Relationship between daytime napping and cardiovascular disease: A two-sample mendelian randomization study

OBJECTIVE Daytime napping has been reported to have a potential association with an increased risk of cardiovascular diseases (CVDs) in several cohort studies, but the causal effects are unclear. In this study, we aimed to investigate relationship between daytime napping and CVDs, as well as to validate causality in this relationship by Mendelian randomization (MR). METHODS A two -sample MR method was used to evaluate the causal effect of daytime napping on CVDs. The exposure of daytime napping was extracted from publicly available genome-wide association studies (GWASs) in the UK Biobank, and the outcomes of 14 CVDs were obtained from the FinnGen consortium. A total of 49 single -nucleotide polymorphisms (SNPs) were used as the instrumental variables. The effect estimates were calculated by using the inversevariance weighted method. RESULTS The MR analyses showed that genetically predicted daytime napping was associated with an increased risk five CVDs, including heart failure (odds ratio (OR): 1.71, 95% CI: 1.19-2.44, p = 0.003), hypertension (OR: 1.51, 95% 1.05-2.16, p = 0.026), atrial fibrillation (OR: 1.71, 95% CI: 1.02-2.88, p = 0.042), cardiac arrythmias (OR: 1.47, 95% 1.47, 95% CI: 1.01-2.13, p = 0.042) and coronary atherosclerosis (OR: 1.77, 95% CI: 1.17-2.68, p = 0.006). No significant influence was observed for other CVDs. CONCLUSION This two -sample MR analysis suggested that daytime napping was causally associated with an increased risk of heart failure, hypertension, atrial fibrillation, cardiac arrythmias and coronary atherosclerosis. (Hellenic Journal of Cardiology 2024;75:26-31) (c) 2023 Hellenic Society of Cardiology. Publishing services by Elsevier B.V. This is an open access article under the CC BY -NC -ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).