Purpose: Sleep disorders affect the proper function of cardiovascular system via several pathophysiological paths that are still poorly investigated. The previous years there were conflicting data about the impact of sleep deprivation or excess on morbidity and mortality from cardiovascular disease.
Aim: To investigate possible relationship between duration of daily sleep and morbidity or mortality from cardiovascular disease.
Methods: Systematic research through electronic databases was performed to find prospective studies that were published within last 5 years and population of interest was adults without known cardiovascular disease. The exposure was duration of daily sleep and the outcome was the morbidity and mortality from stroke, coronary heart disease or cardiovascular disease.
Results: 11 publications were included in this meta-analysis. Two groups; short (<6h) and long (>9h) daily sleep duration were compared to the reference group (6–9h). For the first comparison 10 out of 11 studies were included and 7 out of 11 for the second one. Both short (RR=1.11, 95% CI 1.03–1.19, P=0.007) and long (RR=1.32, 95% CI 1.22–1.43, P<0.001) sleep duration were associated with greater risk of cardiovascular disease or cardiovascular death. Neither publication bias, nor significant heterogeneity was observed. Medium scale heterogeneity was found in analysis of short sleep duration (Q=17.05, p=0.048, I2=47.2%), but after heterogeneity analysis proved to be non-influencial to final results.
Conclusion: Any deflection from normal daily sleep duration is statistically related to greater risk of cardiovascular disease and cardiovascular death.