Self-monitoring of blood glucose levels in patients with non-insulin treated type 2 diabetes does not confer any clinical benefit, a recent meta-analysis, published in the BMJ, has concluded.

The studies included were randomised controlled trials in patients with non-insulin treated type 2 diabetes comparing an intervention using self-monitoring of blood glucose with clinical management not using self-monitoring.

Trials published from 2000 onwards with at least 80 patients were deemed eligible. A total of 2,552 patients were randomised in the six trials included.

Subgroup analyses were carried out for age, gender, previous use of self-monitoring, duration of diabetes, and levels of glycated haemoglobin (HbA1c) at baseline.

There was a mean reduction in HbA1c level of 2.7 mmol/mol (95% CI: 1.6–3.9) for those using self-monitoring of blood glucose compared with no self-monitoring at six months. The mean reduction in HbA1c level between groups was 2.0 mmol/mol (95% CI: 0.9–3.2) at three months (five trials) and 2.5 mmol/mol (95% CI: 0.9–4.1) at 12 months (three trials).

The difference in HbA1c levels between groups was not affected by age, baseline HbA1c level, gender, and duration of diabetes. No changes occurred in blood pressure or total cholesterol level.

Blood glucose monitoring in type 2 diabetes patients is often a source of some contention between patients and their GPs and the GPs and PCT medicines management groups.

Patients seem to like the reassurance of knowing what their blood glucose is doing whereas clinicians are not convinced that regular testing is necessary to improve wellbeing and outcomes and may feel it is an expense that the NHS cannot afford.

Despite a small, albeit significant, reduction in HbA1c level in the self-monitoring group the authors conclude that the evidence from this meta-analysis was not convincing for a clinically meaningful effect on clinical management.

This should provide further reassurance for clinicians advising patients that regular monitoring of blood glucose in type 2 diabetes patients who are not taking insulin is unnecessary.

Dr Peter Savill

• Farmer AJ, Perera R, Ward A et al. Meta-analysis of individual patient data in randomised trials of self monitoring of blood glucose in people with non-insulin treated type 2 diabetes. BMJ 2012;344.e486