The mediating role of remnant cholesterol in the association between obstructive sleep apnea and diabetes: insights from two independent datasets.

PURPOSE: Obstructive sleep apnea (OSA) is a well-established risk factor for diabetes mellitus (DM), with lipid metabolism disorders implicated in its pathogenesis. The aim of this study is to explore the role of remnant cholesterol (RC), a novel lipid parameter with potentially greater predictive value for DM compared to traditional lipids, in the OSA-DM relationship.

METHODS

This study included participants collected between 2000 and 2023 from the Sun Yat-sen Memorial Hospital (SYSMH) and from the National Health and Nutrition Examination Survey (NHANES) datasets for 2005-2008 and 2015-2018. Mediation analyses were conducted to investigate the role of RC in the OSA-DM relationship and to quantify its effect. Restricted cubic spline (RCS) regression was applied to analyze the association between RC and DM among participants with OSA.

RESULTS

A total of 3,260 participants from the SYSMH dataset and 9,825 from NHANES were analyzed. A positive association was observed between OSA and RC, RC and DM, and OSA and DM. Mediation analysis revealed that RC mediated the OSA-DM relationship with a significant mediation effect of 10.13% (SYSMH) and 10.02% (NHANES) (both P < 0.001). Furthermore, RCS regression analysis demonstrated a positive relationship between RC and DM in patients with OSA across both datasets.

CONCLUSIONS

RC mediates the OSA-DM relationship and is positively associated with DM in patients with OSA. These findings provide novel insights into the pathophysiological mechanisms linking OSA to DM and highlight RC as a potentially valuable biomarker for assessing DM risk in patients with OSA.