Sulfonylureas as second line treatment for type 2 diabetes

Sulfonylureas and insulin were the cornerstone of diabetes management until 1998 when metformin became recommended as initial treatment by the American Diabetes Association and the European Association for the Study of Diabetes.1 Before 2008, treatments for diabetes were often approved on the basis of their ability to lower glycated haemoglobin (HbA1c) by 0.5% (5.5 mmol/mol) or other surrogate outcomes. After the controversy surrounding cardiovascular risk associated with thiazolidinediones, regulatory agencies such as the US Food and Drug Administration and the European Medicines Agency issued guidance for industries to evaluate the cardiovascular safety of antidiabetes drugs.23

Sulfonylureas have a consistent association with a higher risk of cardiovascular disease and hypoglycaemia compared with metformin.45 Despite this increased risk they remain the second most common initial treatment for diabetes and when combined with metformin, the most common combination regimen. Many people who are initially prescribed metformin either add or switch to a sulfonylurea owing to increased …