Associations between aerobic and muscle-strengthening physical activity, joint pain severity, and risk of depressive disorder among adults with arthritis: a large population-based study (Preprint)

<sec> <title>BACKGROUND</title> Depressive disorder is a common comorbidity among adults with arthritis, significantly affecting treatment adherence and quality of life, while physical inactivity is considered a major risk factor for depressive disorder. Although physical activity is known for its benefits, the optimal approach to aerobic activity (AER) and muscle-strengthening activity (MSA) for mitigating depressive disorder in arthritis patients remains unclear, and whether the associations were consistent across joint pain severity needs to be explored. </sec> <sec> <title>OBJECTIVE</title> This study aims to identify the optimal combined AER and MSA frequencies for reducing depression in arthritis adults across joint pain levels. </sec> <sec> <title>METHODS</title> We used data from the Behavioral Risk Factor Surveillance System (BRFSS) surveys from 2015 to 2019. Physical activity was assessed based on self-reported AER and MSA, while joint pain severity was self-reported on a scale from 0 to 10. The primary outcome, depressive disorder, was defined by responses regarding a history of depressive disorder. Logistic regression models were performed to evaluate associations between physical activity, joint pain severity, and depressive disorder, controlling for potential confounders. Multiplicative and additive interactions between physical activity and joint pain severity were tested. </sec> <sec> <title>RESULTS</title> A total of 318,732 participants with arthritis were included in the main analysis. Overall, reaching both AER and MSA at recommended levels was consistently associated with lower odds of depressive disorder across all pain severity categories. Among those experiencing joint pain, a significant dose-response relationship was identified between levels of AER and MSA with depressive disorder. For participants with no or mild joint pain, those conducting ≥300 minutes of AER per week and MSA for 6-7 times per week had the lowest odds of depressive disorder (OR=0.55, 95% CI 0.45-0.66). For those with moderate joint pain, combining 150-299 minutes of AER with 6-7 times of MSA per week had lower odds of depressive disorder (OR=0.58, 95% CI 0.43-0.77). In the severe joint pain group, 150-299 minutes of AER combined with 2-3 days of MSA was associated with the lowest odds of depressive disorder (OR=0.72, 95% CI 0.57-0.90). </sec> <sec> <title>CONCLUSIONS</title> We found that both AER and MSA were associated with reduced odds of depressive disorder across varying joint pain severity, with a combined approach appearing to offer optimal benefits. Higher dose and frequency of AER and MSA were related to lower odds of depressive disorder, especially in individuals with no/mild to moderate joint pain. These findings emphasize the importance of promoting physical activity among arthritis patients to support better mental health. </sec>