Effect of lower sodium intake on health: systematic review and meta-analyses
ABSTRACT To assess the effect of decreased sodium intake on blood pressure, related cardiovascular diseases, and potential adverse effects such as changes in blood lipids, catecholamine levels, and renal function.
Systematic review and meta-analysis.
Cochrane Central Register of Controlled Trials, Medline, Embase, WHO International Clinical Trials Registry Platform, the Latin American and Caribbean health science literature database, and the reference lists of previous reviews.
Randomised controlled trials and prospective cohort studies in non-acutely ill adults and children assessing the relations between sodium intake and blood pressure, renal function, blood lipids, and catecholamine levels, and in non-acutely ill adults all cause mortality, cardiovascular disease, stroke, and coronary heart disease. STUDY APPRAISAL AND SYNTHESIS: Potential studies were screened independently and in duplicate and study characteristics and outcomes extracted. When possible we conducted a meta-analysis to estimate the effect of lower sodium intake using the inverse variance method and a random effects model. We present results as mean differences or risk ratios, with 95% confidence intervals.
We included 14 cohort studies and five randomised controlled trials reporting all cause mortality, cardiovascular disease, stroke, or coronary heart disease; and 37 randomised controlled trials measuring blood pressure, renal function, blood lipids, and catecholamine levels in adults. Nine controlled trials and one cohort study in children reporting on blood pressure were also included. In adults a reduction in sodium intake significantly reduced resting systolic blood pressure by 3.39 mm Hg (95% confidence interval 2.46 to 4.31) and resting diastolic blood pressure by 1.54 mm Hg (0.98 to 2.11). When sodium intake was <2 g/day versus ≥2 g/day, systolic blood pressure was reduced by 3.47 mm Hg (0.76 to 6.18) and diastolic blood pressure by 1.81 mm Hg (0.54 to 3.08). Decreased sodium intake had no significant adverse effect on blood lipids, catecholamine levels, or renal function in adults (P>0.05). There were insufficient randomised controlled trials to assess the effects of reduced sodium intake on mortality and morbidity. The associations in cohort studies between sodium intake and all cause mortality, incident fatal and non-fatal cardiovascular disease, and coronary heart disease were non-significant (P>0.05). Increased sodium intake was associated with an increased risk of stroke (risk ratio 1.24, 95% confidence interval 1.08 to 1.43), stroke mortality (1.63, 1.27 to 2.10), and coronary heart disease mortality (1.32, 1.13 to 1.53). In children, a reduction in sodium intake significantly reduced systolic blood pressure by 0.84 mm Hg (0.25 to 1.43) and diastolic blood pressure by 0.87 mm Hg (0.14 to 1.60).
High quality evidence in non-acutely ill adults shows that reduced sodium intake reduces blood pressure and has no adverse effect on blood lipids, catecholamine levels, or renal function, and moderate quality evidence in children shows that a reduction in sodium intake reduces blood pressure. Lower sodium intake is also associated with a reduced risk of stroke and fatal coronary heart disease in adults. The totality of evidence suggests that most people will likely benefit from reducing sodium intake.
