Supplementary Material for: Associations Between Cumulative Social Determinants of Health and Stroke Prevalence in U.S. Adults: NHANES 2005–2018

Abstract Background: Social determinants of health (SDoH) are increasingly recognized as key contributors to stroke prevalence, yet few studies have examined their cumulative impact. This study aimed to evaluate the associations between multiple SDoH and stroke prevalence, and identify the primary drivers of cumulative social disadvantage. Methods: We analyzed data from 26703 participants in the 2005–2018 NHANES cycles. Stroke history was self–reported. Eight SDoH indicators—including income, education, employment, food security, housing stability, marital status, healthcare access, and insurance coverage—were assessed. Associations with stroke were examined using survey-weighted logistic regression. A weighted quantile sum (WQS) index was constructed from six of these indicators (excluding marital status and healthcare access) to evaluate the cumulative effect of SDoH and to determine the relative contribution of each factor. Results: Of the study population, 992 (2.6%) reported a history of stroke. Low income, unemployment, food insecurity, and rental housing were significantly associated with stroke prevalence. WQS analysis demonstrated a strong cumulative association between adverse SDoH and stroke (OR = 4.20, 95% CI: 3.24–5.44, P < 0.001), with food insecurity (weight = 0.33), family poverty income ratio (0.33), and housing status (0.20) contributing the most. Subgroup and sensitivity analyses confirmed the robustness of these associations across age, sex, and racial/ethnic groups. Conclusion: Cumulative social disadvantage, particularly food insecurity, low family poverty income ratio, and disadvantaged housing status, is strongly associated with stroke prevalence. Interventions addressing these key social determinants may help reduce stroke burden and underscore the importance of considering multiple SDoH in preventive strategies.