J Korean Soc Hypertens.  2012 Jun;18(2):53-62. 10.5646/jksh.2012.18.2.53.

Salt, Hypertension, and Cardiovascular Diseases

• Kawano Y

• KMID: 1436341
• DOI: http://doi.org/10.5646/jksh.2012.18.2.53

Abstract

The relationship between salt and hypertension is well established, and salt restriction is widely recommended in the management of hypertension. However, people living in northeast Asia have consumed large amount of salt, and the prevalence of hypertension and the incidence of stroke have been high in that area. Mechanisms of salt-induced hypertension may be complex, but volume expansion in the presence of impaired natriuretic capacity of the kidney and action on the central nervous system and neurohormoral pathways seem to be important. Salt is also involved in changes in blood pressure (BP) caused by other factors, such as weight gain, stress, exercise, potassium, catecholamines, angiotensin, and aldosterone. The interaction between sodium and aldosterone appears to play a critical role in the development of organ damage. The depressor effect of salt restriction in hypertensive patients is well demonstrated although the response of BP varies widely among individuals. Salt restriction decreases BP throughout 24 hours, and its effect may be greater during night compared to daytime in salt-sensitive nondippers. Although excess salt consumption can cause cardiovascular diseases through its effect on BP, recent studied have shown that the association of salt consumption and cardiovascular diseases, such as stroke and heart failure, is independent of BP. Salt reduction is important in the prevention of cardiovascular diseases, however, the effect and safety of aggressive salt restriction remain to be clarified. It is difficult to accomplish and maintain the salt reduction. Both population strategy and individualized approach are important to reduce salt consumption.

Keyword

Salt; Sodium; Blood pressure; Hypertension; Cardiovascular diseases

MeSH Terms

Aldosterone
Angiotensins
Asia
Blood Pressure
Cardiovascular Diseases
Catecholamines
Central Nervous System
Heart Failure
Humans
Hypertension
Incidence
Kidney
Potassium
Prevalence
Sodium
Stroke
Weight Gain
Aldosterone
Angiotensins
Catecholamines
Potassium
Sodium

Figure

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  Fig. 1 Relationship between salt intake and systolic blood pressure (BP) (Modified from Intersalt Cooperative Research Group. BMJ. 1988;297:319-28).6)

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  Fig. 2 Recent trend of salt consumption in Japan (Modified from Anderson, et al. J Am Diet Assoc. 2010;110:736-45, with permission from).18)

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  Fig. 3 Distribution of estimated salt intake in treated hypertensive patients at the Hypertension Clinic of National Cerebral and Cardiovascular Center in 2007.

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  Fig. 4 Effects of moderate salt reduction on blood pressureBP according to a meta-analysis of randomized clinical trials (From He and MacGregor. J Hum Hypertens. 2002;16:761-70, with permission from).8)

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  Fig. 5 Salt intake and stroke mortality in Japanese men and women (From Nagata, et al. Stroke. 2004;35:1543-7, with permission from).56)

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