Statins had no overall effect on muscle pain compared with placebo in a randomised trial in people who had previously reported severe symptoms to their GP when taking the drugs.
People taking part in the trial in 50 GP practices were either considering stopping taking their statin or had stopped it in the past three years because of muscle symptoms.
Researchers randomly assigned 200 participants to 20mg daily atorvastatin or placebo for six two-month treatment periods without doctors or patients knowing which they were taking when. At the end of each two months they rated their muscle symptoms on a scale of 0-10.
For the 151 patients included in the final analysis there was no difference in muscle symptom scores between statin and placebo treatment periods or on the effect of muscle symptoms on aspects of daily life.
At the end of the study, two thirds of those who had completed the trial restarted long-term treatment with statins.
As well as assessing effects of drugs at a group level, this approach could be a ‘powerful clinical tool’ for GPs assessing how best to investigate muscle symptoms associated with statins in an individual, they concluded.
The researchers pointed out that while severe rhabdomyolysis was rare, occurring in about 0.2 in 10,000 people treated annually, there had been uncertainty about less severe muscle symptoms – a belief which had been reinforced by observational studies and media reports.
Senior study author Professor Liam Smeeth, professor of clinical epidemiology at the London School of Hygiene and Tropical Medicine and a GP in North London, said it was vital to have accurate data on symptoms people experience while taking statins, so that patients and doctors can make informed treatment choices.
‘Many patients stop taking statins due to less severe symptoms, such as muscle pain or fatigue, exposing them to increased cardiovascular disease risk. However, trials have not been able to show if these symptoms are more common in patients taking statins or placebo,’ he said.
‘Our work should reassure those already taking statins or thinking about taking statins.
‘These drugs prevent heart attacks and save lives. In very rare cases they can cause muscle pain, but the vast majority of people will not be affected.’
Professor Tony Avery, professor of primary health care at the University of Nottingham, said it was ‘always a pity’ when patients stopped taking statins due to muscle pains which their doctor is not convinced are drug-related.
He said: ‘In this age group people get aches and pains anyway so it can be very easy to attribute it to the statin. It’s one of those side effects that got into the public psyche.
‘This is a study that will be really helpful when counselling patients. You can say that when they tried people on and off the statins there wasn’t much difference. It’s an extra piece of evidence when you’re having those conversations.’
Professor Martin Marshall, chair of the RCGP said: ‘It’s encouraging to see this research showing that the use of statins does not seem to be associated with the severity or frequency of muscle pain.
‘This builds on evidence to show that statins are safe and effective drugs when used appropriately.
‘We hope this research will go some way to reducing concerns about their use and will feed into an informed shared decision making process between patients and clinicians.’
A previous research paper, published in 2017, concluded that patients on statins are more likely to suffer side effects as a result of the ‘expectation of harm’ rather than the drugs themselves.