Temporal Trends in Stroke Prevalence and Associated Risk Factors in the United States: Insights From National Health and Nutrition Examination Survey (NHANES) 1999-2020

INTRODUCTION: Stroke is a leading cause of mortality and disability in the United States (US). Although hypertension, diabetes, and obesity are considered traditional risk factors for stroke, the extent to which these factors have changed their relationship and the prevalence of stroke has not been well-characterized since 1999. Therefore, the objective of this study is to investigate the temporal trends in stroke prevalence among US adults and to determine how stroke risk factors have changed over the past 20 years. METHODS: To achieve this objective, we conducted a secondary analysis of NHANES 1999-2020 data using a cross-sectional approach. Further, the prevalence of stroke was self-reported physician diagnosis, and major risk factors (hypertension, diabetes, obesity, smoking, and hyperlipidemia) were measured on standardized NHANES definitions. Temporal trends and associations within cycles were assessed using the survey-weighted logistic regression and age-adjusted prevalence estimates. RESULTS: The findings indicate that the age-adjusted prevalence of stroke among US adults aged ≥20 years increased significantly across all NHANES cycles (1999-2020) during the study period. The highest burden was observed in older adults, men, and non-Hispanic Black persons. Hypertension and diabetes were the strongest risk factors, while the contribution of obesity increased, and that of smoking decreased. CONCLUSION: The study concluded that stroke prevalence in the US has increased in the last 20 years due to the continuous presence of vascular risk factors and the alteration of lifestyle patterns. Such findings highlight the importance of preventive and risk-mitigation interventions, especially for high-risk populations.