Introduction: Switching from any statin to another non-equipotent lipid lowering treatment (LLT) may cause a low-density lipoprotein cholesterol increase and has been associated with a higher probability of negative cardiovascular outcomes. The aim of the study was to assess the impact of switching from rosuvastatin to any other LLT on clinical outcomes in primary care.
Methods: This was a retrospective analysis based on data from IMS Health Longitudinal Patient Database, which is a general practice database including information of more than 1.0 million patients representative of the Italian population by age, and medical conditions. Patients that started on rosuvastatin (10-40 mg/day) between January 2011 and December 2013 were considered. The date of the first prescription was defined as the index date (ID). The observation period lasted from the ID to September 2015 or until LLT discontinuation, or the occurrence of an acute myocardial infarction (AMI), or death.
Results: The primary end point of the study was the occurrence of an AMI during the observation period. The final study population included 10,368 patients. During the observation period, 2452 (23.6%) patients were switched from rosuvastatin to another LLT. The majority of patients (55.6%) were switched to atorvastatin, followed by simvastatin (24.9%), simvastatin/ezetimibe combination (10.0%) and other statins (9.5%). Female gender (HR, hazard ratio, 1.10, 95% CI, confidence interval, 1.02-1.19, p = 0.04) and the presence of chronic kidney disease (HR 1.47, 95% CI 1.16-1.86, p = 0.05) were associated with a higher probability of switch. During the observation period, 113 patients experienced an AMI (incidence of 6.7 AMI/1000 patient-years). Multivariate analysis with Cox proportional hazards method, including switching as a time-dependent covariate, demonstrated that changing from rosuvastatin to another LLT was an independent predictor of AMI (HR 2.2, 95% CI 1.4-3.5, p = 0.001).
Conclusion: We conclude that switching from rosuvastatin to another non-equipotent LLT may impart an increased risk of AMI and should be avoided.
Funding: AstraZeneca SpA.
Keywords: AMI; Acute myocardial infarction; Cox; Endocrinology; Hazard; Incidence; Lipid lowering; Rosuvastatin; Statin; Switch.