Geographic and Racial/Ethnic Variation in Glycemic Control and Treatment in a National Sample of Veterans with Diabetes
Methods: A retrospective cohort study was conducted in a national cohort of 1,140,634 veterans with diabetes, defined as two or more diabetes ICD-9 codes (250.xx) across inpatient and outpatient records. Main exposures of interest included 125 VA Medical Center (VAMC) catchment areas as well as race-ethnic group. The main outcome measure was HbA1c level dichotomized at ≥ 8.0% (≥ 64 mmol/mol).
Results: After adjustment for age, gender, race-ethnic group, service-connected disability, marital status and the van Walraven Elixhauser comorbidity score, the prevalence of uncontrolled diabetes varied by VAMC catchment area with values ranging from 19.1% to 29.2%. Moreover, these differences largely persisted after further adjusting for medication use and adherence as well as utilization and access metrics. Racial-ethnic differences in diabetes control were also noted. In our final models, compared to non-Hispanic whites, non-Hispanic blacks (OR: 1.11; 95% CI: 1.09-1.14) and Hispanics (OR: 1.36; 95% CI: 1.09-1.14) had higher odds of uncontrolled HBA1C level.
Conclusions: In a national veteran diabetes cohort, we found geographic as well as racial-ethnic differences in diabetes control rates that were not explained by adjustment for demographics, comorbidity burden, use or type of diabetes medication, healthcare utilization, access metrics, or medication adherence. Moreover, disparities in sub-optimal control appeared consistent across most but not all VAMC catchment areas with non-Hispanic black and Hispanic veterans having a higher odds of sub-optimal diabetes control than non-Hispanic white veterans.