ROLE OF GEOGRAPHIC VARIATION IN PATTERNS OF RACIAL/ETHNIC DISPARITIES IN DEPRESSION: RESULTS FROM A LARGE US COHORT OF MID-LIFE AND OLDER ADULTS

Abstract

Introduction There is evidence of racial/ethnic disparities in late-life depression (LLD) burden and treatment in the US. Geographic region may be a novel social determinant of this disparity, yet limited evidence exists regarding the interplay of geographic region with racial/ethnic differences in LLD symptoms, severity and treatment. Methods We conducted a cross-sectional study among participants of the VITAL-DEP (VITamin D and OmegA-3 TriaL-Depression Endpoint Prevention) study, which is ancillary to the VITAL trial of heart disease and cancer prevention. Participants are 25,871 men and women, aged 50+ and 55+ years, with extensive social, demographic, lifestyle, behavioral and health variables ascertained at baseline. Racial/ethnic groups included Non-Hispanic White, Black, Hispanic, Asian and Pacific Islander, and other groups (including Native American/Alaskan Native and other, multiple or unspecified race/ethnicity). Depressive symptoms were assessed using the Patient Health Questionnaire-8 (PHQ-8); participants reported clinician/physician diagnosis of depression and medication and/or counseling treatment for depression. Associations of geographic region with likelihood of LLD were examined using multivariable zero-inflated negative binomial regression; regression models were used to evaluate further the patterns of racial/ethnic disparities in LLD outcomes within geographic regions. Results We included 25,502 participants with depression data: 7066 from Northeast, 7133 from Southeast, 5471 from Midwest, and 5832 from Southwest geographical regions. The mean age was 67.1 years; 12888 [50.5%] were females. There were 17828 [69.9%] non-Hispanic White, 5004 [19.6%] Black, 1001 [3.9%] Hispanic, 377 [1.5%] Asian, and 1292 [5.1%] other race/ethnicity-reporting participants. In the full sample, only Midwest region was significantly associated with likelihood of LLD, compared to Northeast (reference) region (multivariable-adjusted incidence rate ratio (IRR), 95% confidence interval (CI): 0.85, 0.79-0.90); p Conclusions In this large cross-sectional study of diverse older adults in the US, geographic region was significantly associated with late-life depression, and significant variations in the extent of racial/ethnic disparities in depression severity, symptoms and treatment were observed by geographic region. Future longitudinal investigations may clarify the role of geographic region as a novel social determinant of racial/ethnic disparities in LLD. This research was funded by: VITAL-DEP is supported by R01 MH091448