BACKGROUND: Older people are underrepresented in randomized trials. The association between lipid-lowering therapy (LLT) and its intensity after acute myocardial infarction and long-term mortality in this population deserves to be assessed. METHODS: The FAST-MI (French Registry of Acute ST-Elevation or Non-ST-Elevation Myocardial Infarction) program consists of nationwide French surveys including all patients admitted for acute myocardial infarction ≤48 hours from onset over a 1- to 2-month period in 2005, 2010, and 2015, with long-term follow-up. Numerous data were collected and a centralized 10-year follow-up was organized. The present analysis focused on the association between prescription of LLT (atorvastatin ≥40 mg or equivalent, or any combination of statin and ezetimibe) and 5-year mortality in patients aged ≥80 years discharged alive. Cox multivariable analysis and propensity score matching were used to adjust for baseline differences. RESULTS: Among the 2258 patients aged ≥80 years (mean age, 85±4 years; 51% women; 39% ST-segment elevation myocardial infarction; 58% with percutaneous coronary intervention), 415 were discharged without LLT (18%), 866 with conventional doses (38%), and 977 with high-dose LLT (43%). Five-year survival was 36%, 47.5%, and 58%, respectively. Compared with patients without LLT, high-dose LLT was significantly associated with lower 5-year mortality (adjusted hazard ratio, 0.78 [95% CI, 0.66-0.92]), whereas conventional-intensity LLT was not (adjusted hazard ratio, 0.93 [95% CI, 0.80-1.09]). In propensity score-matched cohorts (n=278 receiving high-intensity LLT and n=278 receiving no statins), 5-year survival was 52% with high-intensity LLT at discharge and 42% without statins (hazard ratio, 0.78 [95% CI, 0.62-0.98]). CONCLUSIONS: In these observational cohorts, high-intensity LLT at discharge after acute myocardial infarction was associated with reduced all-cause mortality at 5 years in an older adult population. These results suggest that high-intensity LLT should not be denied to patients on the basis of old age. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifiers: NCT00673036, NCT01237418, and NCT02566200.