Skip to main content

Currently Skimming:

4 Sodium Intake and Health Outcomes
Pages 57-118

The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.


From page 57...
... . Excess dietary sodium has been identified as a potential etiologic risk factor for CVD, based on evidence for a dose-dependent increase in blood pressure in response to increasing sodium intake, as well as evidence from studies published before 2003 of sodium intake and risk of stroke or coronary heart disease (IOM, 2005)
From page 58...
... Each study is described by its population, size, and characteristics; study design, purpose, and length; sodium intake measure and method; range of intake, reference intake, and adjustments; outcome measure, confounders, and adjustments; and direction and significance of effect. For each major outcome of CVD, CHF, and CKD, the committee provides a summary table evaluating each study using as criteria the generalizability of the study population to U.S.
From page 59...
... Study design, purpose, and length This secondary analysis of NHANES data was carried out to assess the potential impact of dietary sodium intake on risk of CVD and all-cause mortality over a mean of 13.7 years of follow-up. Sodium intake measure and method Dietary sodium intake was assessed from a 24-hour dietary recall administered in the NHANES survey.
From page 60...
... Study design, purpose, and length This secondary analysis of NHANES data was carried out to assess the potential impact of dietary sodium on risk of CVD and all-cause mortality over a mean period of 8.7 years. Sodium intake measure and method Energy-adjusted dietary sodium intake was estimated from one 24-hour dietary recall.
From page 61...
... . Study design, purpose, and length This multiethnic population-based prospective cohort study examined associations between sodium consumption and risk of stroke and combined vascular events (stroke, myocardial infarction [MI]
From page 62...
... Analytic models were adjusted for demographics, behavioral risk factors, and vascular risk factors (diabetes, hypercholesterolemia, hypertension, and continuous blood pressure measurements)
From page 63...
... Multivariate analysis adjusted for age, supplementation group, number of cigarettes smoked daily, BMI, systolic and diastolic blood pressure, serum total cholesterol and highdensity cholesterol, as well as history of diabetes and coronary heart disease, leisure-time physical activity, and intake of alcohol and total energy. Direction and significance of effect The analyses found no significant association between dietary sodium intake and risk of any stroke subtype (p for trend for multivariate relative risk [RR]
From page 64...
... (2011) obtained data from two population-based prospective cohort studies (the Flemish Study on Environment, Genes, and Health Outcomes and the European Project on Genes in Hypertension)
From page 65...
... Study design, purpose, and length This study prospectively examined associations between sodium and changes in blood pressure and risk of CVD mortality and all-cause mortality over a median of 7.9 years. Sodium intake measure and method Timed 24-hour urine samples were collected 1 week following blood pressure measurements and analyzed for sodium and potassium.
From page 66...
... until December 31, 2004. Sodium intake measure and method Dietary sodium intake data were determined from a 138-item FFQ that included cooking salt, soy sauce, table salt, and other salty condiments.
From page 67...
... 40-79 years of age. Study design, purpose, and length This large prospective study examined associations between dietary sodium intake and mortality from stroke; stroke related to subarachnoid hemorrhage, intraparenchymal hemorrhage, or ischemic stroke; coronary heart disease; and total CVD over a mean follow-up period of 12.7 years.
From page 68...
... TABLE 4-1 Weaknesses and Strengths of Population Studies and Methods of Studies on Cardiovascular Health Outcomes: CVD Outcomes in General Populations Sample Size and Method to Assess Study Population Study Design Sodium Intake Cohen et al., 2006 Strengths Strengths Weaknesses Good Prospective cohort 24-h recall, only one generalizability day recorded to the general population (U.S.)
From page 69...
... (2008) , the investigators elected not to adjust for measured blood pressure or antihypertensive treatment, arguing that these factors may be in the causal pathway linking dietary sodium to health outcomes.
From page 70...
