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Salt intake, stroke, and cardiovascular disease : meta-analysis of prospective studies

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Strazzullo, Pasquale, Elia, Lanfranco d', Kandala, Ngianga-Bakwin and Cappuccio, Francesco P.. (2009) Salt intake, stroke, and cardiovascular disease : meta-analysis of prospective studies. BMJ, Vol.339 . b4567. ISSN 0959-535X

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Official URL: http://dx.doi.org/10.1136/bmj.b4567

Abstract

Objective: To assess the relation between the level of habitual salt intake and stroke or total cardiovascular disease outcome. Design: Systematic review and meta-analysis of prospective studies published 1966-2008. Data sources: Medline (1966-2008), Embase (from 1988), AMED (from 1985), CINAHL (from 1982), Psychinfo (from 1985), and the Cochrane Library. Review methods: For each study, relative risks and 95% confidence intervals were extracted and pooled with a random effect model, weighting for the inverse of the variance. Heterogeneity, publication bias, subgroup, and meta-regression analyses were performed. Criteria for inclusion were prospective adult population study, assessment of salt intake as baseline exposure, assessment of either stroke or total cardiovascular disease as outcome, follow-up of at least three years, indication of number of participants exposed and number of events across different salt intake categories. Results: There were 19 independent cohort samples from 13 studies, with 177 025 participants (follow-up 3.5-19 years) and over 11 000 vascular events. Higher salt intake was associated with greater risk of stroke (pooled relative risk 1.23, 95% confidence interval 1.06 to 1.43; P=0.007) and cardiovascular disease (1.14, 0.99 to 1.32; P=0.07), with no significant evidence of publication bias. For cardiovascular disease, sensitivity analysis showed that the exclusion of a single study led to a pooled estimate of 1.17 (1.02 to 1.34; P=0.02). The associations observed were greater the larger the difference in sodium intake and the longer the follow-up. Conclusions: High salt intake is associated with significantly increased risk of stroke and total cardiovascular disease. Because of imprecision in measurement of salt intake, these effect sizes are likely to be underestimated. These results support the role of a substantial population reduction in salt intake for the prevention of cardiovascular disease.

Item Type:	Journal Article
Subjects:	R Medicine > RC Internal medicine
Divisions:	Faculty of Medicine > Warwick Medical School > Warwick Evidence Faculty of Medicine > Warwick Medical School > Health Sciences Faculty of Medicine > Warwick Medical School > Metabolic and Vascular Health Faculty of Medicine > Warwick Medical School
Library of Congress Subject Headings (LCSH):	Salt -- Physiological effect -- Research, Cardiovascular system -- Diseases, Cerebrovascular disease -- Nutritional aspects
Journal or Publication Title:	BMJ
Publisher:	BMJ Group
ISSN:	0959-535X
Date:	24 November 2009
Volume:	Vol.339
Number of Pages:	9
Page Range:	b4567
Identification Number:	10.1136/bmj.b4567
Status:	Peer Reviewed
Publication Status:	Published
Access rights to Published version:	Open Access
Funder:	Seventh Framework Programme (European Commission) (FP7)
Grant number:	FP7-HEALTH- 2007-201550 (FP7)
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URI:	http://wrap.warwick.ac.uk/id/eprint/2440