Emerson Ferreira Martins1, Denis Martinez2, Fernando A Boeira Sabino da Silva3, Lauren Sezerá4, Rodrigo da Rosa de Camargo5, Cintia Zappe Fiori1, Flávio Danni Fuchs6, Ruy Silveira Moraes5. 1. Graduate Program in Cardiology, School of Medicine, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, Brazil; Cardiology Division, Hospital de Clínicas de Porto Alegre (HCPA), Porto Alegre, RS, Brazil. 2. Graduate Program in Cardiology, School of Medicine, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, Brazil; Graduate Program in Medical Sciences, (UFRGS), Brazil; Cardiology Division, Hospital de Clínicas de Porto Alegre (HCPA), Porto Alegre, RS, Brazil; Department of Medicine, School of Medicine, UFRGS, Porto Alegre, RS, Brazil. Electronic address: dm@ufrgs.br. 3. Department of Statistics, UFRGS, Porto Alegre, RS, Brazil. 4. Cardiology Division, Hospital de Clínicas de Porto Alegre (HCPA), Porto Alegre, RS, Brazil. 5. Cardiology Division, Hospital de Clínicas de Porto Alegre (HCPA), Porto Alegre, RS, Brazil; Department of Medicine, School of Medicine, UFRGS, Porto Alegre, RS, Brazil. 6. Graduate Program in Cardiology, School of Medicine, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, Brazil; Cardiology Division, Hospital de Clínicas de Porto Alegre (HCPA), Porto Alegre, RS, Brazil; Department of Medicine, School of Medicine, UFRGS, Porto Alegre, RS, Brazil.
Abstract
BACKGROUND: Obstructive sleep apnea (OSA) patients who suffer sudden cardiac death die predominantly during the night. We aimed to investigate whether all cardiovascular-related deaths display the same night-time peak as sudden cardiac death. METHODS: Data from a large cohort of adults who underwent full-night polysomnography between 1985 and 2015 in a university-affiliated sleep clinic were analyzed. Time and cause of death of these patients and of persons from the general population were identified in death certificates from the State Health Secretariat. The day-night pattern of cardiovascular death was compared among groups of non-OSA, OSA (apnea-hypopnea index, AHI ≥5), CPAP users, and persons from the general population. RESULTS: Among 619 certificates, 160 cardiovascular-related deaths were identified. The time of death of the 142 persons with OSA was uniformly distributed over 24 h, with neither an identifiable peak nor a circadian pattern (Rayleigh test; P = 0.8); the same flat distribution was seen in those with purported CPAP use (n = 49). Non-OSA individuals presented a morning peak and a night nadir of deaths, clearer when analyzed in eight-hour intervals. The same pattern was observed in 92 836 certificates from the State general population, with cardiovascular deaths showing the expected morning peak, night nadir, and a significant circadian pattern (Rayleigh test; P < 0.001). CONCLUSIONS: In OSA patients, the distribution of cardiovascular-related deaths throughout the 24-h period is virtually flat, in contrast with the described nighttime peak of sudden cardiac death. OSA-related phenomena during nighttime might be blunting the mechanisms, arrhythmic or not, behind the morning peak of cardiovascular-related deaths.
BACKGROUND: Obstructive sleep apnea (OSA) patients who suffer sudden cardiac death die predominantly during the night. We aimed to investigate whether all cardiovascular-related deaths display the same night-time peak as sudden cardiac death. METHODS: Data from a large cohort of adults who underwent full-night polysomnography between 1985 and 2015 in a university-affiliated sleep clinic were analyzed. Time and cause of death of these patients and of persons from the general population were identified in death certificates from the State Health Secretariat. The day-night pattern of cardiovascular death was compared among groups of non-OSA, OSA (apnea-hypopnea index, AHI ≥5), CPAP users, and persons from the general population. RESULTS: Among 619 certificates, 160 cardiovascular-related deaths were identified. The time of death of the 142 persons with OSA was uniformly distributed over 24 h, with neither an identifiable peak nor a circadian pattern (Rayleigh test; P = 0.8); the same flat distribution was seen in those with purported CPAP use (n = 49). Non-OSA individuals presented a morning peak and a night nadir of deaths, clearer when analyzed in eight-hour intervals. The same pattern was observed in 92 836 certificates from the State general population, with cardiovascular deaths showing the expected morning peak, night nadir, and a significant circadian pattern (Rayleigh test; P < 0.001). CONCLUSIONS: In OSA patients, the distribution of cardiovascular-related deaths throughout the 24-h period is virtually flat, in contrast with the described nighttime peak of sudden cardiac death. OSA-related phenomena during nighttime might be blunting the mechanisms, arrhythmic or not, behind the morning peak of cardiovascular-related deaths.
Authors: Matthew P Butler; Saurabh S Thosar; Carolina Smales; Pamela N DeYoung; Huijuan Wu; Mohammad V Hussain; Miki Morimoto; Kun Hu; Frank A J L Scheer; Steven A Shea Journal: Chronobiol Int Date: 2020-03-20 Impact factor: 2.877