Advice to reduce dietary salt for prevention of cardiovascular disease

Endothelial function is impaired after a high-salt meal in healthy subjects

BACKGROUND

Dietary salt is related to blood pressure (BP), and cardiovascular disease and increased sodium intakes have been shown to impair vascular function. The effect of salt on endothelial function postprandially is unknown.

OBJECTIVE

The aim was to investigate the postprandial effect of dietary salt on endothelial function as measured by flow-mediated dilatation (FMD) and peripheral arterial tonometry in healthy subjects.

DESIGN

Sixteen healthy, normotensive subjects received a meal with added salt (HSM; 65 mmol Na) and a control low-salt meal (LSM; 5 mmol Na) on 2 separate occasions in a randomized order. Endothelial function was measured while fasting and postprandially at 30, 60, 90, and 120 min by using FMD and reactive hyperemia peripheral arterial tonometry. BP was also measured.

RESULTS

Baseline FMD, reactive hyperemia index (RHI), and BP values were similar across interventions. Overall FMD was reduced 2 h postprandially. FMD was significantly more impaired after the HSM than after the LSM at 30 min [HSM (mean ± SD): 3.39 ± 2.44%; LSM: 6.05 ± 3.21%; P < 0.01] and at 60 min (HSM: 2.20 ± 2.77%; LSM: 4.64 ± 2.48%; P < 0.01). No significant differences in BP or RHI were observed between meals.

CONCLUSIONS

An HSM, which reflects the typical amount of salt consumed in a commonly eaten meal, can significantly suppress brachial artery FMD within 30 min. These results suggest that high salt intakes have acute adverse effects on vascular dilatation in the postprandial state. This trial was registered at www.anzctr.org.au/trial_view.aspx?ID=335115 as ACTRN12610000124033.

Evaluation of the Monell forced-choice, paired-comparison tracking procedure for determining sweet taste preferences across the lifespan

Lack of methodology to assess taste in children limits its measurement in research studies that include pediatric populations. We used the Monell 2-series, forced-choice tracking method to measure sucrose preferences of a racially/ethnically diverse sample (n = 949) of children, adolescents, and adults. Reliability was assessed by comparing the results of the first series with the second series. Validity was assessed by relating participants' sucrose preferences to their preferences for foods varying in sweetness. The task required, on average, 7 presentations of aqueous sucrose solution pairs. Children and adolescents preferred more concentrated sweetness than adults (P < 0.001). Black children/adolescents preferred a more concentrated sucrose solution than did White children/adolescents even when gender, parental education level, and family income were used as covariates. Data from a single series were sufficient to detect age-related differences but insufficient to detect racial/ethnic differences in sweet preferences. Level of sweetness preferred significantly correlated with the sugar content of favorite cereals (P < 0.001) and beverages (P < 0.02). This method is brief and has evidence of reliability and external validity. Although a single series will yield useful information about age-related differences in taste preferences, the 2-series version should be considered when differences in race/ethnicity are of interest.

Estimation of the burden of cardiovascular disease attributable to modifiable risk factors and cost-effectiveness analysis of preventative interventions to reduce this burden in Argentina

BACKGROUND

Cardiovascular disease (CVD) is the primary cause of mortality and morbidity in Argentina representing 34.2% of deaths and 12.6% of potential years of life lost (PYLL). The aim of the study was to estimate the burden of acute coronary heart disease (CHD) and stroke and the cost-effectiveness of preventative population-based and clinical interventions.

METHODS

An epidemiological model was built incorporating prevalence and distribution of high blood pressure, high cholesterol, hyperglycemia, overweight and obesity, smoking, and physical inactivity, obtained from the Argentine Survey of Risk Factors dataset. Population Attributable Fraction (PAF) of each risk factor was estimated using relative risks from international sources. Total fatal and non-fatal events, PYLL and Disability Adjusted Life Years (DALY) were estimated. Costs of event were calculated from local utilization databases and expressed in international dollars (I$). Incremental cost-effectiveness ratios (ICER) were estimated for six interventions: reducing salt in bread, mass media campaign to promote tobacco cessation, pharmacological therapy of high blood pressure, pharmacological therapy of high cholesterol, tobacco cessation therapy with bupropion, and a multidrug strategy for people with an estimated absolute risk > 20% in 10 years.

