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 also wanted to 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. Of these, 77 patients who reported statin 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 reported muscle symptoms weekly in a diary throughout the both treatment periods. At the start of the study and at the end of each 7-weeks treatment period, blood samples were collected for analysis of statin metabolites, lipid profile, inflammatory markers and genetic variants of potential importance for statin metabolism. The patients also completed a questionnaire about cholesterol treatment and adherence, psychological factors and muscle symptom characteristics and location.
In 2020, a follow-up intervention study of the MUSE population was conducted. The overall objective of the follow-up study is to provide new pathophysiologic knowledge of statin effects in muscle tissue and to identify objective diagnostic biomarkers that may predict statin-dependent muscle side effects . In all, patients from the MUSE trial with (13 patients) and without (15 patients) confirmed atorvastatin-dependent muscle side-effects carry out a underwent a 7-weeks treatment period with atorvastatin 40 mg / day followed by a 7-weeks period without statin treatment. Muscle symptoms were reported weekly in a diary throughout both treatment periods and blood samples and muscle tissue were collected for analyses of statin metabolites and other biomarkers (fats, proteins, genetic material) that may be associated with muscle toxicity. We have also evaluated the muscle samples under a microscope to determine if there are changes in the structure of the muscle cells or the surrounding tissue.
In 2021, a randomized controlled trial, OPTI-STATIN, will commence. The purpose of the study is to investigate whether measurements of statins in blood are useful in clinical practice to monitor and personalize treatment in patients with established cardiovascular disease or at increased risk. The study include several sub-projects that focus on pharmacology, health economics, health communication, psychological factors.