OBJECTIVES: To examine whether social support and race/ethnicity moderate the association between major depressive disorder (MDD) and quality of life (QoL).

METHODS: Data are from the 2021 US National Health and Wellness Survey. QoL was estimated using the Short-Form Six Dimensions utility index score (SF-6D index). The Patient Health Questionnaire (PHQ-9) was used to screen for MDD [positive screen = PHQ-9 ≥ 10]. We measured total social support using the Modified Medical Outcomes Study Social Support Survey. Self-reported race/ethnicity was categorized as White, Black/African American, Hispanic, Asian, or another race. Generalized linear modeling was used to examine covariate-adjusted relationships between SF-6D index, MDD, social support, and race/ethnicity. We estimated main effects then modeled a three-way interaction between depression status, social support, and race/ethnicity. If the interaction was statistically significant (α < 0.05), we probed the interaction by plotting estimated slopes.

RESULTS: Our analysis included 70,330 respondents, of which 21.6% (n = 15,285) indicated MDD. Most respondents identified as White (68.1%), followed by Hispanic (12.4%), Black/African American (9.0%), Asian (6.9%), and another race (3.6%). The interaction between depression, social support, and race/ethnicity was significant (p<0.0001). Among individuals without MDD, social support was associated with a significant linear increase in QoL across all racial/ethnic groups (p values < 0.0001), and average SF-6D index scores within race/ethnicity groups converged at higher levels of social support. Among individuals with MDD, there was a positive linear relationship between social support and QoL among respondents who identified as another race (β = 0.002, p < 0.001). However, for White respondents, social support was inversely related to QoL (β = -0.001, p <0.001).

CONCLUSIONS: The potential to mitigate the negative consequences of depression via social support may differ across all racial/ethnic groups. Thus, understanding the burden of depression may require the consideration of broader contextual factors.