Effect of structured self-monitoring of blood glucose, with and without additional TeleCare support, on overall glycaemic control in non-insulin treated Type 2 diabetes: the SMBG Study, a 12-month randomized controlled trial

Abstract

Aim: To examine the impact of structured self-monitoring of blood glucose, with or without TeleCare support, on glycaemic control in people with sub-optimally controlled Type 2 diabetes.

Methods: We conducted a 12-month, multicentre, randomized controlled trial in people with established (>1 year) Type 2 diabetes not on insulin therapy, with sub-optimal glycaemic control [HbA_1c ≥58 to ≤119 mmol/mol (≥7.5% to ≤13%)]. A total of 446 participants were randomized to a control group (n =151) receiving usual diabetes care, a group using structured self-monitoring of blood glucose alone (n =147) or a group using structured self-monitoring of blood glucose with additional monthly 'TeleCare' support (n =148). The primary outcome was HbA_1c at 12 months.

Results: A total of 323 participants (72%) completed the study; 116 (77%) in the control group, 99 (67%) in the self-monitoring of blood glucose alone group and 108 (73%) in the self-monitoring of blood glucose plus TeleCare group. Compared to baseline, the mean HbA_1c was lower in all groups at 12 months, with reductions of 3.3 mmol/mol (95% CI -5.71 to -0.78) or 0.3% (95% CI -0.52 to -0.07; P=0.01) in the control group, 11.4 mmol/mol (95% CI -14.11 to -8.76) or 1.1% (-1.29 to -0.81; P<0.0001) in the group using self-monitoring of blood glucose alone and 12.8 mmol/mol (95% CI -15.34 to -10.31) or 1.2% (95% CI -1.40 to -0.94; P<0.0001) in the group using self-monitoring of blood glucose plus TeleCare. This represents a reduction in HbA_1c of 8.9 mmol/mol (95% CI -11.97 to -5.84) or 0.8% (95% CI -1.10 to -0.54; P≤0.0001) with structured self-monitoring of blood glucose compared to the control group. Participants with lower baseline HbA_1c , shorter duration of diabetes and higher educational achievement were more likely to achieve HbA_1c ≤53 mmol/mol (7.0%).

Conclusions: Structured self-monitoring of blood glucose provides clinical and statistical improvements in glycaemic control in Type 2 diabetes. No additional benefit, over and above the use of structured self-monitoring of blood glucose, was observed in glycaemic control with the addition of once-monthly TeleCare support. (Clinical trial registration no.: ISRCTN21390608).

Figure 1

Study design flow chart. QoL, quality of life; SMBG, self‐monitoring of blood glucose; T2DM, type 2 diabetes.

Figure 2

Consort diagram. SMBG, self‐monitoring of blood glucose.

Figure 3

Comparison of mean (sem) HbA_1c between (a) the control and combined SMBG groups and (b) the three groups over the 12‐month study period.

Figure 4

Achieving a target HbA_1c ≤53 mmol/mol (7%). The graph shows time interval to event (achieving HbA_1c ≤7% without relapse). Significant covariates were HbA1c concentrations at baseline, duration with diabetes and attainment of higher education. *One missing value with one of the significant covariates: education. HR, hazard ratio; SMBG, self‐monitoring of blood glucose.