Association between different sedentary types and risk of depression: A systematic review and dose-response...

To systematically evaluate the prospective association between different types of sedentary behaviors and incident depression, and to quantify any dose-response relationship.

We searched PubMed, Embase, Web of Science, and the Cochrane Library for relevant studies. Data were extracted and the risk of bias was assessed using standard protocols. Random effects models and robust error meta-regression were applied to estimate the associations and dose-response relationships. The certainty of evidence was assessed via the GRADE framework.

Sixteen relevant cohort studies with a total of 166,707 participants were included. Overall, prolonged daily sedentary time modestly increased depression risk. Subgroup analyses revealed the association was stronger in adolescents and in females, but null in adults and males. "Passive-mental" sedentary behavior (screen/TV time) showed significant associations, whereas total sitting time did not. In subgroups by age, a non-linear dose-response relationship was found between sedentary time per day and depression risk in adolescents, with an increase in depression risk when sedentary time exceeded 3.7 h per day; after including only studies with baseline depression exclusion, a non-linear dose-response relationship was also found between total sedentary and TV time and depression risk.

Prolonged daily sedentary behavior (particularly, passive screen or TV exposure) may increase future depression risk, with adolescents and females being more susceptible. Limiting passive sedentary behavior to <4 h/day and TV viewing to <6.75 h/day could represent pragmatic preventive targets.