Association of hemoglobin-to-red blood cell distribution width ratio (HRR) and sleep duration with stroke: A cross-sectional study from NHANES 2008–2018

Stroke remains one of the leading causes of death and disability worldwide, with complex associated factors including both hematological markers and lifestyle variables. While red blood cell distribution width (RDW) and the hemoglobin-to-red blood cell distribution width ratio (HRR) have been linked to stroke prevalence, and sleep duration is known to be associated with cerebrovascular health, their combined associations with stroke prevalence have not been well studied. Therefore, this study aims to investigate the comprehensive associations of HRR and sleep duration with stroke prevalence. Data from 22,956 participants were analyzed, with HRR calculated as the ratio of hemoglobin to RDW concentration, and sleep duration categorized into groups based on self-reported hours of sleep per night. Stroke was defined as a self-reported history of stroke. Multivariable logistic regression models were employed to assess the associations of HRR and sleep duration with stroke, adjusting for demographic and health-related covariates. Restricted cubic splines (RCS) were used to examine nonlinear relationships. Subgroup analyses and interaction effects were also explored. Higher HRR values were observed to be associated with stroke prevalence in this cross-sectional analysis, particularly when HRR exceeded 3.04. For sleep duration, both short (<6.40 hours) and long (>7.01 hours) sleep durations were associated with higher stroke prevalence, while moderate sleep duration (6.40–7.01 hours) appeared to show a protective association. Subgroup analyses indicated stronger associations in females, individuals younger than 50 years, African Americans, and those with hypertension or hyperlipidemia. Interaction analysis revealed that the association between HRR and stroke prevalence was modified by age, poverty index ratio, and hypertension. This cross-sectional study demonstrates that both HRR and sleep duration are independently and interactively associated with stroke prevalence, with nonlinear thresholds identified for both variables. These results highlight HRR as a hematological indicator associated with stroke prevalence and underscore the association of balanced sleep duration with lower stroke prevalence. The identification of subgroups with stronger associations and the underlying molecular mechanisms warrant further investigation to refine stroke prevention strategies.