The diabetes risk posed by cholesterol-lowering statins is low compared to their beneficial effect in preventing heart attacks, new research suggests.

A team from Glasgow University analysed 13 statin trials from 1994 to 2009. It concluded statin use increased the risk of developing type 2 diabetes by 9%.

But the "absolute risk", it concluded, was low when compared to how the drugs could help "reduce coronary events".

The findings of the study are published in the latest edition of The Lancet.

To date, research had not been able to prove whether or not taking statins raises the risk of developing diabetes.

By going over data from past trials, the team from Glasgow University's cardiovascular research centre aimed to give a more definitive answer.

Its study concluded that treating 255 people with statins over four years would result in one extra case of diabetes.

Closely monitored

However, without statin treatment five of these people would probably have a heart attack. Overall, the study said, the benefits outweigh the risks.

Writing in the Lancet, Professor Naveed Satar and Dr David Preiss said that older people were particularly prone to developing diabetes and should be monitored more closely.

They concluded: "In view of the overwhelming benefit of statins for reduction of cardiovascular events, the small absolute risk for development of diabetes is outweighed by cardiovascular benefit in the short and medium term in individuals for whom statin therapy is recommended.

"We therefore suggest that clinical practice for statin therapy does not need to change for patients with moderate or high cardiovascular risk or existing cardiovascular disease.

"However, the potentially raised diabetes risk should be taken into account if statin therapy is considered for patients at low cardiovascular risk or patient groups in which cardiovascular benefit has not been proven."