Comparative Effectiveness and Safety of Atorvastatin Versus Rosuvastatin

BACKGROUND: Rosuvastatin and atorvastatin are the most widely prescribed moderate- to high-intensity statins. However, evidence on their efficacy and safety during actual use is limited. OBJECTIVE: To compare the real-world effectiveness and safety of rosuvastatin and atorvastatin. DESIGN: Active comparator cohort study using target trial emulation. SETTING: The China Renal Data System (CRDS) and UK Biobank (UKB) databases. PARTICIPANTS: Adults newly prescribed rosuvastatin or atorvastatin. MEASUREMENTS: The primary outcome was all-cause mortality. Cox proportional hazards regressions were used after 1:1 multilevel propensity score matching. RESULTS: Among the 285 680 eligible participants in both databases, 6-year all-cause mortality was lower for rosuvastatin than for atorvastatin (2.57 vs. 2.83 per 100 person-years in the CRDS database and 0.66 vs. 0.90 per 100 person-years in the UKB database), with differences in cumulative incidence of -1.03% (95% CI, -1.44% to -0.46%) in the CRDS database and -1.38% (CI, -2.50% to -0.21%) in the UKB database. For secondary outcomes in both databases, rosuvastatin conferred lower risks for major adverse cardiovascular events and major adverse liver outcomes. In the UKB database, the risk for development of type 2 diabetes mellitus was higher with rosuvastatin, and the 2 medications carried similar risks for development of chronic kidney disease and other statin-related adverse effects. LIMITATION: Possible residual confounding. CONCLUSION: This study found differences in risks for some important outcomes associated with rosuvastatin and atorvastatin. The differences were relatively small, and many did not meet traditional standards for statistical significance. Further research is needed to understand whether these findings can be used with confidence in clinical practice. PRIMARY FUNDING SOURCE: National Key R&D Program of China and National Natural Science Foundation of China.