No clear benefit of salt reduction on mortality and cardiovascular morbidity

Clinical question: 
How effective is dietary salt reduction on mortality and cardiovascular morbidity?
Bottom line: 
Intensive support and encouragement to reduce salt intake did lead to a reduction in the amount of salt eaten and a small reduction in blood pressure after more than 6 months. Despite collating more events than previous systematic reviews of randomised controlled trials (665 deaths in 6250 participants), it was not possible to demonstrate a robustly estimated effect of reduced dietary salt on mortality or cardiovascular morbidity in normotensive or hypertensive populations. Salt restriction increased the risk of all-cause death in those with congestive heart failure.
Caveat: 
The methods of achieving salt reduction in the trials included in the review, as in other systematic reviews, were relatively modest in their impact on sodium excretion and on blood pressure levels. Such generally requires considerable efforts to implement and would not be expected to have a major impact on the burden of CVD. There was no information on participants’ health-related quality of life.
Context: 
Cardiovascular disease is a major cause of premature death and disability. Data from observational studies have indicated a high dietary intake of salt is an important risk factor for cardiovascular disease.1
Review CD#: 
CD009217
PEARLS No: 
327
Date: 
September, 2011
Authored by: 
Brian R McAvoy