Association between high-density lipoprotein-related inflammation index and prevalence of sleep disorders with depression as a mediator.

Background: Sleep disorders have a significant impact on physical health, mental health, and daily functioning, exacerbated by the accelerating pace of life and rising work-related stress in contemporary society. The incidence of sleep disorders continues to rise annually, becoming a significant global public health issue. The white blood cell-to-HDL-cholesterol ratio (WHR), lymphocyte-to-HDL-cholesterol ratio (LHR), monocyte-to-HDL-cholesterol ratio (MHR), neutrophil-to-HDL-cholesterol ratio (NHR), and platelet-to-HDL-cholesterol ratio (PHR) are emerging, convenient, and cost-effective biomarkers that reflect systemic inflammation and immunometabolic status. Given the growing evidence linking chronic inflammation and dysregulated immune responses to prevalence of sleep disorders, exploring the association between these hematologic-lipid ratios and prevalence of sleep disorders may provide novel insights into underlying pathophysiological mechanisms.

Methods: The study included a diverse and extensive sample of 43,273 participants, selected from the National Health and Nutrition Examination Survey (NHANES) conducted between 2005 and March 2020. The association between HDL- associated inflammatory biomarkers and prevalence of sleep disorders was explored using a multivariate logistic regression model with weighted analysis. In addition, the mediating role of depression levels (PHQ-9) between HDL-associated inflammatory markers and prevalence of sleep disorders was examined.

Results: This study suggests that higher levels of MHR and PHR were associated with an increased risk of sleep disorders, with a more pronounced association observed for MHR among male smokers and individuals with comorbidities, and for PHR among males and those with comorbidities. Mediation analysis demonstrates that depression level (PHQ-9) plays a significant mediating role between prevalence of sleep disorders and MHR or PHR.

Conclusion: Elevated MHR and PHR levels were significantly associated with an increased risk of sleep disorders. The association of MHR was particularly pronounced among male smokers and individuals with comorbidities, while PHR showed stronger associations in males and those with comorbidities. Depression levels partially mediated these associations. MHR and PHR may serve as clinically useful biomarkers for identifying high-risk individuals, supporting the need for early screening and intervention. Future longitudinal studies are warranted to confirm causality and assess whether targeting these indices can improve sleep outcomes.