Encounter Frequency and Serum Glucose Level, Blood Pressure, and Cholesterol Level Control in Patients With Diabetes Mellitus

Background: More frequent patient-provider encounters may lead to faster control of hemoglobin A(1c) level, blood pressure (BP), and low-density lipoprotein (LDL) cholesterol (LDL-C) level (hereafter referred to as hemoglobin A1c, BP, and LDL-C) and improve outcomes, but no guidelines exist for how frequently patients with diabetes mellitus (DM) should be seen. Methods: This retrospective cohort study analyzed 26 496 patients with diabetes and elevated hemoglobin A(1c), BP, and/or LDL-C treated by primary care physicians at 2 teaching hospitals between January 1, 2000, and January 1, 2009. The relationship between provider encounter (defined as a note in the medical record) frequency and time to hemoglobin A(1c), BP, and LDL-C control was assessed. Results: Comparing patients who had encounters with their physicians between 1 to 2 weeks vs 3 to 6 months, median time to hemoglobin A(1c) less than 7.0% was 4.4 vs 24.9 months (not receiving insulin) and 10.1 vs 52.8 months (receiving insulin); median time to BP lower than 130/85 mm Hg was 1.3 vs 13.9 months; and median time to LDL-C less than 100 mg/dL was 5.1 vs 32.8 months, respectively (P < .001 for all). In multivariable analysis, doubling the time between physician encounters led to an increase in median time to hemoglobin A(1c) (not receiving [35%] and receiving [17%] insulin), BP (87%), and LDL-C (27%) targets (P < .001 for all). Time to control decreased progressively as encounter frequency increased up to once every 2 weeks for most targets, consistent with the pharmacodynamics of the respective medication classes. Conclusions: Primary care provider encounters every 2 weeks are associated with fastest achievement of hemoglobin A(1c), BP, and LDL-C targets for patients with diabetes mellitus.