RESULTS

An estimated total of 611,635 DALY was lost due to acute CHD and stroke for 2005. Modifiable risk factors explained 71.1% of DALY and more than 80% of events. Two interventions were cost-saving: lowering salt intake in the population through reducing salt in bread and multidrug therapy targeted to persons with an absolute risk above 20% in 10 years; three interventions had very acceptable ICERs: drug therapy for high blood pressure in hypertensive patients not yet undergoing treatment (I$ 2,908 per DALY saved), mass media campaign to promote tobacco cessation amongst smokers (I$ 3,186 per DALY saved), and lowering cholesterol with statin drug therapy (I$ 14,432 per DALY saved); and one intervention was not found to be cost-effective: tobacco cessation with bupropion (I$ 59,433 per DALY saved)

CONCLUSIONS

Most of the interventions selected were cost-saving or very cost-effective. This study aims to inform policy makers on resource-allocation decisions to reduce the burden of CVD in Argentina.

Coronary mortality declines in the U.S. between 1980 and 2000 quantifying the contributions from primary and secondary prevention

BACKGROUND

Coronary heart disease (CHD) mortality rates in the U.S. have halved since 1980. However, CHD remains a leading cause of death. The relative importance of secondary and primary prevention in explaining falls in coronary heart disease mortality is debated.

PURPOSE

The aim of this study was to quantify the primary and secondary preventive contributions to the U.S. CHD mortality fall between 1980 and 2000.

METHODS

The IMPACT model was used to estimate contributions to the U.S. CHD mortality fall from risk factor declines in asymptomatic individuals (primary prevention) and in CHD patients (secondary prevention). Analyses were carried out in 2008.

RESULTS

Approximately 316,100 fewer deaths were attributable to risk factor declines: 64,930 in CHD patients (21%) and 251,170 in asymptomatic individuals (79%). Smoking declines accounted for approximately 8390 fewer deaths in CHD patients and for 46,315 fewer deaths in asymptomatic people. Cholesterol falls gave approximately 22,210 fewer deaths in CHD patients and 107,300 fewer deaths in asymptomatic people. Statins accounted for approximately 16,580 fewer deaths, that is, one sixth of this mortality fall. Systolic blood pressure declines accounted for approximately 34,330 fewer deaths among CHD patients and 97,555 fewer deaths in asymptomatic individuals. Antihypertensive medications accounted for approximately 23,845 fewer deaths.

CONCLUSIONS

Half of the U.S. mortality fall in coronary heart disease between 1980 and 2000 was attributable to risk factor declines, with primary prevention producing substantially larger mortality reductions than secondary.

The development and evaluation of a complex health education intervention for adults with a diagnosis of schizophrenia

Life expectancy in adults with schizophrenia is reduced by approximately 15 years compared with others in the population. Two thirds of premature deaths result from natural causes triggered by unhealthy lifestyles and the side-effects of antipsychotic medication. There is a need to develop and evaluate health education interventions for people with this diagnosis. In this paper we describe how with reference to the UK Medical Research Council's complex interventions framework we developed and evaluated a health education intervention designed specifically for adults with schizophrenia. The study was completed in three separate but interrelated phases: (1) theoretical work was undertaken to identify the components of effective health education interventions; (2) this information was synthesized to develop the intervention; and (3) the intervention was tested in an open exploratory trial which used mixed methods to evaluate the feasibility, acceptability and potential effect of the intervention. 45 service users were referred, 39 attended the groups and 65% attended at least half of the sessions. Participants reported significant increases in their consumption of fruit and vegetables and levels of physical activity. Results suggest that this model of health education is feasible and acceptable for this population and that it shows promise in supporting health-related behaviour changes.

Salt restriction for the prevention of cardiovascular disease

BACKGROUND

Restricting the dietary intake of sodium chloride is associated with a reduction of the arterial blood pressure by approximately 4/2 mm Hg in hypertensive patients and by approximately 1/0.6 mm Hg in normotensive persons. As the cardiovascular risk is known to rise steadily with systolic blood pressure values starting from 115 mm Hg, lowering the mean blood pressure of the general population by dietary salt restriction would seem to be a practicable form of primary prevention of cardiovascular disease.

