Whether a conservative strategy of medical therapy alone or a strategy of medical therapy plus invasive treatment is more beneficial in older adults with non-ST-segment elevation myocardial infarction (NSTEMI) remains unclear.

We conducted a prospective, multicenter, randomized trial involving patients 75 years of age or older with NSTEMI at 48 sites in the United Kingdom. The patients were assigned in a 1:1 ratio to a conservative strategy of the best available medical therapy or an invasive strategy of coronary angiography and revascularization plus the best available medical therapy. Patients who were frail or had a high burden of coexisting conditions were eligible. The primary outcome was a composite of death from cardiovascular causes (cardiovascular death) or nonfatal myocardial infarction assessed in a time-to-event analysis.

A total of 1518 patients underwent randomization; 753 patients were assigned to the invasive-strategy group and 765 to the conservative-strategy group. The mean age of the patients was 82 years, 45% were women, and 32% were frail. A primary-outcome event occurred in 193 patients (25.6%) in the invasive-strategy group and 201 patients (26.3%) in the conservative-strategy group (hazard ratio, 0.94; 95% confidence interval [CI], 0.77 to 1.14; P = 0.53) over a median follow-up of 4.1 years. Cardiovascular death occurred in 15.8% of the patients in the invasive-strategy group and 14.2% of the patients in the conservative-strategy group (hazard ratio, 1.11; 95% CI, 0.86 to 1.44). Nonfatal myocardial infarction occurred in 11.7% in the invasive-strategy group and 15.0% in the conservative-strategy group (hazard ratio, 0.75; 95% CI, 0.57 to 0.99). Procedural complications occurred in less than 1% of the patients.

In older adults with NSTEMI, an invasive strategy did not result in a significantly lower risk of cardiovascular death or nonfatal myocardial infarction (the composite primary outcome) than a conservative strategy over a median follow-up of 4.1 years. (Funded by the British Heart Foundation; BHF SENIOR-RITA ISRCTN Registry number, ISRCTN11343602.).