Long-term statin use 'increases diabetes risk'
24th October 2017 – People at high risk of type 2 diabetes are more likely to develop the disease if they take statins over a long period of time, according to a study.
Researchers say it is possible that statins, commonly taken to lower cholesterol and reduce the risk of heart disease, may impair production of insulin, the hormone that lowers levels of blood sugar.
However, they say any increase in the risk of diabetes should be weighed against the significant reduction in the risk of heart disease or stroke that comes with taking statins.
Diabetes prevention programme
The study is based on 3,234 people taking part in the US Diabetes Prevention Program Outcomes Study. Participants in the clinical trial are being tracked to see whether modest weight loss or treatment with metformin - a drug to lower blood sugar levels - can reduce or delay type 2 diabetes from developing.
All those taking part were given advice about healthy eating and getting enough exercise. They were then randomly assigned to either an intensive programme for adopting a heather lifestyle, treatment with metformin or a dummy ( placebo) medication.
At the outset, fewer than 4% were taking statins but after 10 years this had increased to around a third in all groups. Simvastatin was taken by 40% of statin users and atorvastatin by 37%.
The study, in the journal BMJ Open Diabetes Research and Care, found that those who took statins had a higher risk of type 2 diabetes, irrespective of which treatment group they had been assigned to.
When all treatment groups were combined, taking a statin was associated with a 36% increased risk of being diagnosed with type 2 diabetes after 10 years, compared to those who had not been prescribed these drugs.
The researchers say they found no link between the potency of the statin used and the risk of diabetes. There was also no link between the reduction in low density lipoprotein – LDL, or the so-called 'bad cholesterol' – and the risk of developing the disease, they say.
The authors point out that they carried out an observational study and therefore are unable to draw firm conclusions about cause and effect.
However, they write that "glucose status should be monitored and healthy lifestyle behaviours reinforced in high risk patients who are prescribed statins for CVD [cardiovascular disease prevention]".
'Discuss any concerns'
Commenting on the findings in an emailed statement, Pav Kalsi, senior clinical advisor at Diabetes UK, says: "Statins can significantly reduce the risk of heart attacks and strokes, so it is important that people who have been prescribed statins continue to take their medication. If they have any concerns about the medication they are taking, then they should discuss this with their doctor.
"There are a number of different factors that can increase a person’s risk of developing type 2 diabetes. To reduce this risk, we recommend that people follow a balanced diet, do regular physical activity, maintain a healthy weight and have regular check-ups with their doctor."