In an article published on June 7th, 2016 in the Annals of Internal Medicine, Dr. Shari Bolen and colleagues from Johns Hopkins University compare the effectiveness and safety of most diabetes medications alone and in combination with metformin. They found that metformin, one of the older medications, is still the safest and most effective diabetes medication.
Pharmaceutical companies continue to make new drugs to reduce blood sugar and improve on safety concerns of the older drugs. While adults with diabetes often need more than one medication to control blood sugar, the newer medications do not appear to be safer than the older drugs. In an article published in Annals of Internal Medicine, Dr. Bolen and colleagues compare the effectiveness and safety of most diabetes medications alone and in combination with metformin. They found that metformin, one of the older medications, is still the safest and most effective diabetes medication. They also found that metformin was associated with a lower risk of death from cardiovascular disease than the sulfonylurea medications. Their study supports metformin as first line treatment for adults with type 2 diabetes without a contraindication. The newer medications (glucagon-like-1 receptor agonists and sodium-glucose cotransporter-2 inhibitors) reduced blood sugar similarly to metformin except for a newer class, DPP-4 inhibitors, which had a somewhat smaller effect on reducing blood sugar. Many of the medications also had a favorable effect on weight, including metformin, DPP-4 inhibitors, SGLT-2 inhibitors and GLP-1 receptor agonists. Each class of medications has some safety concerns. Safety concerns discussed include the risk of hypoglycemia with sulfonylureas, the risk of gastrointestinal side effects with metformin and GLP-1 receptor agonists, the risk of heart failure with thiazoldinediones, the risk of yeast infections with SGLT-2 inhibitors, and the risk of hospitalization for heart failure with DPP-4 inhibitors. The complications of untreated diabetes often outweigh these safety concerns, but consumers will need to weigh benefits and risks of the medications with their doctors when making diabetes treatment choices.
This study helps to inform both doctors and consumers. A set of provider and consumer guides will be developed and available from the Agency for Healthcare Research and Quality, which funded this work.
Dr. Bolen is Co-Director of the Population Health group within the Center for Health Care Research and Policy.