METHOD

Selective literature search and review.

RESULTS

Multiple studies have shown dietary salt restriction to be associated with lower cardiovascular morbidity and mortality. The reduction of adjusted relative risk in controlled observational studies ranges from 25% over 15 years to 41% over three years.

CONCLUSION

On the basis of the available studies, it seems likely that a moderate lowering of the daily intake of sodium chloride by the general population from 8 to 12 grams per day (the current value) to 5 to 6 grams per day would be a useful public health measure, with economic benefits as well. The potential risks for certain groups of individuals are foreseeable and controllable. A general reduction of dietary salt intake can only be achieved by reducing the sodium chloride content of industrially processed foods, as these account for 75% to 80% of the sodium chloride consumed daily. Aside from a general reduction of dietary salt intake, further important primary prevention measures for the general population include changes in lifestyle and in dietary habits.

Organic acid bioavailability from banana and sweet potato using an in vitro digestion and Caco-2 cell model

INTRODUCTION

Organic acids from plant food have been shown to play an important role in the prevention of chronic diseases (osteoporosis, obesity), inherent to western diets, but little is known about their bioavailability in the small intestine, information that needs to be determined in order to quantify likely effects on human health.

METHODS

An in vitro model of human digestion was carried out, comprising simulated oral, gastric and pancreatic digestion followed by an in vitro model of small intestine absorption using Caco-2 cell monolayers. As models for fruits and vegetables, freeze-dried or raw samples of banana and sweet potato were used.

RESULTS

Organic acids have been found to be slowly released from the food matrix during simulated digestion of both banana and sweet potato, either raw or after freeze-drying. In the Caco-2 cell assay, malic and oxalic acids were absorbed more than citric acid. Oxalic and citric acids, but not malic acid, were transported across the cell monolayer. The release and uptake of major organic acids from model fruits and vegetables using established in vitro simulation processes was not quantitative and varied with acid type.

CONCLUSION

Partial uptake is consistent with a dual nutritional role for organic acids as alkalinising agents (fraction which is taken up) and as modulators of large intestinal function (fraction which is not taken up in the small intestine). Studies of in vivo digestive release and uptake are needed in order to identify the contribution of organic acids to the nutritional value of fruits and vegetables.

Improving physical activity and dietary behaviours with single or multiple health behaviour interventions? A synthesis of meta-analyses and reviews

Since multiple health behaviour interventions have gained popularity, it is important to investigate their effectiveness compared to single health behaviour interventions. This synthesis aims to determine whether single intervention (physical activity or dietary) or multiple interventions (physical activity and dietary) are more effective at increasing these behaviours by synthesizing reviews and meta-analyses. A sub-purpose also explored their impact on weight. Overall, reviews/meta-analyses showed that single health behaviour interventions were more effective at increasing the targeted behaviours, while multiple health behaviour interventions resulted in greater weight loss. This review may assist policies aiming at improving physical activity and nutrition and reversing the obesity epidemic.

Projected effect of dietary salt reductions on future cardiovascular disease

BACKGROUND

The U.S. diet is high in salt, with the majority coming from processed foods. Reducing dietary salt is a potentially important target for the improvement of public health.

METHODS

We used the Coronary Heart Disease (CHD) Policy Model to quantify the benefits of potentially achievable, population-wide reductions in dietary salt of up to 3 g per day (1200 mg of sodium per day). We estimated the rates and costs of cardiovascular disease in subgroups defined by age, sex, and race; compared the effects of salt reduction with those of other interventions intended to reduce the risk of cardiovascular disease; and determined the cost-effectiveness of salt reduction as compared with the treatment of hypertension with medications.

RESULTS

Reducing dietary salt by 3 g per day is projected to reduce the annual number of new cases of CHD by 60,000 to 120,000, stroke by 32,000 to 66,000, and myocardial infarction by 54,000 to 99,000 and to reduce the annual number of deaths from any cause by 44,000 to 92,000. All segments of the population would benefit, with blacks benefiting proportionately more, women benefiting particularly from stroke reduction, older adults from reductions in CHD events, and younger adults from lower mortality rates. The cardiovascular benefits of reduced salt intake are on par with the benefits of population-wide reductions in tobacco use, obesity, and cholesterol levels. A regulatory intervention designed to achieve a reduction in salt intake of 3 g per day would save 194,000 to 392,000 quality-adjusted life-years and $10 billion to $24 billion in health care costs annually. Such an intervention would be cost-saving even if only a modest reduction of 1 g per day were achieved gradually between 2010 and 2019 and would be more cost-effective than using medications to lower blood pressure in all persons with hypertension.

