evaluated using the Global Physical Activity Questionnaire, including occupational physical activity, leisure-time physical activity, and transportation-related physical activity) with depression (Patient Health Questionnaire-9, cutoff score: 10). This cross-sectional study utilized biennial data of 21,416 adults (age >20 years) from the Korea National Health and Nutrition Examination Survey waves 7-9 (2016-2022). Joint associations were explored by combining sedentary behavior and each physical activity domain into four levels. Sedentary behavior and occupational physical activity increased the risk of depression, leisure-time physical activity decreased the risk only in men, and transportation-related physical activity showed no significant association. Logistic regression each physical activity domain revealed, for men and women, a significantly higher risk of depression in the sedentary behavior (+)/occupational physical activity (+) group than in the sedentary behavior (-)/occupational physical activity (-) group (odds ratio: 3.05 and 2.66, respectively). The sedentary-behavior (+)/leisure-time physical-activity (-) group showed a significantly higher risk of depression than the sedentary behavior (-)/leisure-time physical activity (+) group (odds ratio: 2.50 and 2.14), and sedentary behavior (+)/transportation-related physical activity (-) group also showed a significantly higher risk of depression compared to the sedentary behavior (-)/transportation-related physical activity (+) group (odds ratio: 1.83 and 1.61). With concurrent exposure to sedentary behavior, the occupational physical activity and lack of leisure time and transportation-related physical activity synergistically increased the risk of depression. Encouraging leisure-time physical activity, minimizing rigorous occupational physical activity, and reducing sedentary behavior may reduce depressive symptoms, and research into specific domains of sedentary behavior and the quantity and quality of transportation-related physical activity is needed.