The effect of a structured self-monitoring blood glucose regimen on glycaemic control for type 2 diabetes patients using insulin

Abstract

Background: Self-monitoring of blood glucose (SMBG) can inform on the timing of hyperglycaemia; however there is currently no standardised approach to utilise these data to improve glycaemic control in type 2 diabetes patients.

Aims: To assess the efficacy of structured blood glucose testing in guiding an insulin titration algorithm in poorly controlled, insulin-treated type 2 diabetes patients. The secondary aim was to compare change in HbA1c between the study subjects and matched controls receiving standard treatment.

Methods: This six-month prospective intervention recruited 39 poorly controlled (HbA1C ≥ 8.5% or 69.4 mmol/mol), type 2 diabetes subjects using twice-daily biphasic insulin from two public hospitals in Tshwane, South Africa. Patients were asked to perform structured SMBG over 4 weeks and return monthly for consultations where physicians titrated insulin doses using a standardised algorithm guided by the data collected. Post-hoc analysis was performed to assess glycaemic control of study participants compared to those receiving standard treatment.

Results: It was found that mean HbA1c decreased over the study period by 1.89% (95% CI: -2.46 to -1.33, p-value<0.001). Mean SMBG and mean fasting plasma glucose (FPG) decreased by 1.6 mmol/L (95% CI: -2.5 to -0.6 mmol/L, p-value: 0.002) and 1.5 mmol/L (95% CI: -2.2 to -0.2 mmol/L, p-value: 0.024), respectively. Hypoglycaemic event rate (≤3.9 mmol/L) was 33.08 events per patient-year. Total daily insulin use increased by a mean 40.12 units.day-1 (SE: 7.7, p-value<0.001); weight increased by an average 3.98 kg (95% CI: 2.56 to 5.41, p-value <0.001) over the study period. Study participants were found to have a greater mean (SE) reduction of 0.777% (0.404) in HbA1c compared to patients receiving standard care, which fell short of statistical significance (95% CI: -1.569 to 0.015%, p-value: 0.054) due to lack of power (56.5%) in the post-hoc comparison.

Conclusion: A structured SMBG programme that advises monthly algorithmic insulin titration can improve glucose control in type 2 diabetes patients using insulin, with moderate hypoglycaemic events and weight gain.