... 70 SODIUM INTAKE IN POPULATIONS TABLE 4-1 Continued Sample Size and Method to Assess Study Population Study Design Sodium Intake Cohen et al., 2008 Strengths Strengths Weaknesses Good Prospective cohort 24-h recall, only 1 day generalizability recorded to the general population (U.S.) Na intake adjusted for added salt instead of including in exposure Gardener et al., Strengths Strengths Strengths 2012 Good Population-based Na consumption generalizability prospective cohort assessed over previous to the general year; population (U.S.)
From page 71...
... Weaknesses Weaknesses Adjusted for blood pressure and hypertension, Caloric intake could be which could be in the underreported in individuals causal pathway with low Na intake, leading to a systematic error Strengths Strengths Strengths ≤1,500-10,000 mg/d Analysis conducted with Eliminated patients with and without adjustment extreme Na and caloric intake for vascular risk factors and those with stroke and MI continued
From page 72...
... Added salt considered Stolarz-Skrzypek et Strengths Strengths Strengths al., 2011 Good generaliza- Population-base UNa collection bility to the general prospective cohort population (Dutch) Elimination of low 24-h urine volume and extreme 24-h urine creatinine 24-h urine collection Weaknesses Creatinine data suggest undercollection of urine specimens in lowest tertile No assessment of dietary intake and thus, no ability to adjust for caloric intake
From page 73...
... 6,613 and 3,799-5,930 tobacco and alcohol use mg/d for men and women, respectively) Na intake adjusted for education Strengths Strengths Weaknesses 2,461-5,980 mg/d Na intake adjusted for Individuals in lower Na urinary K, BMI, DM, tertiles were older and less education, and tobacco educated and alcohol use Weaknesses Adjusted for blood pressure and hypertension, which may be in the causal pathway continued
From page 74...
... Using 7.4% of the participants with second day 24-h recalls to estimate usual sodium intake accounting for within-person variation in intake NOTES: Sodium intake presented as mmol in a study was converted to mg using 23 mg/mmol. BMI, body mass index; BP, blood pressure; CHD, coronary heart disease; CVD, cardiovascular disease; d, day; DM, diabetes mellitus; FFQ, food frequency questionnaire; h, hour; K, potassium; mg, milligram; MI, myocardial infarction; Na, sodium, UNa, urinary sodium.
From page 75...
... SODIUM INTAKE AND HEALTH OUTCOMES 75 Sodium Intake Levels or Adjustment for Intake Ranges Confounders Other Strengths Strengths Strengths 3,084-6,844 mg/d Na intake adjusted for Eliminated patients with caloric intake, BMI, and self-reported CVD and cancer tobacco and alcohol use (reverse causation) and those with extreme caloric intake Strengths Strengths Strengths 2,323-6,256 mg/d Adjustment for K intake Eliminated patients with self reported CVD and cancer Na intake adjusted for DM, caloric intake, BMI, tobacco and alcohol use, and education Strengths Strengths 2,176-5,135 mg/d for the Conducted analysis with and without adjustment for BP 12.5 and 87.5 percentiles Na intake adjusted for family history of CVD, education, Intake range=839-8,555 caloric intake, and tobacco and alcohol use mg/d Na intake adjusted for education Na intake adjusted for DM
From page 76...
... Study design, purpose, and length This case-cohort design examined the relationships between sodium and potassium intake and incidence of MI TABLE 4-2 Weaknesses and Strengths of Population Study and Methods of Studies on Cardiovascular Health Outcomes: CVD Outcomes in Populations 51 Years of Age and Older* Sample Size and Method to Assess Study Population Study Design Sodium Intake Geleijnse et al., Strengths Strengths Weaknesses 2007 Good generaliza- Population-based Single overnight urine bility to the general prospective case- collection (question of population (Dutch)
From page 77...
... Outcome measure, confounders, and adjustments Outcome measures were CVD mortality and all-cause mortality. Mean baseline blood pressure for the cohort was 140 (standard deviation [SD]
From page 78...
... Study design, purpose, and length The purpose of this retrospective cohort study was to determine whether dietary sodium intake was correlated with CVD mortality and all-cause mortality over a period of 31.4 (±13.7) months.
