Disparities in Acute and Chronic Complications of Diabetes Along the U.S. Rural-Urban Continuum.

Objective: To determine the relative hazards of acute and chronic diabetes complications among people with diabetes across the U.S. rural-urban continuum.

Methods: This retrospective cohort study used the OptumLabs Data Warehouse, a deidentified data set of U.S. commercial and Medicare Advantage beneficiaries, to follow 2,901,563 adults (age ≥18 years) with diabetes between 1 January 2012 and 31 December 2021. We compared adjusted hazard ratios (HRs) of diabetes complications in remote areas (population <2,500), small towns (population 2,500-50,000), and cities (population >50,000).

Results: Compared with residents of cities, residents of remote areas had greater hazards of myocardial infarction (HR 1.06 [95% CI 1.02-1.10]) and revascularization (HR 1.04 [1.02-1.06]) but lower hazards of hyperglycemia (HR 0.90 [0.83-0.98]) and stroke (HR 0.91 [0.88-0.95]). Compared with cities, residents of small towns had greater hazards of hyperglycemia (HR 1.06 [1.02-1.10]), hypoglycemia (HR 1.15 [1.12-1.18]), end-stage kidney disease (HR 1.04 [1.03-1.06]), myocardial infarction (HR 1.10 [1.08-1.12]), heart failure (HR 1.05 [1.03-1.06]), amputation (HR 1.05 [1.02-1.09]), other lower-extremity complications (HR 1.02 [1.01-1.03]), and revascularization (HR 1.05 [1.04-1.06]) but a smaller hazard of stroke (HR 0.95 [0.94-0.97]). Compared with small towns, residents of remote areas had lower hazards of hyperglycemia (HR 0.85 [0.78-0.93]), hypoglycemia (HR 0.92 [0.87-0.97]), and heart failure (HR 0.94 [0.91-0.97]). Hazards of retinopathy and atrial fibrillation/flutter did not vary geographically.

Conclusions: Adults in small towns are disproportionately impacted by complications of diabetes. Future studies should probe for the reasons underlying these disparities.