Obstructive sleep apnea increases recurrent cardiovascular event risk in younger but not older patients with acute coronary syndrome: a prospective cohort study.

BACKGROUND

Obstructive sleep apnea (OSA) and age are strongly associated with recurrent events following acute coronary syndrome (ACS), but their interaction is unclear. This study was designed to evaluate the age-dependent impact of OSA on long-term outcomes in patients with ACS.

METHODS

In this prospective, large-scale cohort study, 2160 patients admitted for ACS were recruited for sleep monitoring after clinical stabilization. OSA was diagnosed when the apnea-hypopnea index was ≥15 events/h. The primary endpoint was major adverse cardiovascular event (MACE), which included cardiovascular death, myocardial infarction, stroke and ischemia-driven revascularization.

FINDINGS: Of 1927 eligible patients (average age: 56.4 ± 10.5 years; 298 [15.5%] women), 52.6% had OSA. The prevalence of OSA did not increase with age. During 2.9 years (interquartile range: 1.5 years to 3.6 years) of follow-up, the risk increase effect of OSA versus non-OSA on MACE gradually decreased with age and was no longer pronounced in the subpopulations age 58 years and older. In younger patients with ACS (adjusted HR, 1.68; 95% CI, 1.12-2.52) but not in older patients with ACS ≥58 years (adjusted HR, 0.98; 95% CI, 0.69-1.40), OSA was associated with a 1.68-fold increased risk of MACEs versus non-OSA. Subgroup and sensitivity analyses were consistent with main results.

INTERPRETATION: OSA was associated with an increased risk of subsequent MACEs among younger patients with ACS. Aggressive screening and diagnosis for OSA may be recommended for younger patients with ACS. Further studies are needed to verify these findings.

FUNDINGS: National Natural Science Foundation of China (grant numbers 82370338, 82270258), Noncommunicable Chronic Diseases-National Science and Technology Major Project (2024ZD0529100), National High Level Hospital Clinical Research Funding (BJ-2024-226, BJ-2025-112, BJ-2025-325), Beijing Natural Science Foundation [24JL001].

TRIAL REGISTRATION: Clinicaltrials.gov, no. NCT03362385.