Racial and Ethnic Differences in Medication Initiation Among Adults Newly Diagnosed with Type 2 Diabetes

Objective Given persistent racial/ethnic differences in type 2 diabetes outcomes and the lasting benefits conferred by early glycemic control, we examined racial/ethnic differences in diabetes medication initiation during the year following diagnosis. Methods Among adults newly diagnosed with type 2 diabetes (2005-2016), we examined how glucose-lowering medication initiation differed by race/ethnicity during the year following diagnosis. We specified modified Poisson regression models to estimate the association between race/ethnicity and medication initiation in the entire cohort and within subpopulations defined by HbA1c, BMI, age at diagnosis, comorbidity, and neighborhood deprivation index (a census tract-level socioeconomic indicator). Results Among the 77,199 newly diagnosed individuals, 47% started a diabetes medication within 12 months of diagnosis. The prevalence of medication initiation ranged from 32% among Chinese individuals to 58% among individuals of Other/Unknown races/ethnicities. Compared to White individuals, medication initiation was less likely among Chinese (relative risk: 0.78 (95% confidence interval 0.72, 0.84)) and Japanese (0.82 (0.75, 0.90)) individuals, but was more likely among Hispanic/Latinx (1.27 (1.24, 1.30)), African American (1.14 (1.11, 1.17)), other Asian (1.13 (1.08, 1.18)), South Asian (1.10 (1.04, 1.17)), Other/Unknown (1.31 (1.24, 1.39)), American Indian or Alaska Native (1.11 (1.04, 1.18)), and Native Hawaiian/Pacific Islander (1.28 (1.19, 1.37)) individuals. Racial/ethnic differences dissipated among individuals with higher HbA1c values. Conclusions Initiation of glucose-lowering treatment during the year following type 2 diabetes diagnosis differed markedly by race/ethnicity, particularly for those with lower HbA1c values. Future research should examine how patient preferences, provider implicit bias, and shared decision-making contribute to these early treatment differences.