Anabolic–Androgenic Steroid Use, All-Cause Mortality, and Major Cardiovascular Outcomes: A Systematic Review and Meta-Analysis

Background/Objectives: Non-medical anabolic-androgenic steroid (AAS) use has been associated with adverse cardiac remodelling, but the magnitude of excess all-cause mortality and the cardiac phenotype of former users remain incompletely defined. Methods: We systematically reviewed studies reporting mortality, major cardiovascular outcomes, or cardiac function after cessation in AAS-exposed individuals. All-cause mortality was pooled from comparative cohorts with individually ascertained exposure using random-effects models; global longitudinal strain (GLS) and left ventricular ejection fraction in former users were pooled as mean differences. Risk of bias was assessed with ROBINS-E and certainty with GRADE. Results: Fifteen primary reports were included. Across three cohorts, AAS exposure was associated with higher all-cause mortality (risk ratio 2.57, 95% CI 1.98–3.33; I2 = 0%; 95% prediction interval 0.47–13.87), with consistent sensitivity analyses. In a single large matched cohort, adjusted hazard ratios for cardiovascular outcomes ranged from 2.26 to 8.90, highest for cardiomyopathy. Former users had worse GLS than AAS-naïve controls (3 studies; mean difference +0.90 percentage points, 95% CI +0.13 to +1.66), whereas the pooled ejection-fraction estimate was exploratory and highly heterogeneous. Conclusions: AAS exposure was associated with higher all-cause mortality in three observational cohorts, but residual confounding, differing follow-up, and the small evidence base preclude causal inference. Cardiovascular associations from a single cohort require independent replication, and evidence on residual myocardial dysfunction in former users is of very low certainty.