Different types of statin increase the risk of diabetes more than others and should therefore be tailored to patients accordingly, the authors of a large Canadian study have recommended.
Potent statins were found to raise the diabetes risk by 22% compared with weaker drugs in the population study of people over the age of 66.
Atorvastatin was linked to one extra case of diabetes for every 160 patients treated, the researchers said.
However, the study published in the British Medical Journal said the benefits still outweigh the risks and should still be prescribed to reduce cholesterol levels.
The team of researchers, from hospitals in Toronto, carried out their study following controversy surrounding the risk of diabetes associated with different statins.
They compared the incidence of type 2 diabetes between people taking different strengths of the drug and found that patients treated with atorvastatin, rosuvastatin or simvastatin were at increased risk of new onset diabetes compared with those treated with pravastatin.
They said clinicians should consider this risk when they are contemplating statin treatment for individual patients.
“Preferential use of pravastatin… might be warranted,” they added.
Over the 14 year study period, the researchers identified 471,250 patients with no history of diabetes who were newly treated with a statin.
All analyses in the study used patients treated with pravastatin as the reference comparison group, because pravastatin has been shown to have favorable effects on incident diabetes in animal models and clinical trials.
Compared with pravastatin, the researchers found an increased risk of incident diabetes with atorvastatin, rosuvastatin and simvastatin. There was no significantly increased risk among people who received fluvastatin or lovastatin.
The absolute risk for incident diabetes was about 31 and 34 events per 1,000 people per year for atorvastatin and rosuvastatin, respectively. There was a slightly lower absolute risk with simvastatin – 26 outcomes per 1000 person years – compared with pravastatin – 23 outcomes per 1000 person years.
The authors stated: “Our findings were consistent regardless of whether statins were used for primary or secondary prevention of cardiovascular disease.”
Maureen Talbot, senior cardiac nurse at the British Heart Foundation, said: “Statins are taken safely by millions in the UK and protect those at high risk of developing coronary heart disease.
“Although this study suggests an increased risk of older people developing diabetes when taking certain statins, other risk factors like being overweight, family history and ethnicity may have played their part,” she added.