Joint effects of prescription opioid use and physical activity on depressive symptoms.

Objectives: The possible interaction of prescription opioid use and physical activity with regard to depressive symptoms has not been well studied. This study aimed to investigate the joint effects of prescription opioid use and physical activity on depressive symptoms.

Study Design: Cross-sectional study.

Methods: This cross-sectional study included 29,542 participants from the National Health and Nutrition Examination Survey (2007 to March 2020). Depressive symptoms were evaluated using the Patient Health Questionnaire-9. Multivariable logistic regression models were used to examine the association.

Results: Of the 29,542 adults, 2598 had depressive symptoms (weighted, 7.7%), 1845 used prescription opioids (weighted, 6.0%), and 18,373 (weighted 67.0%) achieved the recommended physical activity. After multivariable adjustment, the odds ratio (OR) of depressive symptoms was 4.06 (95% confidence interval [CI]: 3.28, 5.02) for both prescription opioid use and inactive physical activity compared to those without either condition. No multiplicative interaction was observed for prescription opioid use and inactive physical activity on depressive symptoms (OR = 1.26 [95% CI: 0.87, 1.81]). However, additive interaction was statistically significant between the 2 exposures (relative excess risk due to interaction = 1.34 [95% CI: 0.31, 2.36]; attributable proportion due to interaction = 0.33 [95% CI: 0.12, 0.54]; synergy index = 1.78 [95% CI: 1.12, 2.83]).

Conclusions: Prescription opioid use and inactive physical activity interacted synergistically to affect depressive symptoms.