Older adult patients with frailty are rarely involved in rehabilitation programs after myocardial infarction. Our aim was to investigate the benefits of exercise intervention in these patients.

A total of 150 survivors after acute myocardial infarction, ≥70 years and with pre-frailty or frailty (Fried scale ≥1 points), were randomized to control (n = 77) or intervention (n = 73) groups. The intervention consisted of a 3-month exercise program, under physiotherapist supervision, followed by an independent home-based program. The main outcome was frailty (Fried scale) at 3 months and 1 year. Secondary endpoints were clinical events (mortality or any readmission) at 1 year.

Mean age was 80 years (range = 70-96). In the intervention group, 44 (60%) out of 73 patients participated in the program and 23 (32%) completed it. Overall, there was a decrease in the Fried score in the intervention group at 3 months, with no effect at 1 year. However, in the intention-to-treat analysis, such change did not achieve statistical significance (P = 0.110). Only treatment comparisons made among the subgroups that participated in (P = 0.033) and completed (P = 0.018) the program achieved statistical significance. There were no differences in clinical events. Worse Fried score trajectory along follow-up increased mortality risk (hazard ratio [HR] = 2.38, 95% confidence interval [CI] 1.24-4.55, P = 0.009)

Recruitment and retention for a physical program in older adult patients with frailty after myocardial infarction was challenging. Frailty status improved in the subgroup that participated in the program, although this benefit was attenuated after shifting to a home-based program. A better frailty trajectory might influence midterm prognosis. (ClinicalTrials.govNCT02715453).