Facility‐level variation in diabetes and blood pressure control in patients with diabetes: Findings from the Veterans Affairs national database

Abstract

Intensive glycemic and blood pressure (BP) control in diabetic patients is associated with improved cardiovascular outcomes. We hypothesized that there is suboptimal glycemic and BP control with significant facility-level variation in patients with diabetes. We identified patients with diabetes receiving care in 130 facilities in the Veterans Affairs Health Care System. We assessed facility-level rates of glycemic (hemoglobin [Hb]A1c <7%), BP (BP <140/90 mmHg), and combined glycemic and BP control (HbA1c <7% and BP <140/90 mmHg), and their facility-level variation in using median rate ratios (MRR). Among 1 103 302 patients with diabetes, 50.2% participants had an HbA1c <7%, 77.5% had a BP <140/90 mmHg, and 39.8% had both, HbA1c <7% and BP <140/90 mmHg. Median facility-level rates were 50.3% (interquartile range [IQR], 47.9%-52.4%) for glycemic control, 78.4% (IQR, 75.2%-80.0%) for BP control, and 39.9% (IQR, 38.14%-42.34%) for combined glycemic and BP control. Unadjusted MRR for glycemic control was 1.61 (95% confidence interval [CI]: 1.51-1.70) which decreased to 1.16 (95% CI: 1.14-1.19) after adjusting for patient and facility-level variables, indicating a 16% variation in glycemic control between 2 identical patients receiving care at 2 random facilities. Unadjusted MRR for BP control was 1.49 (95% CI: 1.41-1.56), which decreased to 1.25 (95% CI: 1.21-1.28), whereas unadjusted MRR for combined glycemic and BP control was 1.59 (95% CI: 1.50-1.68), which decreased to 1.15 (95% CI: 1.13-1.17) after adjustment. Facility-level rates for BP control and glycemic control remain low with significant facility-level variation. Much of this is explained by patient and facility-level variables although 16%, 25%, and 15% variation in glycemic, BP, and combined glycemic and BP control remains unexplained.