Association between iron exposures and stroke in adults: Results from National Health and Nutrition Examination Survey during 2007-2016 in United States

The available findings on the association between iron status and risk of stroke remain controversial. We used multivariable logistic regression and restricted cubic spline models to explore the association between iron exposures and risk of stroke in the US National Health and Nutrition Examination Survey (NHANES 2007-2016, n = 24,627). A total of 941 (3.82%) stroke cases were identified in this study. In women, the ORs with 95% CIs of prevalence of stroke were 0.92 (0.65-1.28), 0.66 (0.44-0.98) and 0.72 (0.49-1.08) across quartiles 2-4 compared with quartile 1 of iron intake, respectively. An inverse and L-shaped association between iron intake and risk of stroke in women was observed, and the curve plateaued at 20 mg/day. However, neither serum iron concentrations nor iron intake were significantly associated with riskof stroke in men. Our study found that iron intake was inversely associated with risk of stroke in a sex-dependent fashion.