Statin use is associated with less ST-elevation versus non-ST-elevation myocardial infarction in a nationwide study

Background and aims: Statin therapy reduces myocardial infarction rate but whether it is associated with a shift of ST-elevation myocardial infarction (STEMI) towards non-ST-elevation myocardial infarction (non-STEMI) remains unknown. Thus, we tested the hypothesis that statin use is associated with less STEMI relative to non-STEMI in first-time myocardial infarction. Methods: In a nationwide study, including 66,896 patients with first-time myocardial infarction between 2010 and 2021, we obtained multivariable risk estimates for STEMI versus non-STEMI according to any statin use, cumulated statin use, and daily statin dose. Furthermore, we obtained hazard ratios for 60-day mortality (5545 deaths) following myocardial infarction according to type of infarction. Results: Odds ratios for STEMI versus non-STEMI were 0.81 (95 % CI:0.77–0.85) and 1.07 (1.01–1.13) in current and previous statin users compared to never statin users. Cumulated statin exposure yielded odds ratios of 0.96 (0.87–1.07) for <2 statin-years, 0.87 (0.79–0.95) for 2–4.9 statin-years, 0.80 (0.74–0.87) for 5–10 statin-years, and 0.75 (0.70–0.80) for >10 statin-years compared to never users. Corresponding odds ratios for statin dose intensity were 0.89 (0.84–0.95) for low-intensity, 0.77 (0.73–0.82) for moderate-intensity, and 0.70 (0.63–0.77) for high-intensity. Results were similar in multiple sensitivity analyses and using a cohort design. The hazard ratio for 60-day mortality after first-time STEMI versus non-STEMI was 2.24 (2.13–2.37). Conclusions: In this nationwide study, prior statin use is associated with less STEMI relative to non-STEMI in a dose dependent manner. This indicates that statin therapy, in addition to reducing myocardial infarction event rates, also result in a less severe presentation of myocardial infarctions.