. 2022 Aug 11;9:930000. doi: 10.3389/fcvm.2022.930000

TABLE 1.

Sleep duration and cardiovascular diseases in observational meta-analyses.

References	Outcome	n	Exposure	Main results	Summary
Wang et al. (33) (AMSTAR = 11)	CHD	17	Short and long sleep duration	RR _{reduction of 1 h per day} = 1.11; 95% CI: 1.05–1.16 RR _{increment of 1 h per day} = 1.07; 95% CI: 1.00–1.15 compared with 7 h sleep duration per day	High-quality meta-analyses showed that both short and long sleep duration were significantly associated with increased risk of CHD, with high heterogeneity. Subgroup and sensitivity analysis further confirmed the above views.
He et al. (38) (AMSTAR = 9)	Stroke	16	Short and long sleep duration	Took 7 h of sleep as the reference: RRs (95% CI): 4 h: 1.17 (0.99–1.38); 5 h: 1.17 (1.00–1.37); 6 h: 1.10 (1.00–1.21); 8 h: 1.17 (1.07–1.28); 9 h: 1.45 (1.23–1.70); 10 h: 1.64 (1.4–1.92)	Equitable quality reviews showed that long sleep duration significantly increased the risk of overall stroke and fatal stroke in a linear manner.
Liu et al. (41) (AMSTAR = 8)	Mortality	40	Short and long sleep duration	Took 7 h of sleep as the reference: RRs (95% CI): 4 h: 1.05 (1.02–1.07); 5 h: 1.06 (1.03–1.09); 6 h: 1.04 (1.03–1.06); 8 h: 1.03 (1.02–1.05); 9 h: 1.13 (1.10–1.16); 10 h: 1.25 (1.22–1.29); 11 h: 1.38 (1.33–1.44)	Equitable quality reviews showed that both short and long sleep duration increased the risk of all-cause mortality, long sleep duration associated with a higher risk than short sleep duration, and the association was stronger in women. Sensitivity analysis further verified the reliability of the conclusion.
Pienaar et al. (42) (AMSTAR = 11)	Mortality	5	Short and long sleep duration	Short sleep duration: ACM: RR = 1.16; 95% CI: 1.11–1.22; I² = 45.8% CVDM: RR = 1.26; 95% CI: 1.12–1.41; I² = 45.8% Long sleep duration: ACM: RR = 1.18; 95% CI: 1.12–1.23; I² = 86.0% CVDM: RR = 1.10; 95% CI: 0.95–1.27; I² = 0.0%	High-quality meta-analyses showed that short sleep duration was significantly associated with both all-cause mortality and cardiovascular mortality, heterogeneity was not significant. The study focused on employed people under the age of 65 living in cities, highlighting the need for adequate sleep in the urban workforce.

AMSTAR, assessment of multiple systematic reviews; n, number of comparisons; CHD, coronary heart disease; RR, risk ratio; CI, confidence interval; ACM, all-cause mortality; CVDM, cardiovascular disease mortality.