UK researchers used the General Practice Research Database to obtain data on 84,622 patients with a diagnosis of type 2 diabetes. They defined each patient by treatment regimen, with five different regimens included: metformin monotherapy, sulfonylurea monotherapy, insulin monotherapy, metformin plus sulfonylurea and insulin plus metformin.
Patients on insulin monotherapy were over two times more likely to die compared to those on metformin alone, and were 73% more likely to suffer a major adverse cardiac event compared to patients on metformin. Insulin was also associated with a three-and-a-half times increase in risk of renal complications, compared to metformin monotherapy.
What does it mean for GPs?
The authors concluded that there is a ‘clear need to review the way in which exogenous insulin is used in people with type 2 diabetes and to establish in detail the risk-benefit profile at differing stages of the natural history of the disease.’
Dr Colin Kenny, GP in County Dromore and a member of the Primary Care Diabetes Society: ‘This paper is interesting but commonly primary care teams are faced with little choice but to use insulin in patents with high HbA1c levels. There is also a sense that in overweight people with diabetes, GLP-1 agonists are gaining considerable traction. It would be interesting to speculate if the increased risks from insulin are a direct action of the insulin itself, or from weight gain associated, or the fact it is initiated much later in the UK, in more advanced patents.’