Baseline Plasma Zinc and Risk of First Stroke in Hypertensive Patients

Abstract

Background and Purpose— We aimed to examine the relation of baseline plasma zinc with the risk of first stroke and investigate any possible effect modifiers in hypertensive patients. Methods— The study population was drawn from the CSPPT (China Stroke Primary Prevention Trial), using a nested case-control design, including 599 first stroke cases and 599 matched controls. Results— Compared with participants with baseline plasma zinc <106.9 μg/dL (median), a significantly lower risk of first hemorrhagic stroke was found in those with plasma zinc ≥106.9 μg/dL (multivariate-adjusted odds ratio, 0.45; 95% CI, 0.21–0.94). Furthermore, the inverse plasma zinc-first hemorrhagic stroke association was significantly stronger in participants with body mass index ≥25.0 kg/m 2 or plasma copper <100.1 μg/dL at baseline ( P interaction <0.05 for both variables). However, there was no significant association between plasma zinc and first ischemic stroke (<103.3 versus ≥103.3 μg/dL [median]; multivariate-adjusted odds ratio, 1.16; 95% CI, 0.83–1.61). Conclusions— In this sample of hypertensive patients, we found a significant, inverse association between plasma zinc and first hemorrhagic stroke. Clinical Trial Registration— URL: https://www.clinicaltrials.gov . Unique identifier: NCT00794885.