CONCLUSIONS

Modest reductions in dietary salt could substantially reduce cardiovascular events and medical costs and should be a public health target.

Community-based Randomized Controlled Trial of Non-pharmacological Interventions in Prevention and Control of Hypertension among Young Adults

CONTEXT

Hypertension is a major chronic lifestyle disease. Several non-pharmacological interventions are effective in bringing down the blood pressure (BP). This study focuses on the effectiveness of such interventions among young adults.

AIMS

To measure the efficacy of physical exercise, reduction in salt intake, and yoga, in lowering BP among young (20-25) pre-hypertensives and hypertensives, and to compare their relative efficacies.

SETTINGS AND DESIGN

The study was done in the urban service area of JIPMER. Pre-hypertensives and hypertensives, identified from previous studies, constituted the universe. The participants were randomized into one control and three interventional groups.

MATERIALS AND METHODS

A total of 113 subjects: 30, 28, 28 and 27 in four groups respectively participated for eight weeks: control (I), physical exercise (II) - brisk walking for 50-60 minutes, four days/week, salt intake reduction (III) - to at least half of their previous intake, and practice of yoga (IV) - for 30-45 minutes/day on at least five days/week.

STATISTICAL ANALYSIS USED

Efficacy was assessed using paired t test and ANOVA with Games Howell post hoc test. An intention to treat analysis was also performed.

RESULTS

A total of 102 participants (29, 27, 25 and 21 in groups I, II, III and IV) completed the study. All three intervention groups showed a significant reduction in BP (SBP/DBP: 5.3/6.0 in group II, 2.6/3.7 in III, and 2.0/2.6 mm Hg in IV respectively). There was no significant change (SBP/DBP: 0.2/0.5 mmHg) of BP in control group (I). Physical exercise was most effective (considered individually); salt intake reduction and yoga were also effective.

CONCLUSIONS

Physical exercise, salt intake reduction, and yoga are effective non-pharmacological interventions in significantly reducing BP among young hypertensives and pre-hypertensives. These can therefore be positively recommended for hypertensives. There is also a case to deploy these interventions in the general population.

Review of cardiovascular risk factors in women

BACKGROUND

Although cardiovascular disease (CVD) is the leading cause of death in women in the United States, a knowledge gap persists regarding the mechanisms and management of CVD in women. Before treatment can be optimized, the role of cardiovascular risk factors must be elucidated.

OBJECTIVE

This review provides an updated assessment of cardiovascular risk factors in women, with a focus on cardiometabolic risk.

METHODS

MEDLINE and Cochrane Library databases, and statistics from the National Health and Nutrition Examination Survey and the American Heart Association, were searched from 1990 to September 2008 using the following terms: cardiovascular risk factors, women, gender, cardiometabolic risk, abdominal obesity, and metabolic syndrome. Publications were classified as English-only original data, reviews, and clinical guidelines. Nonpublished data were excluded. Data were extracted by 2 reviewers independently.

RESULTS

Investigators performing multivariable predictive models have estimated that traditional risk factors account for approximately 70% of the variance in estimating cardiovascular events. However, substantial sex differences exist in the prevalence of traditional risk factors as well as in cardiovascular outcomes. Hypertension is more prevalent in men until the age of 59 years, but then contributes to greater morbidity in older women. Low levels of high-density lipoprotein and elevated triglyceride levels pose more of a threat to women, yet high levels of low-density lipoprotein pose equal risk for women and men. The CVD mortality rate is -3 times greater in people with diabetes than in those without diabetes. Among diabetic individuals, CVD mortality is slightly higher in women compared with men.

