Systematic Review of the Benefits of Self-Monitoring of Blood Glucose on Glycemic Control in Type 2 Diabetes Patients

Abstract

Background: The benefit of self-monitoring of blood glucose (SMBG) in improving glycemic control in type 2 diabetes has been controversial. This systematic review evaluated the evidence of benefit of SMBG on glycemic control in non–insulin-treated type 2 diabetes. Methods: Clinical trials of SMBG were identified through electronic searches (MEDLINE, EMBASE, and The Cochrane Library) up to and including September 2007. Studies were included if they met the following inclusion criteria: (1) randomized controlled trial comparing SMBG against non-SMBG in type 2 diabetes, (2) included non–insulin-dependent patients only, and (3) hemoglobin A1c (HbA1c) reported as an outcome measure. The efficacy was estimated with the mean difference in the changes of HbA1c from baseline to final assessment between the SMBG and the non-SMBG groups. Results: SMBG was effective in reducing HbA1c in non–insulin-treated type 2 diabetes (pooled mean difference −0.24%; 95% confidence interval [CI] −0.37% to −0.12%; P = 0.0002). HbA1c decreased significantly in the SMBG subgroup where the results of SMBG were used to modify therapeutic regimens (pooled mean difference −0.27%; 95% CI −0.41% to −0.14%; P < 0.0001). In contrast, there was no significant difference in effects between the SMBG subgroup without the use of its results to modify diabetes management and the non-SMBG group (pooled mean difference −0.12%; 95% CI −0.32% to 0.08%). Conclusions: The evidence suggests the beneficial effect of SMBG in improving glycemic control in non–insulin-treated type 2 diabetes as demonstrated by the reduction of HbA1c levels. Specifically, SMBG proved to be useful only when SMBG results were used to adjust therapeutic regimens.