Statin-related muscle disease in clinical practice; a descriptive study in a group of Sri Lankan patients

Abstract

AttachedIntroduction Statin-related muscle disease (SRMD) which affects quality of life and exercise tolerance is often overlooked. Objectives Objective of this study was to describe prevalence and associated factors of SRMD in clinical practice. It has not been studied in Sri Lanka previously. Method Consecutive patients receiving statin therapy at outpatient clinics of a tertiary-care hospital < who were screened for a clinical trial on ' SRMD were studied. Details were recorded using an interviewer administered ! questionnaire. SRMD was defined as presence of muscle symptoms started after initiation of j statins with no alternative cause detected after clinical assessment, and investigations. Myositis was defined as SRMD with elevated creatine phosphokinase. Data were analysed with SPSS version-19.0 Results 375 patients were studied; 63.7% were females; mean age was 63.2±10years. All were on atorvastatin (dose: mean 16.5mg, range 5-40mg; duration: mean 64.2 months, range 1-241 months). Prevalence of SRMD and myositis was 14.7% (55/375) and 2.1% (8/375), respectively. Most frequent symptoms were cramps (81.8%) and myalgia (43.6%). Mean severity score (Visual Analogue Scale) was 5.4 (range: 2-10). Severity was more ih women (6.3 Vs 4.2; p=0.015). Mean duration of therapy before onset of SRMD was 53.8months (median: 48months range: 1- 172months). 27.3% were on co-medications potentially affecting atorvastatin metabolism. No association was found between SRMD and age, gender, atorvastatin dose, treatment duration or co-medications. Conclusions Prevalence of statin-related muscle disease was high and of moderate severity in the study population. It is compatible with reports from other countries. No factors associated with SRMD were identified in this population.