From page 79...
... Study design, purpose, and length This prospective cohort study evaluated whether the effect of randomization to treatment with angiotensin receptor blockers (ARBs) with kidney disease progression and CVD was modified by dietary sodium intake over a period of 30 months.
From page 80...
... . TABLE 4-3 Weaknesses and Strengths of Population Studies and Methods of Studies on Cardiovascular Health Outcomes: CVD Outcomes in CKD Populations Sample Size and Method to Assess Study Population Study Design Sodium Intake Dong et al., Weaknesses Weaknesses Strengths 2010 Poor generalizability Retrospective Repeated 3-d diet to subgroups of cohort records taken over 3 mo interest (men and women receiving peritoneal dialysis, China)
From page 81...
... Study design, purpose, and length This prospective cohort study was carried out to examine the influence of high vs. low sodium intake on inflammatory-oxidative response, cardiac remodeling, ­ and total mortality after MI, for up to 4 years.
From page 82...
... Sodium intake measure and method Dietary sodium intake was estimated from a 62-item validated FFQ. Range of intake, reference, and adjustments Energy-adjusted sodium intake was categorized as either high (≥1,200 mg per day)
From page 83...
... Outcome measure, confounders, and adjustments Outcome measures were cumulative recurrence rates of stroke. Adjustments were made for age and medications.
From page 84...
... Models for analysis were adjusted for age, sex, race/ethnicity, prior history of stroke or MI, creati TABLE 4-4 Weaknesses and Strengths of Population Studies and Methods of Studies on Cardiovascular Health Outcomes: CVD Outcomes in Populations with Preexisting CVD Sample Size and Method to Assess Study Population Study Design Sodium Intake Costa et al., 2012 Weaknesses Strengths Weaknesses Poor Prospective cohort Only 62 items in FFQ generalizability of subgroups of Questionnaire interest (men and validation conducted women with acute among volunteers MI, Brazil) without MI and may be misleading FFQ assessing last 90 d administered within 24 h after MI
From page 85...
... Compared with the reference sodium excretion (4,000-5,990 mg per day) , excretion of 7,000-8,000 (HR=1.15 [CI: 1.00, 1.32]
From page 86...
... BMI, body mass index; BP, blood pressure; CVD, cardiovascular disease; d, day; DM, diabetes mellitus; FFQ, food frequency questionnaire; h, hour; HDL, high-density lipoprotein cholesterol; IS, ischemic stroke; LDL, low-density lipoprotein cholesterol; mg, milligrams; MI, myocardial infarction; Na, sodium; RCT, randomized controlled trial; UK, urinary potassium; UNa, urinary sodium.
From page 87...
... , mg/Na) /d disease; abnormal ankle- and tobacco and alcohol use brachial pressure index; metabolic syndrome Weaknesses Urine specimens collected after acute stroke may be influenced by medications and acute disease and not reflect usual intake Small sample with few outcome events Strengths Strengths Strengths 1,550-9,400 mg/d Adjustments for prior Repeated excluding first year stroke or MI, creatinine, of follow-up Weaknesses BMI, hypertension, DM, atrial fibrillation, Multiple outcomes Estimated mean Na intake smoking, LDL, HDL, of 4,770 mg/d is much treatment allocation (with Detailed data on covariates higher than general U.S.
From page 88...
... . (The original studies were conducted to evaluate the effect of dietary sodium on blood pressure, rather than on health outcomes -- see Chapter 3.)
From page 89...
... . Study design, purpose, and length This prospective cohort study examined relationships between sodium and potassium intake and sodium-topotassium ratio with CVD events among participants from TOHP I and TOHP II over 10-15 years of follow-up.
From page 90...
... The overall median urinary sodium excretion collected over 18 months for all participants was 158 mmol (3,634 mg) /24 hours (interquartile range, 127-194 mmol [2,9214,462 mg]
From page 91...
... Patients with type 1 diabetes or diabetes secondary to medication or pancreatitis were excluded from the study. Study design, purpose, and length This prospective cohort study was carried out to examine associations between dietary sodium intake and all-cause and CVD mortality in patients with type 2 diabetes.
