AimsSTRONG‐HF examined a high‐intensity care (HIC) strategy of rapid up‐titration of guideline‐directed medical therapy (GDMT) and close follow‐up after acute heart failure (AHF) admission. We assess the role of age on efficacy and safety of HIC.Methods and resultsHospitalized AHF patients, not treated with optimal GDMT were randomized to HIC or usual care. The primary endpoint of 180‐day death or HF readmission occurred equally in older (>65 years, n = 493, 74 ± 5 years) and younger patients (53 ± 11 years, adjusted hazard ratio [aHR] 1.02, 95% confidence interval [CI] 0.73–1.43, p = 0.89). Older patients received slightly lower GDMT to day 21, but same doses at day 90 and 180. The effect of HIC on the primary endpoint was numerically higher in younger (aHR 0.51, 95% CI 0.32–0.82) than older patients (aHR 0.73, 95% CI 0.46–1.15, adjusted interaction p = 0.30), partially related to COVID‐19 deaths. After exclusion of COVID‐19 deaths, the effect of HIC was similar in younger (aHR 0.51, 95% CI 0.32–0.82) and older patients (aHR 0.63, 95% CI 0.32–1.02, adjusted interaction p = 0.56), with no treatment‐by‐age interaction (interaction p = 0.57). HIC induced larger improvements in quality of life to day 90 in younger (EQ‐VAS adjusted‐mean difference 5.51, 95% CI 3.20–7.82) than in older patients (1.77, 95% CI −0.75 to 4.29, interaction p = 0.032). HIC was associated with similar rates of adverse events in older and younger patients.ConclusionHigh‐intensity care after AHF was safe and resulted in a significant reduction of all‐cause death or HF readmission at 180 days across the study age spectrum. Older patients have smaller benefits in terms of quality of life.