Prognostic implications of obstructive sleep apnea in patients with unstable angina stratified by remnant cholesterol and triglyceride: a prospective cohort study

Abstract

Background

The prognostic significance of obstructive sleep apnea (OSA) in patients with unstable angina (UA) based on remnant cholesterol (RC) or triglyceride (TG) levels remains unclear. This study aims to evaluate the effects of the interaction between RC, TG, and OSA on cardiovascular outcomes in UA patients.

Methods

In this prospective cohort study, OSA was diagnosed when apnea-hypopnea index of ≥ 15 events/h. Patients with high RC (HRC, n = 370) or high TG (HTG, n = 362) included RC or TG in the highest tertile, and those in the middle and lowest tertiles were defined as normal RC (NRC, n = 736) or normal TG (NTG, n = 744). The primary endpoint was major adverse cardiovascular and cerebrovascular events (MACCE), including cardiovascular death, myocardial infarction, ischemia stroke, ischemia-driven revascularization, or hospitalization for UA.

Results

A total of 1,106 eligible UA patients were enrolled, among which 560 (50.6%) had OSA. RC and TG levels were increased in OSA patients, but there was no difference in the prevalence of OSA between the NRC and HRC or NTG and HTG groups. During a median follow-up of 1.9 (1.1, 3.0) years, OSA was associated with an increased risk of MACCE occurrence compared to non-OSA in UA patients with HRC (adjusted HR 2.06; 95% CI 1.20–3.51, P = 0.008), but not in those with NRC (adjusted HR 1.21; 95% CI 0.84–1.75, P = 0.297). The incremental risk in HRC was attributable to higher rates of hospitalization for UA and ischemia-driven revascularization. Results for HTG and NTG were similar.

Conclusion

OSA was associated with a worse prognosis in UA patients with HRC or HTG, emphasizing the necessity of identifying OSA presence in this population.

Trial registration

Clinicaltrials.gov; No: NCT03362385.