Associations Between Snoring, Body Mass Index and Coronary Artery Diseases: Observational and Mendelian Randomization Study in Asia.

Background and objective: Previous observational studies reported a complex relationship between snoring and coronary artery disease (CAD). We aimed to estimate the causal associations between snoring and CAD among East Asian people, and the effects independent of BMI.

Methods: Based on 497,250 adults from China Kadoorie Biobank (CKB), we performed a conventional prospective analysis between snoring and CAD outcomes, using the multivariable Cox regression. We also leveraged genome-wide association (GWAS) summary statistics of snoring and BMI from CKB (n = 100,626, 47,208 snorers) and CAD outcomes from Biobank of Japan (BBJ, 5891-25,892 cases, 142,336-168,186 controls). Single-variable and multivariable two-sample bi-directional Mendelian randomization (MR) analyses were performed.

Results: During a median follow-up of 12.32 years, 48,997 participants developed CAD. Snoring and habitual snoring were associated with incident CAD and myocardial infarction (MI), habitual snoring was also associated with stable angina pectoris (SAP). The HRs (95% CIs) of habitual snoring were 1.06 (1.04, 1.08), 1.06 (1.04, 1.08) and 1.14 (1.03, 1.25). The associations remained among non-adiposity participants. Genetically predicted habitual snoring was associated with CAD and MI, the corresponding IVW-ORs (95% CIs) were 1.09 (1.005, 1.19) and 1.15 (1.05, 1.25). Further adjusted BMI, habitual snoring retained independent effects on MI and CAD, and showed impact on SAP (1.09 [1.01, 1.17]). No reverse associations were observed between CADs on snoring traits.

Conclusion: Habitual snoring elevated the risks of total CAD, MI and SAP. The causal associations were independent of BMI. These findings indicated that snoring intervention might contribute to the decrease of CAD risk among Asians.