Short sleepers at higher risk of myocardial infarction
Short sleep duration is associated with an increased risk of myocardial infarction (MI), according to prospective observational and Mendelian randomization (MR) analyses.
Sleeping for <6 h was associated with a 20-percent higher multivariable-adjusted risk of incident MI (hazard ratio [HR], 1.20, 95 percent CI, 1.07–1.33) compared with sleeping 6–9 h/night, while long sleep duration (>9 h) correlated with 34-percent higher risk (HR, 1.34, 1.13–1.58). These associations were independent of other sleep traits.
On the other hand, MI risk decreased with healthy sleep duration even among individuals with high genetic liability (HR, 0.82, 0.68–0.998). Moreover, MR consistently showed a causal effect of short sleep duration on MI in CARDIoGRAMplusC4D (HR, 1.19, 1.09–1.29) and in UK Biobank (HR, 1.21, 1.08–1.37).
In this study, the authors examined the associations between sleep duration and incident MI, accounting for joint effects with other sleep traits and genetic risk of coronary artery disease, and assessed causality using MR.
Multivariable-adjusted HRs for MI (5,129 incident cases) were estimated across habitual self-reported short and long sleep duration in 461,347 UK Biobank participants free of relevant cardiovascular disease. Joint effects with sleep disturbance traits and a coronary artery disease genetic risk score were also investigated.
Two-sample MR was performed for short (24 single nucleotide polymorphisms) and continuous (71 single nucleotide polymorphisms) sleep duration with MI (n=43,676 cases/128,199 controls). Results were replicated in the UK Biobank (n=12,111/325421).
“Investigation of sleep extension to prevent MI may be warranted,” the authors said.