Against a background of concern about statins increasing the risk of diabetes, a new study has worrying findings for older Australian women.
It showed those who take these anti-cholesterol drugs have a 33 to 50 per cent increased chance of developing diabetes, depending on the dose.
The authors say the "dose effect" is most concerning and these women should not be exposed to high doses.
Lead author, Dr Mark Jones of the University of Queensland's School of Public Health, says over the 10 years of the study most of the women progressed to higher doses of statins.
He suggests older women on these popular drugs should be carefully and regularly monitored for increased blood glucose to ensure early detection and appropriate management of diabetes.
While the increase in risk seems high and is a worry, it is relative risk not an absolute risk. The actual numbers are small.
Decade of study
The study involved 8400 women. At the start none had diabetes but half took statins. Ten years later about 5 per cent of all the women had been diagnosed with diabetes. While the risk for those on statins was close to 6 per cent, for those not on the drugs it was below 5 per cent.
Statins have been in wide use for more than 25 years.
In 2012, the US Food and Drug Administration advised doctors and patients that their use may increase the risk of developing type 2 Diabetes.
To date, most clinical studies suggested people who take statins are at an average 10 per cent increased relative risk of diabetes.
The new study published in the journal Drugs and Aging, drew its data from women who were regularly surveyed as part of the Women's Health Australia study.
It shows that in their late 70s and 80s, about 50 per cent of women were on statins.
"Statins are highly prescribed in this age group but there are very few clinical trials looking at their effects on older women," Dr Jones says.
"The vast majority of research is on 40- to 70-year-old men."
Age key factor
The study shows women over 75 on statins faced an average increased risk of 33 per cent of developing diabetes.
Dr Jones says the result may be explained by the fact that women are more likely to develop diabetes and that age is a risk factor. That the study was long and went deep into old age, were probably factors too.
He was particularly interested in statins because both his parents stopped taking them in their 70s because of side effects such as muscle and memory issues.
He believes older women and their doctors should be aware of the risks.