From page 92...
... Sodium intake measure and method Sodium intake was estimated from one 24-hour urinary sodium collected at baseline. Range of intake, reference, and adjustments Urinary sodium excretion was categorized into quartiles.
From page 93...
... Adjustments were made for age, sex, glycemic control, presence and severity of CKD, and total cholesterol and triglycerides. Direction and significance of effect Adjusted multivariate regression analysis found urinary sodium excretion was associated with incident CVD, with
From page 94...
... ACE, angiotensin-converting enzyme; BP, blood pressure; CKD, chronic kidney disease; CVD, cardiovascular disease; d, day; eGFR, estimated glomerular filtration rate; h, hour; mg, milligram; Na, sodium; UNa, urinary sodium. increased risk at both the highest and lowest urine sodium excretion levels.
From page 95...
... SODIUM INTAKE AND HEALTH OUTCOMES 95 Sodium Intake Levels or Adjustment for Intake Ranges Confounders Other Strengths Strengths Weaknesses <3,450-4,784 mg/d Adjustments for duration Individuals in lower Na of diabetes, atrial tertiles were older, with lower fibrillation, presence/ eGFR and less likely to be on severity of CKD ACE inhibitor Na intake adjusted for systolic BP (which had inverse effect on mortality) Potential for reverse causation Strengths Strengths Weaknesses <2,346-4,301 mg/d Adjustment for duration of Risk among those with diabetes, presence/severity extremely low levels of UNa of CKD, presence of likely reflective of poor health established CVD, systolic BP Absolute levels of Na unclear in analysis of CVD Studies in Populations with Congestive Heart Failure The committee also reviewed evidence on the association of sodium intake with CHF.
From page 96...
... All patients were consuming a self-selected diet. Study design, purpose, and length This small prospective cohort study followed participants for 3 years to determine whether a high sodium intake is related to acute decompensated heart failure (ADHF)
From page 97...
... Study design, purpose, and length This small prospective cohort study examined differences in cardiac event-free survival between patients with sodium intake either above or below 3,000 mg per day over a period of 12 months. Sodium intake measure and method Sodium intake was estimated from a single 24-hour urine collection.
From page 98...
... Study design, purpose, and length This RCT was designed to evaluate the effects of dietary sodium restriction at two levels on neurohormonal and cytokine activation and on clinical outcomes over a period of 12 months. Sodium intake measure and method The treatment groups received one of two levels of a prescribed sodium-restricted diet.
From page 99...
... recently hospitalized patients with decompensated CHF NYHA Class II-IV who were 55-83 years of age. Study design, purpose, and length A 2×2×2 factorial double-blinded RCT was used to assess the effect of dietary sodium intake in combination with a diuretic and fluid regimen on risk of mortality.
From page 100...
... The effect of low sodium intake on health outcomes within subgroups by dosage of furosemide and TABLE 4-7 Weaknesses and Strengths of Population Studies and Methods of Studies on Cardiovascular Health Outcomes. Observational Trials: CVD Outcomes in Populations with CHF Sample Size and Method to Assess Study Population Study Design Sodium Intake Arcand et al., 2011 Strengths Strengths Strengths Good generaliza- Prospective cohort Two 3-d food records bility to subgroups validated with 2 urine of interest collections (congestive heart failure, U.S.)
From page 101...
... These included the variability in methodological approaches used to evaluate relationships between sodium intake and risk of health outcomes, study design, limitations in the quantitative measures of both dietary intake and urinary excretion of sodium, confounder adjustment, and the number of relevant studies available. The committee considered studies that determined sodium intake levels through multiple high-quality 24-hour urine collections to be the best design.
From page 102...
