Parchman ML (VERDICT, South TX Veterans Health Care System; University of Texas), Wang CP
(VERDICT; University of Texas)
To examine the relationships between patient characteristics and time to insulin initiation among veterans with poorly controlled type 2 diabetes.
Subjects were veterans with a diagnosis of type 2 diabetes in both FY99 and FY00, with at least one primary care visit each year from FY99-FY06 within a local VA health care system. The sample was restricted to those who completed the Long Health Survey (LHS) and had at least one A1c > = 8.0% without insulin use prior to the elevated A1c. The outcome of interest was the time from the first elevated A1c (baseline) until insulin initiation. Predictors included patients’ age, race/ethnicity, A1c value at baseline, BMI, diabetes duration, and number of classes of oral hypoglycemics at baseline.
Of the 158,062 who had type 2 diabetes at least one primary care visit each year and participated in the LHS, 93,181 had at least one elevated A1c, and 22,841 of those had no prior insulin use and subsequently filled a prescription for insulin. The mean time between an elevated A1c and insulin initiation was 2 years 8 months (S.D. 1 year 9 months). After 6 years, 37% were on insulin. As age, BMI, diabetes duration, number of classes of oral hypoglycemics, and baseline A1c increased, so did the hazard rate for insulin initiation. The strength of the relationships between insulin initiation and both diabetes duration and BMI was attenuated by an increase in the number of classes of hypoglycemics. Kaplan-Meier curves reveal a slower initial rate of insulin initiation for those on three classes of hypoglycemics compared to those on one or two classes.
Significant delays exist for insulin initiation among veterans with poorly controlled type 2 diabetes. Although number of classes of oral hypoglycemics predicts insulin initiation, patients on three classes of oral medication experience early delays compared to those on one or two classes.
Delays in insulin initiation may reflect patient resistance or clinician reluctance to prescribe insulin until all oral options are exhausted. Primary care clinicians and patients need more support to initiate insulin earlier for poor diabetes control.