Lifestyle risk factors and stroke: findings from the national health and nutrition examination survey (1999–2020) and a Mendelian randomization analysis

This study aimed to assess the relationship between lifestyle risk factors and stroke, as well as to quantify causality, using data from the National Health and Nutrition Examination Survey (NHANES) and Mendelian randomization (MR).
We analyzed data from 28,226 individuals who participated in NHANES between 1999 and 2020. To evaluate the association between lifestyle risk factors and stroke, we used weighted multivariate logistic regression. Genome-wide association study (GWAS) summary data were utilized to conduct bidirectional two-sample MR and multivariate MR analyses.
The NHANES observational study found that waist circumference, smoking, and creatinine were consistently and positively associated with stroke in multivariable-adjusted models, with odds ratios (OR) of 1.010 (95% confidence interval [CI], 1.001–1.019, p = 0.046), 1.653 (95% CI, 1.310–2.084, p < 0.001), and 1.400 (95% CI, 1.183–1.657, p < 0.001), respectively. Conversely, engaging in vigorous physical activities was a protective factor against stroke, with an OR of 0.572 (95% CI, 0.342–0.961, p = 0.037). Bidirectional two-sample and multivariate MR analyses revealed a causal link between smoking, waist circumference, and stroke (OR = 1.237, 95% CI, 1.130–1.354; OR = 1.239, 95% CI, 1.149–1.335, respectively).
Vigorous activities, especially fitness and recreational activities, serve as a protective factor against stroke. Smoking and increased waist circumference represent consistent lifestyle-related risk factors for stroke.