Effects of low-sodium diet vs. high-sodium diet on blood pressure, renin, aldosterone, catecholamines, cholesterol, and triglyceride (cochrane review)

Background The question of whether reduced sodium intake is effective as a health prophylaxis initiative is unsolved. The purpose was to estimate the effects of low-sodium vs. high-sodium intake on blood pressure (BP), renin, aldosterone, catecholamines, and lipids.MethodsStudies randomizing persons to low-sodium and high-sodium diets evaluating at least one of the above outcome parameters were included. Data were analyzed with Review Manager 5.1. Results A total of 167 studies were included. The effect of sodium reduction in: (i) Normotensives: Caucasians: systolic BP (SBP) 1.27mmHg (95% confidence interval (CI): 1.88, 0.66; P = 0.0001), diastolic BP (DBP) 0.05mmHg (95% CI: 0.51, 0.42; P = 0.85). Blacks: SBP 4.02mmHg (95% CI: 7.37, 0.68; P = 0.002), DBP 2.01 mm Hg (95% CI: 4.37, 0.35; P = 0.09). Asians: SBP 1.27mmHg (95% CI: 3.07, 0.54; P = 0.17), DBP 1.68mmHg (95% CI: 3.29, 0.06; P = 0.04). (ii) Hypertensives: Caucasians: SBP 5.48mmHg (95% CI: 6.53, 4.43; P < 0.00001), DBP 2.75mmHg (95% CI: 3.34, 2.17; P < 0.00001). Blacks: SBP 6.44mmHg (95% CI: 8.85, 4.03; P = 0.00001), DBP 2.40mmHg (95% CI: 4.68, 0.12; P = 0.04). Asians: SBP 10.21mmHg (95% CI: 16.98, 3.44; P = 0.003), DBP 2.60mmHg (95% CI: 4.03, 1.16; P = 0.0004). Sodium reduction resulted in significant increases in renin (P < 0.00001), aldosterone (P < 0.00001), noradrenaline (P < 0.00001), adrenaline (P < 0.0002), cholesterol (P < 0.001), and triglyceride (P < 0.0008). Conclusion sSodium reduction resulted in a significant decrease in BP of 1% (normotensives), 3.5% (hypertensives), and a significant increase in plasma renin, plasma aldosterone, plasma adrenaline, and plasma noradrenaline, a 2.5% increase in cholesterol, and a 7% increase in triglyceride. This article is based on a Cochrane Review published in the Cochrane Database of Systematic Reviews (CDSR) 2011, Issue 11, DOI: 10.1002/14651858.CD004022.pub3 (see www.thecochranelibrary.com for information). Cochrane Reviews are regularly updated as new evidence emerges and in response to feedback, and the CDSR should be consulted for the most recent version of the review.