... 102 SODIUM INTAKE IN POPULATIONS TABLE 4-8 Weaknesses and Strengths of Population Studies and Methods of Studies on Cardiovascular Health Outcomes. Randomized Control Trials: CVD Outcomes in Populations with CHF Sample Size and Method to Assess Study Population Study Design Sodium Intake Parrinello et al., Weaknesses Strengths Strengths 2009 Limited Randomization 24-hour UNa generalizability due by a preliminary to eligibility criteria computer (unresponsive to algorithm treatment)
From page 103...
... SODIUM INTAKE AND HEALTH OUTCOMES 103 Sodium Intake Levels or Intake Ranges Blinding Other Strengths Strengths Weaknesses 80 vs. 120 mmol/d (1,840 Double blind (no details)
From page 104...
... 104 SODIUM INTAKE IN POPULATIONS TABLE 4-8 Continued Sample Size and Method to Assess Study Population Study Design Sodium Intake Paterna et al., 2008 Weaknesses Strengths Strengths Limited Randomization Multiple written generalizability due was carried standard diets to eligibility criteria out using a containing 80 or 120 (unresponsive to preliminary mmol Na (1,840 or treatment) and computer 2,760 mg)
From page 105...
... SODIUM INTAKE AND HEALTH OUTCOMES 105 Sodium Intake Levels or Intake Ranges Blinding Other Strengths Weaknesses Weaknesses 80 mmol/d vs. 120 mmol/d Unblinded Unclear if analysis was (1,840 mg/d vs.
From page 106...
... The wide range of typical intakes across various population groups, as well as differences in the methods used to measure dietary sodium among different studies, meant that the committee could not derive a numerical definition for high or low intakes in its findings and conclusions. Rather, it could consider sodium intake levels only within the context of an individual study.
From page 107...
... All of the evidence considered was observational, mostly prospective cohort studies that examined associations between sodium intake and risk of adverse health outcomes. The populations studied were disproportionately from outside the United States and many included groups that consumed levels of sodium much higher than 3,400 mg per day, the average amount consumed by U.S.
From page 108...
... found an increased risk of CVD at lower sodium levels, while one study (Yang et al., 2011, also using NHANES III) found a lower risk of all-cause mortality at lower sodium intake levels.
From page 109...
... The committee identified and evaluated three RCTs and two cohort studies that examined associations between sodium intake at low, moderate, and high levels and health outcomes in study participants with CHF at various levels of severity. Although the results from the effects of dietary sodium on outcomes in these participants appear inconsistent, several factors might have contributed to the disparate findings.
From page 110...
... In addition, a cohort study in a population including individuals with 3  The Guidelines for Heart Failure patients of the Heart Failure Association of America de scribes therapies appropriate for the different stages of a patient's health (e.g., decompensated heart failure, reduced ejection fraction, end of life)
From page 111...
... Overall, the studies published since 2003 reviewed by the committee provide inconsistent data about the relationship of sodium intake levels and kidney disease progression in patients with type 2 diabetes and macroalbuminuria, and some evidence suggests that low sodium intake may be
From page 112...
... Overall, the prospective cohort studies showed conflicting results for risk of gastric cancer and the case-control studies were potentially biased due to recall bias. Another possible effect modifier is infection with H
From page 113...
... The role of sodium intake in the risk of stone formation is not clear, and some authors suggest that while an increase in dietary sodium intake might increase urine calcium, it also might increase urine volume and decrease the urinary supersaturation of calcium oxalate (Eisner et al., 2009)
From page 114...
... 2007. Long term effects of dietary sodium reduction on cardiovascular disease outcomes: Observational follow-up of the trials of hypertension prevention (TOHP)
From page 115...
... 1991. Relative contributions of dietary sodium sources.
From page 116...
... 2009. Long-term effects of dietary sodium intake on cytokines and neu rohormonal activation in patients with recently compensated congestive heart failure.
From page 117...
... 2011. Fatal and nonfatal outcomes, incidence of hypertension, and blood pressure changes in relation to urinary sodium excretion.
From page 118...
... 2008. Relations between dietary sodium and potassium intakes and mortality from cardiovascular disease: The Japan Collaborative Cohort study for evaluation of cancer risks.


This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
More information on Chapter Skim is available.