Epidemiology Research Assistant Pfizer Inc. New York, United States
Background: Racial and ethnic minorities are disproportionately impacted by type 2 diabetes (T2DM) and its associated complications. The relationship between social determinants of health (SDOH) and diabetes severity within historically marginalized groups remains largely unexplored and warrants further investigation.
Objectives: To evaluate the association between race and ethnicity and T2DM severity, adjusting for confounding variables.
Methods: This was a population-based retrospective cohort study among adults (18+) diagnosed with T2DM in the Optum Electronic Health Records (EHR) database between 2007-2019. Patients with ≥ 1 inpatient or ≥ 2 outpatient diagnosis codes of T2DM, separated by at least 30 days apart, and ≥ 12 months of continuous insurance enrollment were included for analysis. Last reported glycated hemoglobin (A1c) level ≥9 (binary variable) was the main outcome of interest and served as a proxy for diabetes severity.
Multivariable logistic regression was used to evaluate the association between Black, Asian, and Hispanic populations vs. non-Hispanic Whites (reference) and diabetes severity (A1c ≥9, yes/no) using odds ratios (OR) and 95% confidence intervals (CI). Regression models were sequentially adjusted for 1) demographic and SDOH characteristics, 2) clinical factors, and 3) health care utilization and quality of diabetes health care.
Results: Out of 1,316,123 patients with T2DM, n=667,087 (50.7%) had an A1c ≥9. Non-Hispanic Whites comprised 77.49% of the T2DM population, followed by 15.86% non-Hispanic Black, 4.81% Hispanic, and 1.84% non-Hispanic Asian groups.
After adjusting for SDOH and clinical variables, Hispanic and non-Hispanic Black patients had 41% and 26% greater odds of having an A1c ≥9 compared with non-Hispanic Whites (OR=1.41 [95% CI: 1.36, 1.45], 1.26 [95% CI: 1.23, 1.28] respectively). Contrastingly, non-Hispanic Asian populations had 14% lower odds of having an A1c ≥9 compared with non-Hispanic White patients (OR=0.86 [95% CI: 0.82, 0.91]). Younger patients (aged 18-44 and 45-64) consistently had a higher odds of having an A1c ≥9 compared to those aged 65+ (OR= 4.05 [95% CI: 3.95,4.16], 2.24 [95% CI: 2.20, 2.29], respectively). In sensitivity analyses, similar racial and ethnic patterns in disease severity risk were observed in models utilizing outcomes of A1c ≥7.5 and A1c ≥8.
Conclusions: This study suggests that race, ethnicity, and age are consistent drivers of diabetes severity outcomes, after accounting for other social, clinical, and healthcare-related factors that impact health status. Additional analyses that include alternative measures of T2DM severity and dimensions of SDOH are needed to corroborate and expand upon these findings.