CONCLUSIONS

Increased knowledge of gender-specific risks for CVD has led to national campaigns to educate women. In addition to traditional risk factors, cardiometabolic risk is an important consideration in women. Controversy exists regarding the exact definitions and usefulness of the term metabolic syndrome, but it is clear that the presence of certain factors contributes to increased morbidity and mortality in affected individuals. Abdominal obesity links insulin resistance, dyslipidemia, and hypertension through complex endocrine pathways. Current research is identifying gene x gender interactions, and continued research is necessary to explore the relationship of sex steroids and cardiovascular risk in both men and women.

Salt restriction among hypertensive patients: modest blood pressure effect and no adverse effects

OBJECTIVE

Previous studies, mainly evaluating short-term very low salt diets, suggest that salt restriction may influence glucose and insulin metabolism, catecholamines, renin, aldosterone, and lipid levels adversely. The authors wanted to explore whether sodium restriction for eight weeks influenced insulin secretion unfavourably, and evaluate the efficacy and safety of such treatment also in terms of other parameters important in the management of hypertensive patients.

DESIGN

A double-blind randomized controlled parallel group designed trial. All participants received dietary advice aimed at a moderate salt-restricted diet. Half of the participants received salt capsules, the others received identical placebo capsules.

SETTING

General practice.

SUBJECTS

Forty-six hypertensive patients inadequately controlled by drug treatment.

MAIN OUTCOME MEASURES

Fasting serum insulin C-peptide and glucose and levels of these measures after oral glucose, blood pressure, serum aldosterone and lipids, peripheral resistance, and skin conductance.

RESULTS

Salt restriction did not influence glucose and insulin metabolism, aldosterone, or lipid levels adversely. We observed better blood pressure regulation in the low salt group than in the high salt group, with a systolic and diastolic blood pressure difference of 5/5 mmHg after eight weeks. The difference was only statistically significant for diastolic blood pressure, p 0.02.

CONCLUSION

This study revealed a modest diastolic blood pressure reducing effect of moderate sodium restriction. This reduction was obtained without any apparent unfavourable side effects such as increased insulin secretion, impaired glucose tolerance or dyslipidaemia.

Sodium intake and mortality follow-up in the Third National Health and Nutrition Examination Survey (NHANES III)

BACKGROUND

Sodium restriction is commonly recommended as a measure to lower blood pressure and thus reduce cardiovascular disease (CVD) and all-cause mortality. However, some studies have observed higher mortality associated with lower sodium intake.

OBJECTIVE

To test the hypothesis that lower sodium is associated with subsequent higher cardiovascular disease (CVD) and all cause mortality in the Third National Health and Nutrition Examination Survey (NHANES III).

DESIGN

Observational cohort study of mortality subsequent to a baseline survey.

PARTICIPANTS

Representative sample (n = 8,699) of non-institutionalized US adults age > or = 30, without history of CVD events, recruited between 1988-1994.

MEASUREMENTS AND MAIN RESULTS

Dietary sodium and calorie intakes estimated from a single baseline 24-h dietary recall. Vital status and cause of death were obtained from the National Death Index through the year 2000. Hazard ratio (HR) for CVD mortality of lowest to highest quartile of sodium, adjusted for calories and other CVD risk factors, in a Cox model, was 1.80 (95% CI 1.05, 3.08, p = 0.03). Non-significant trends of an inverse association of continuous sodium (per 1,000 mg) intake with CVD and all-cause mortality were observed with a 99% CI of 0.73, 1.06 (p = 0.07) and 0.86, 1.04 (p = 0.11), respectively, while trends for a direct association were not observed.

CONCLUSION

Observed associations of lower sodium with higher mortality were modest and mostly not statistically significant. However, these findings also suggest that for the general US adult population, higher sodium is unlikely to be independently associated with higher CVD or all-cause mortality.

Chronic disease prevention: health effects and financial costs of strategies to reduce salt intake and control tobacco use

In 2005, WHO set a global goal to reduce rates of death from chronic (non-communicable) disease by an additional 2% every year. To this end, we investigated how many deaths could potentially be averted over 10 years by implementation of selected population-based interventions, and calculated the financial costs of their implementation. We selected two interventions: to reduce salt intake in the population by 15% and to implement four key elements of the WHO Framework Convention on Tobacco Control (FCTC). We used methods from the WHO Comparative Risk Assessment project to estimate shifts in the distribution of risk factors associated with salt intake and tobacco use, and to model the effects on chronic disease mortality for 23 countries that account for 80% of chronic disease burden in the developing world. We showed that, over 10 years (2006-2015), 13.8 million deaths could be averted by implementation of these interventions, at a cost of less than US$0.40 per person per year in low-income and lower middle-income countries, and US$0.50-1.00 per person per year in upper middle-income countries (as of 2005). These two population-based intervention strategies could therefore substantially reduce mortality from chronic diseases, and make a major (and affordable) contribution towards achievement of the global goal to prevent and control chronic diseases.