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ABSTRACT: Background: Dietary sodium and potassium are involved in the pathogenesis of cardiovascular disease. Data exploring the cardiovascular outcomes associated with these electrolytes within Australian children is sparse. Furthermore, an objective measure of sodium and potassium intake within this group is lacking. Objective: The primary aim of the Salt and Other Nutrient Intakes in Children (“SONIC”) study was to measure sodium and potassium intakes in a sample of primary schoolchildren located in Victoria, Australia, using 24-hour urine collections. Secondary aims were to identify the dietary sources of sodium and potassium, examine the association between these electrolytes and cardiovascular risk factors, and assess children’s taste preferences and saltiness perception of manufactured foods. Methods: A cross-sectional study was conducted in a convenience sample of schoolchildren attending primary schools in Victoria, Australia. Participants completed one 24-hour urine collection, which was analyzed for sodium, potassium, and creatinine. Completeness of collections was assessed using collection time, total volume, and urinary creatinine. One 24-hour dietary recall was completed to assess dietary intake. Other data collected included blood pressure, body weight, height, waist and hip circumference. Children were also presented with high and low sodium variants of food products and asked to discriminate salt level and choose their preferred variant. Parents provided demographic information and information on use of discretionary salt. Descriptive statistics will be used to describe sodium and potassium intakes. Linear and logistic regression models with clustered robust standard errors will be used to assess the association between electrolyte intake and health outcomes (blood pressure and body mass index/BMI z-score and waist circumference) and to assess differences in taste preference and discrimination between high and low sodium foods, and correlations between preference, sodium intake, and covariates. Results: A total of 780 children across 43 schools participated. The results from this study are expected at the end of 2015. Conclusions: This study will provide the first objective measure of sodium and potassium intake in Australian schoolchildren and improve our understanding of the relationship of these electrolytes to cardiovascular risk factors. Furthermore, this study will provide insight into child taste preferences and explore related factors. Given the cardiovascular implications of consuming too much sodium and too little potassium, monitoring of these nutrients during childhood is an important public health initiative.01/2015; 4(1). DOI:10.2196/resprot.3994
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ABSTRACT: High blood pressure is the cause of almost 13 % of all deaths in the world. DASH (Dietary Approaches to Stop Hypertension) is "gold standard" in diet recommended by American Society of Hypertension, American Heart Association and Dietary Guidelines for Americans 2010 for reduction many CV risk factors including hypertension. Non-pharmacological treatment of hypertension through DASH dietary program with reduction of salt intake can significantly reduce high values of blood pressure and decrease general cardiovascular risks. The aim of this research is to determine the prevalence of hypertension among miners in Banovici coal mine and amount of salt taken in meals during work time. We inspected the medical documentation and registers for all employees in coal mine Banovici in order to provide calculation of hypertension prevalence. Based on reports and company standards on grocery usage and average amount of salt used in preparation of one meal in coal mine kitchen, we have calculated the average consumption of salt of one employee per meal. There are 2700 of employees in coal mine Banovici with average life age of 46 years. From them 694 (25.7%) miners have arterial hypertension. Also 707023 kg of salt is being spent for preparation of meals in coal mine kitchen on yearly basis. Employees take between 4-9 grams of salt per one meal excluding the salt contained in bread. the amount of salt intake per one meal in the coal mine kitchen is larger from daily doses recommended by ACC/AHA.Materia Socio Medica 12/2014; 26(6):385-8. DOI:10.5455/msm.2014.26.385-388
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ABSTRACT: Cardiovascular disease is a major cause of morbidity and mortality worldwide, hypertension being one of their most prevalent risk factors. Information on health related quality of life (QOL) of hypertensive individuals in Lebanon is lacking. Our objectives were to evaluate QOL of hypertensive patients compared with non-hypertensive subjects and to suggest possible predictors of QOL in Lebanon. We conducted a case control study among individuals visiting outpatient clinics. Quality of life was assessed using the eight item (SF-8) questionnaire administered face to face to the study population, applied to hypertensive (N=224) and non-hypertensive control (N=448) groups. Hypertensive patients presented lower QOL scores in all domains, particularly in case of high administration frequency and occurrence of drug related side effects. Among hypertensive patients, QOL was significantly decreased with the presence of comorbidities (β=-13.865, p=0.054), daily frequency of antihypertensive medications (β=-8.196, p<0.001), presence of drug side-effects (β=-19.262, p=0.031), older age (β=-0.548, p<0.001), female gender (β=-21.363, p=0.05), lower education (β=-22.949, p=0.006), and cigarettes smoked daily (β=-0.726, p<0.001); regular sport activity (β=23.15, p<0.001) significantly increased quality of life. These findings indicate the necessity for health professionals to take these factors into account when treating hypertensive patients, and to tackle special subgroups with attention to their deteriorated QOL. Copyright © 2015. Published by Elsevier Ltd.02/2015; DOI:10.1016/j.jegh.2015.02.003