Prevalence of Potential Statin-Drug Interactions in Dyslipidemic Patients at Srinagarind Hospital

Abstract

Background and Objective: Statin-drug interaction is one of the major factors associated with musculoskeletal adverse effect and may lead to statin intolerance and discontinuation.  This study aim to investigate the prevalence and clinically significant level of potential statin-drug interactions in prescriptions for dyslipidemia patients at the Srinagarind Hospital, Khon Kaen University. 

Methods: Data of outpatients who received statins, including simvastatin (SVS) (n=400) and atorvastatin (ATV) (n=500) during January to December 2012 were retrieved and randomly selected from hospital electronic database and patient medical records. The potential interacting drug lists and the clinically significant level were defined according to Drug Interaction Fact 2011 reference. 

Results: Overall, the potential statin-drug interactions were found in 145 patients (16.1%).  Of 3379 prescriptions screened, we found 496 prescriptions (14.7%; SVS 15.3%, ATV 14.0%) with 539 pairs of potential statin-drug interactions.   Of these, most frequent drug interaction was diltiazem (21.9%), colchicine (21.5%), and gemfibrozil (13.4%).  The potential statin-drug interaction found in the level of probable was 33.4% ( SVS 38.4%, ATV 28.1%), suspected was 37.5% (SVS 28.3%, ATV 47.1%) and possible was 29.1% (SVS 33.3%, ATV 24.4%). We found potential statin-drug interaction with clinically significant level 1 of 36.0%, level 2 of 34.5%  and level 4 of 29.1%. 

Conclusion: Potential statin-drug interactions were found in drug prescriptions of dyslipidemic outpatients at Srinagarind Hospital.  The levels of documentation were mostly in suspected and probable levels, and in high potential for clinical significance.  Data suggested that an increase in awareness of prescription of statin over drug interactions and monitoring for the adverse effects may improve the therapeutic outcome.