Taking this drug might not lower death risk

Turns out, a certain class of diabetes drug may not reduce the risk of death among patients.

According to a research conducted by the Imperial College of London, one class of drug used to treat type II diabetes may not reduce the risk of death when compared with placebo.

The researchers studied three types of diabetes treatment: sodium-glucose cotransporter 2 (SGLT-2) inhibitors, glucagon-like peptide 1 (GLP-1) agonists, and dipeptidyl peptidase 4 (DPP-4) inhibitors.

The team investigated whether these drugs were associated with a lower mortality risk, and conducted a network meta-analysis of 236 trials comparing all the drugs against each other, a placebo, or no treatment at all, and involving 176, 310 patients.

All the drugs lower blood sugar levels but the results revealed that while two of the drugs reduced the risk of death when compared with a placebo, one did not.

Sean Zheng, the lead author of the study, said, "Type II diabetes has become a global epidemic, with more cases than ever before. The three drug classes assessed here are being increasingly prescribed, yet until now there have been no clinical trials studying how these drugs compare to each other, and which type of drug could be the best option for patients."

Type II diabetes is thought to affect 2.8 million people in the UK and 422 million people worldwide. The condition causes levels of sugar in the blood to become too high, usually because of a lack of insulin - the hormone that mops up blood sugar.

Treatments include diet and exercise, but most people also need medication to control blood sugar. The most commonly prescribed drug is called metformin, but if this doesn't work, or triggers side effects, patients are usually offered other drugs.

But although these drugs all lower blood sugar, doctors were unclear if one was more effective than another, explained Zheng, "Patients with type II diabetes are at higher risk of dying from heart attacks or strokes, so we wanted to investigate which of these three treatments are most efficient at preventing death and cardiovascular diseases. Our hope is that in the crowded market that is diabetes medications, patients and their doctors have the necessary information to allow them to make informed decisions about long-term treatment strategies."

The team assessed all randomised-controlled trials - the gold-standard trial that randomly assigns patients to a drug or a placebo pill, or no drug at all - and compared the treatments with each other. The results suggested DPP-4 inhibitor drugs were not associated with a reduced risk of death.

There was no reduction in risk of death from a cardiovascular event for the drugs DPP-4 inhibitors.

Zheng explained that the reasons behind the apparent reduced effectiveness of DPP-4 inhibitors are unclear, though it may be they are simply less powerful than the other two types of medication.

However, he cautioned that further work is now needed to confirm these findings, and stressed that anyone concerned about their drug regimen should consult their healthcare team. There was no evidence that any of the treatments caused harm.

The study appears in the Journal of the American Medical Association (JAMA).