(E) The Association Between Race, Social Determinants of Health, and Treatment for Major Depressive Disorder (MDD) in a Real-World Cohort

Publication Number: 1004

Background: The relationships between race/ethnicity, social determinants of health and major depressive disorder (MDD) are complex. There is growing interest in understanding the role that social determinants of health, including financial assets, have in contributing to disparities in MDD burden.

Objectives: To describe the social and mental health characteristics of white and black patients diagnosed with MDD in a U.S. real-world cohort.

Methods: Data were derived from the OM1 Major Depressive Disorder Registry (OM1, Boston, MA), a multi-source real-world data network with linked healthcare claims, social determinants of health, and electronic medical records data on U.S. patients with MDD from all 50 states. Patients were included if they had two documented MDD diagnoses within the study period (3/2015 - 2/2020). Patient age, race, sex, insurance type, education, and household income were assessed at the initial diagnosis date (index). In subgroups defined by race and income, mean baseline PHQ-9 scores (as available) and number and percent of patients with mental health care visits and antidepressant prescriptions were assessed in the 12 months after index.

Results: The study included 123,966 black patients [76% female, mean age 51 years (SD=16)] and 1,087,579 white patients with MDD [69% female, mean age 55 years (SD=17)]. Black patients with MDD had a mean household income of $59K (SD=$47K) as compared to $72K (SD=$59K) for white patients, with 14% and 8% having household incomes <$25K, respectively.

For patients with available PHQ-9 at index, the mean score for black patients was higher than for white patients (10.8 vs 8.8; P < .0001). Approximately 1 in 3 black patients (32%) had a PHQ-9 ≥ 15 (moderately severe to severe MDD), versus 22% of white patients. The mean PHQ-9 for patients with incomes < $25K was higher than for patients with incomes ≥ $25K (9.7 vs 8.9; p =0.006). Emergency care (2,358 [1.9%] vs 10,481 [1.0%] p < .0001) and inpatient mental health care use (10,555 [8.5%] vs 56,020 [5.2%]; p < .0001) was higher in black patients while outpatient mental health visits were lower (29,008 [23.4%] vs. 268,622 [24.7%]; p < .0001). Prescription fills for antidepressant therapy in the 12 months after index were significantly lower for black versus white patients (0.9 vs 1.2; p <.0001). Among black patients, antidepressant fills (0.94 vs 0.89; p = 0.02) were higher in patients with household incomes ≥ $25k versus lower.

Conclusions: In a real-world cohort of patients with MDD, black race and socioeconomic disadvantage were associated with increased MDD burden. Improving access to outpatient mental health care may increase opportunities for more effective treatment of depressive symptoms to improve differential outcomes and reduce racial disparities in MDD.