Objective: Recent Veterans Affairs (VA) guidelines recommend that persons with stable type 2 diabetes controlled on oral agents or diet therapy perform self-monitoring of blood glucose (SMBG) twice weekly. We assessed the impact of a modification of these guidelines on hemoglobin A1c (HbA1c) and monitoring cost.
Study design: Retrospective, noncrossover clinical trial.
Patients and methods: We instructed persons with type 2 diabetes to perform SMBG testing according to modified adapted VA guidelines. We compared patients' baseline average testing frequency and HbA1c with those obtained during a 6-month interval beginning 2 months after implementation of the modified guidelines. The impact on the cost of monitoring was calculated.
Results: At baseline, 913 of 1,213 SMBG users with diabetes on oral hypoglycemic agents had HbA1c tested (HbA1c = 7.83% +/- 1.34%); their frequency of SMBG was 1.36 +/- 0.95 strips per patient per day. Postimplementation, 974 of 1,278 persons with diabetes had HbA1c tested (HbA1c = 7.86% +/- 1.54%; P= .63 vs baseline); frequency of SMBG decreased by 46% to 0.74 +/- 0.50 strips per patient per day (P < .0001). At baseline, 154 of 254 SMBG users with diabetes on diet therapy had HbA1c tested (HbA1c = 6.85% +/- 0.97%); their frequency of SMBG was 1.07 +/- 0.90 strips per patient per day. Postimplementation, 177 of 282 diet-treated persons with diabetes had HbA1c tested (HbA1c = 6.78% +/- 1.20%; P = .56 vs baseline); frequency of SMBG decreased by 35% to 0.70 +/- 0.51 strips per patient per day (P < .0001). Similar findings were observed in a cohort of 421 drug-treated patients with paired HbA1c data before and after implementation, and a cohort of 50 diet-treated patients with paired HbA1c data. Linear regression analysis showed no significant impact on individuals' HbA1c with reduction in strip use. Average monthly cost savings were $8,800, or $6.37 per patient per month.
Conclusions: This program decreased the frequency of SMBG in persons with type 2 diabetes, resulting in substantial cost savings without affecting glucose control.