Effect of the Frequency of Self-Monitoring Blood Glucose in Patients with Type 2 Diabetes Treated with Oral Antidiabetic Drugs—A Multi-Centre, Randomized Controlled Trial

OBJECTIVE: Recommendations on the frequency of self-monitoring of blood glucose (SMBG) vary widely among physicians treating patients with type 2 diabetes (T2D). Aim of this study was to investigate two testing regimen of SMBG in patients with stable metabolic control. RESEARCH DESIGN AND METHODS: Patients with T2D treated with oral antidiabetic drugs were randomized to two groups: either one SMBG (low) or four SMBG (high) per week. Subjects were followed up after 3, 6 and 12 months. Primary outcome parameter was the change in HbA1c between baseline and 6 months. Primary outcome criterion was tested by a one-sided t- test for non- inferiority. Secondary outcome parameters were safety, compliance and HbA1c at 3 and 12 months. RESULTS: There were no differences in the 202 subjects for demographic and sociodemographic parameters and drug treatment. HbA(1)c (%) at baseline was similar in both groups (7.2+/-1.4 vs. 7.2+/-1.0). Non- inferiority was demonstrated for the low group (p = 0.0022) with a difference from baseline to 6 months of 0.24 in the low and of 0.16 in the high group. Compliance with the testing regimen was 82-90% in both groups. There were no statistical significant differences for compliance, HbA(1)c at 3 and 12 months and serious adverse events (SAE). CONCLUSION: One SMBG per week is as sufficient and safe as four SMBG per week to maintain HbA(1)c in non-insulin treated T2D close to metabolic target. The results of this study are in contrast to current international consensus guidelines. TRIAL REGISTRATION: Controlled-Trials.com ISRCTN79164268.