Insulin use by diabetics associated with greater risk of dying over a decade compared to other diabetic therapies

Friday, February 8, 2013. In an article published online on January 31, 2013 in The Journal of Clinical Endocrinology & Metabolism, Welsh researchers report an increased risk of adverse effects, cancer and death over a ten year period among diabetics treated with insulin in comparison with other treatments.

Professor Craig J. Currie of Cardiff University and his associates evaluated data from the UK General Practice Research Database, 2000-2010 for 84,622 patients with type 2 diabetes who received glucose-lowering drugs. Subjects were treated with metformin, sulfonylurea drugs, insulin, metformin plus sulfonylureas, or metformin and insulin for no less than 180 days.

Compared with those who used metformin alone, treatment with sulfonylurea drugs was associated with a 43.6 percent greater risk of experiencing an initial adverse cardiac event or cancer, or death from any cause during the decade examined. For insulin alone, the risk was 80 percent higher and for insulin combined with metformin, the risk was 31 percent higher. Among those with no prior history of the events, insulin therapy was associated with nearly twice the risk of heart attack, a 73.6 percent higher risk of major adverse cardiac events, a 43.2 percent greater risk of stroke, a 43.7 greater risk of developing cancer, 3.5 times the risk of kidney complications, and more than twice the risk of neuropathy or dying from any cause in comparison with the risks experienced by those who used metformin.

"By reviewing data from CPRD between 1999 and 2011 we've confirmed there are increased health risks for patients with type 2 diabetes who take insulin to manage their condition," stated Dr Currie, who is affiliated with Cardiff University's School of Medicine.

"Insulin treatment remains the most longstanding blood-glucose-lowering therapy for people with type 2 diabetes, with its use growing markedly in recent years," he noted. "However, with new diabetes therapies and treatments emerging there has been a new spotlight on treatments to ensure what the best and safest form of diabetes treatment is.

"Patients currently being treated with insulin should not, under any circumstances, stop taking their medications, and it is important to emphasize that this report related to only type 2 diabetes which typically starts in older people who are overweight," he cautioned. "Each patient's individual circumstances are different and treatment decisions are managed by their clinician with all of their medical history fully considered."

"Anyone who is concerned should speak to their GP first before taking any action on managing their condition," he added.