Doubts over DIY glucose monitoring

THE clinical benefits and cost-effectiveness of non-insulin treated type 2 diabetes patients monitoring their own blood glucose has been thrown into doubt by two studies showing it failed to improve glycaemic control and adversely affected quality of life.

A UK randomised trial involving 184 people with newly diagnosed type 2 diabetes found no significant difference in HbA_1c levels or the incidence of hypoglycaemia after comparing patients who undertook blood glucose measurements eight times a week for one year with a non-monitoring group.

Self-monitoring was also associated with higher levels of reported depression and anxiety (BMJ, online 17 April).

“The negative effect might relate less to feelings of power­lessness in the face of high blood glucose readings than to the enforced discipline of regular monitoring,” the authors said.

A prospective economic analysis among 453 patients with non-insulin treated type 2 diabetes also found self-monitoring was significantly more expensive than routine care. Researchers estimated intensive self-monitoring cost an additional $195 per patient every year.

Professor Duncan Topliss, director, Department of Endocrinology and Diabetes at The Alfred Hospital in Melbourne said: “These... clearly show that we do need to rethink slavish use of this technique.”

He described HbA_1c as a “good surrogate marker” for long-term microvascular outcomes and advocated HbA_1c over self-monitoring in most non-insulin type 2 diabetes patients.

An accompanying editorial said self-monitoring and might carry an “opportunity cost” with attention better directed to more effective disease control measures such as blood pressure control and smoking cessation.

However, he said until a large randomised trial was conducted, GPs should discuss the value of self-monitoring on a patient-by-patient basis.