High-potency statins linked to increased risk of diabetes

In the most comprehensive study of its kind, researchers with the Canadian Network for Observational Drug Effect Studies (CNODES) found that patients taking higher strength statins face an increased risk of developing diabetes. Their paper is published in the latest issue of the British Medical Journal (BMJ).

The study found a 15 per cent relative increase in the risk of diabetes within two  years of starting treatment with high potency statins, as compared with low potency statins. Patients included in the study had started statin therapy after experiencing a major cardiovascular event such as a heart attack or stroke.  About two-thirds of these patients were prescribed a high potency statin.

“Although statins are recommended for patients after a heart attack or stroke, these findings tell us that doctors need to consider the possibility that high doses of statins will increase the risk of diabetes in such patients,” says Colin Dormuth, Assistant Professor of Anesthesiology, Pharmacology and Therapeutics at the University of British Columbia, the paper’s lead author.

In absolute terms, the 15 per cent relative increase in risk of diabetes over two years means that one additional case of diabetes was estimated to have occurred for every 350 patients treated with a high potency statin instead of a low potency statin.

“The health consequences of a diabetes diagnosis can be significant,” says Lorraine Lipscombe, a diabetes specialist and Assistant Professor at the University of Toronto, one of the paper’s co-authors. “Following a heart attack or stroke, doctors are more likely to prescribe a high potency statin, but a lower strength statin may be a better choice for many patients.”

Statins are among the most widely used prescription drugs and are proven to be life-saving for patients with heart disease.

Statins considered to be high potency were rosuvastatin (e.g., Crestor) at doses of 10mg or higher, atorvastatin (e.g., Lipitor) at doses of 20mg or higher, and simvastatin (e.g., Zocor) at doses of 40mg or more. All other statins were considered lower potency.

To conduct the study, CNODES researchers from across Canada examined the health records of 136,966 patients who were 40 years of age or older in Canada, the United States, and the United Kingdom. As is its mandate, the Network has the ability to analyze a large amount of anonymous patient data to assess questions of drug safety more reliably than would otherwise be possible in smaller studies.

“This study highlights the importance of the CNODES pan-Canadian collaboration in addressing questions of prescription drug safety,” says Samy Suissa, the Principal Investigator of CNODES and Director of the Centre for Clinical Epidemiology at the Lady Davis Institute at the Jewish General Hospital in Montreal. “The cutting-edge methods used in this study result in better protection of the health of Canadians against inappropriate medication use.”

Manitoba’s site lead for this statins project is Colette Raymond, a scientist at the Manitoba Centre for Health Policy (MCHP), an internationally acclaimed research centre at the University of Manitoba that focuses on population-based health services, public health and population health research.

“It is exciting to be part of the Canadian CNODES collaborative with six other provinces. We are conducting drug safety research once the drugs get into the ‘real world’, using health databases through our universal healthcare system,” says Patricia Martens, distinguished professor at the University of Manitoba and senior scientist at MCHP.

According to Martens, who, along with Dan Chateau at MCHP and Patricia Caetano from Manitoba Health, leads the Manitoba research site for CNODES, the network is providing insights that will improve the health of all Canadians and will be applicable throughout the world.

CNODES is part of the Drug Safety and Effectiveness Network (DSEN), which is funded by the Canadian Institutes of Health Research (CIHR).

MCHP is a research unit in the Department of Community Health Sciences in the College of Medicine, Faculty of Health Sciences at the University of Manitoba. Research scientists and their collaborators at MCHP study health services, population and public health, and the social determinants of health using data from the entire population of Manitoba. Most of the research answers questions of interest to policy makers based on a formal association with Manitoba Health and input from other government departments.

For further information, and to arrange interviews, contact: Tod Hoffman, Research Communications Officer, Lady Davis Institute, at 514-340-8222 x 8661, or 514-433-3500; (thoffman [at] jgh [dot] mcgill [dot] ca)

Or Ilana Simon, Director of Communications & Marketing, College of Medicine, Faculty of Health Sciences, University of Manitoba, 204.789.3427, or 204.295.6777; (ilana [dot] simon [at] med [dot] umanitoba [dot] ca).

Citation: Dormuth CR, Filion KB, Paterson JM, James MT, Teare GF, Raymond CB, Rahme E, Tamim H, Lipscombe L and the Canadian Network for Observational Drug Effect Studies (CNODES)*. Higher Potency Statins and the Risk of New Diabetes: A Multicenter Observational Study of Administrative Databases. To be published online at www.bmj.com on [May 29, 2014]

*CNODES Investigators: Samy Suissa (Principal Investigator); Colin Dormuth (British Columbia);  Brenda Hemmelgarn (Alberta); Gary Teare (Saskatchewan);  Patricia Martens and Patricia Caetano (Manitoba);  David Henry and Michael Paterson (Ontario);  Jacques LeLorier (Québec); Adrian Levy (Nova Scotia); Pierre Ernst (UK General Practice Research Database (CPRD)); Robert Platt (Methods); and Ingrid Sketris (Knowledge Translation).For more about CNODES: www.cnodes.ca.