In 2019, we conducted an intervention study, MUSE. The purpose of the study was to investigate the effect of statins on muscle symptom intensity in patients with self-perceived statin muscle side-effects. We will also investigate whether statin metabolites in blood may be used to predict true statin-dependent muscle side effects.
The hospital records of almost 1000 patients hospitalized in Drammen and Vestfold with an acute myocardial infarction in 2016-2019 were screened through a telephone interview. Out of this group, 77 patients who reported statin-related muscle side-effects were randomized to 7 weeks double-blinded treatment with atorvastatin 40 mg / day and 7 weeks treatment with an identical placebo tablet, in random order. Patients recorded muscle symptoms weekly in a diary throughout the study. At the beginning of the trial and following each 7-week treatment cycle, blood samples were collected for analysis, including testing for statin metabolites, cholesterol levels, inflammatory markers, and genes related to statin metabolism. In addition, patients completed a questionnaire addressing topics such as cholesterol treatment adherence, psychological factors, and details regarding the location and characteristics of their muscle symptoms.
In 2020, a follow-up intervention study of the MUSE population was conducted with the aim of gaining additional knowledge about the effects of statins on muscle tissue and to identify objective diagnostic biomarkers that could detect statin-related muscle side effects . Fifteen patients with proven atorvastatin-dependend muscle side effects and 15 patients without such side effects from the previous MUSE tudy were selected to undego a new 7-week treatment with atorvastatin 40 mg / day followed by a 7-weeks without statins. Muscle symptoms were recorded weekly in a diary, and blood and muscle tissue samples were collected for analyses of statin metabolites and biomarkers (fats, proteins, genetic material) that may be associated with muscle toxicity. Additionally, we examined the muscle samples under a microscope to assess any structural changes in the muscle cells or surrounding tissue.