High salt intake and stroke: meta-analysis of the epidemiologic evidence.

Research on the potential impact of high salt intake on health has grown rapidly over the last decades. Recent studies have suggested that high salt intake could also be associated with adverse effects on cardiovascular system. The review evaluated the current level of epidemiologic evidence on the association between the level of habitual salt intake and stroke outcome. We also suggest further research direction. There were 21 independent samples from 12 studies, with 225,693 participants (follow-up, 3-19 years) and 8135 stroke events. High salt intake was associated with risk of stroke event (pooled odd ratio [OR], 1.34; 95% confidence interval [CI], 1.19-1.51), stroke death (1.40; 1.21-1.63) and stroke onset (1.11; 1.00-1.24), ischemic stroke death (2.15; 1.57-2.95), not associated with risk of ischemic stroke onset (1.07, 0.95-1.2), with no significant evidence of publication bias. High salt intake is associated with significantly increased risk of stroke event. Further research should be directed toward clarifying and quantifying these possible effects and generating testable hypotheses on plausible biologic mechanisms.