Metformin in advanced chronic kidney disease: Are current guidelines overly restrictive?

Abstract

Type 2 diabetes mellitus and chronic kidney disease (CKD) frequently co-exist and the increasing burden of both conditions is a global concern. Metformin is established as the first-line treatment for type 2 diabetes because it is associated with improved cardiovascular outcomes and a reduced risk of hypoglycaemia compared with other treatment options. Patients with CKD may benefit in particular because they are at high risk of both cardiovascular disease and hypoglycaemic episodes. However, the use of metformin is restricted in this population due to the concerns over lactic acidosis. Recent reviews have evaluated this risk and concluded that current guidelines for prescribing metformin in CKD may be too restrictive. This narrative review considers this evidence further, but also examines the strength of evidence that favours the use of metformin in CKD patients.