Statins use not associated with any muscle symptoms, finds BMJ Study

UK: There was no effect of atorvastatin 20 mg on muscle symptoms versus placebo in patients who had reported severe muscle symptoms previously when taking statins, finds a recent study in The BMJ. Most people who completed the trial intended to restart statin treatment.

Statins, are a class of lipid-lowering medications, reduce cardiovascular disease events in primary and secondary prevention. Previous research have confirmed the safety of statins. Although with statins use, severe adverse effects are rare, they increase the risk of myopathy which can progress to severe rhabdomyolysis. However, uncertainty persists about less severe muscle symptoms.  

Many people believe that statins frequently cause muscle pain -- a view that has been reinforced by results from media reports and unblinded observational studies. This has led to many people discontinuing treatment that exposes them to increased risk of cardiovascular disease. 

For a patient receiving statin treatment it becomes important to reliably determine whether muscle symptoms are cause by statins. One way to determine this is conducting a blinded n-of-1 trials in individual patients with symptoms during statin treatment. N-of-1 trials are a randomised trial in individual patients that can provide information to help determine the best course of action in an individual. When a number of n-of-1 individuals are combined in an analysis, the result can also be used to assess the overall effect of a treatment.

Emily Herrett, assistant professor, London School of Hygiene and Tropical Medicine, London, UK, hereby, describe the results of StatinWISE (Statin Web-based Investigation of Side Effects), a series of n-of-1 trials comparing treatment periods of statins and placebo in people who had previously reported muscle symptoms when taking statins. The trials were conducted in primary care across 50 sites in the United Kingdom, December 2016 to April 2018.

The aim of the study was to establish the effect of statins on all muscle symptoms and on muscle symptoms that are perceived to be related to statins. It included 200 participants who had recently stopped or were considering stopping treatment with statins because of muscle symptoms.

Participants were randomised to a sequence of six double blinded treatment periods (two months each) of atorvastatin 20 mg daily or placebo.

At the end of each treatment period, participants rated their muscle symptoms on a visual analogue scale (0-10). The primary analysis compared symptom scores in the statin and placebo periods. 

"No overall effect of atorvastatin 20 mg on muscle symptoms compared with placebo was found in participants who had previously reported severe muscle symptoms when taking statins," wrote the authors. "Most people completing the trial intended to restart treatment with statins. N-of-1 trials can assess drug effects at the group level and guide individual treatment."

The study titled, "Statin treatment and muscle symptoms: series of randomised, placebo controlled n-of-1 trials," is published in the journal BMJ. 

DOI: https://www.bmj.com/content/372/bmj.n135