Day–night pattern of acute ST-segment elevation myocardial infarction onset in patients with obstructive sleep apnea

Obstructive sleep apnea (OSA) is associated with acute nocturnal hemodynamic and neurohormonal abnormalities that may increase the risk of coronary events, especially during the nighttime. This study sought to investigate the day-night pattern of acute ST-segment elevation myocardial infarction (STEMI) onset in patients with OSA and its impact on cardiovascular adverse events.We prospectively enrolled 397 patients with STEMI, for which the time of onset of chest pain was clearly identified. All subjects were categorized into non-OSA (n = 280) and OSA (n = 117) groups. The association between STEMI onset time and major adverse cardiovascular and cerebrovascular events (MACCEs) was estimated by Cox proportional hazards regression.STEMI onset occurred from midnight to 5:59 a.m. in 33% of patients with OSA, as compared with 15% in non-OSA patients (P < 0.01). For OSA individuals, the relative risk of STEMI from midnight to 5:59 a.m. was 2.717 (95% CI 1.616-4.568) compared with non-OSA patients. After a median of 2.89 ± 0.78 years follow-up, symptom onset time was found to be significantly associated with risk of MACCEs in patients with OSA, while there was no significant association observed in non-OSA patients. Compared with STEMI presenting during noon to 5:59 p.m., the hazard ratios (HRs) for MACCEs in patients with OSA were 4.683 (95% CI 2.024 to 21.409, P = 0.027) for midnight to 5:59 a.m., and 6.964 (95% CI 1.379 to 35.169, P = 0.019) for 6 p.m. to midnight, whereas the HRs for non-OSA patients were 1.053 (95% CI 0.394 to 2.813, P = 0.917) for midnight to 5:59 a.m., and 0.745 (95% CI 0.278 to 1.995, P = 0.558) for 6 p.m. to midnight.Patients with OSA exhibited a peak incidence of STEMI between midnight and 5:59 a.m., which showed an independent association with cardiovascular adverse events.