Dietary advice for reducing cardiovascular risk

BACKGROUND

Changes in population diet are likely to reduce cardiovascular disease and cancer, but the effect of dietary advice is uncertain.

OBJECTIVES

To assess the effects of providing dietary advice to achieve sustained dietary changes or improved cardiovascular risk profile among healthy adults.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials, DARE and HTA databases on The Cochrane Library (Issue 4 2006), MEDLINE (1966 to December 2000, 2004 to November 2006) and EMBASE (1985 to December 2000, 2005 to November 2006). Additional searches were done on CAB Health (1972 to December 1999), CVRCT registry (2000), CCT (2000) and SIGLE (1980 to 2000). Dissertation abstracts and reference lists of articles were checked and researchers were contacted.

SELECTION CRITERIA

Randomised studies with no more than 20% loss to follow-up, lasting at least 3 months involving healthy adults comparing dietary advice with no advice or minimal advice. Trials involving children, trials to reduce weight or those involving supplementation were excluded.

DATA COLLECTION AND ANALYSIS

Two reviewers independently assessed trial quality and extracted data. Study authors were contacted for additional information.

MAIN RESULTS

Thirty-eight trials with 46 intervention arms (comparisons) comparing dietary advice with no advice were included in the review. 17,871 participants/clusters were randomised. Twenty-six of the 38 included trials were conducted in the USA. Dietary advice reduced total serum cholesterol by 0.16 mmol/L (95% CI 0.06 to 0.25) and LDL cholesterol by 0.18 mmol/L (95% CI 0.1 to 0.27) after 3-24 months. Mean HDL cholesterol levels and triglyceride levels were unchanged. Dietary advice reduced blood pressure by 2.07 mmHg systolic (95% CI 0.95 to 3.19) and 1.15 mmHg diastolic (95% CI 0.48 to 1.85) and 24-hour urinary sodium excretion by 44.2 mmol (95% CI 33.6 to 54.7) after 3-36 months. Three trials reported plasma antioxidants where small increases were seen in lutein and beta-cryptoxanthin, but there was heterogeneity in the trial effects. Self-reported dietary intake may be subject to reporting bias, and there was significant heterogeneity in all the following analyses. Compared to no advice, dietary advice increased fruit and vegetable intake by 1.25 servings/day (95% CI 0.7 to 1.81). Dietary fibre intake increased with advice by 5.99 g/day (95% CI 1.12 to 10.86), while total dietary fat as a percentage of total energy intake fell by 4.49 % (95% CI 2.31 to 6.66) with dietary advice and saturated fat intake fell by 2.36 % (95% CI 1.32 to 3.39).

AUTHORS' CONCLUSIONS

Dietary advice appears to be effective in bringing about modest beneficial changes in diet and cardiovascular risk factors over approximately 10 months but longer term effects are not known.

Ethnicity and cardiovascular disease prevention in the United Kingdom: a practical approach to management

The United Kingdom is a diverse society with 7.9% of the population from black and minority ethnic groups (BMEGs). The causes of the excess cardiovascular disease (CVD) and stroke morbidity and mortality in BMEGs are incompletely understood though socio-economic factors are important. However, the role of classical cardiovascular (CV) risk factors is clearly important despite the patterns of these risk factors varying significantly by ethnic group. Despite the major burden of CVD and stroke among BMEGs in the UK, the majority of the evidence on the management of such conditions has been based on predominantly white European populations. Moreover, the CV epidemiology of African Americans does not represent well the morbidity and mortality experience seen in black Africans and black Caribbeans, both in Britain and in their native African countries. In particular, atherosclerotic disease and coronary heart disease are still relatively rare in the latter groups. This is unlike the South Asian diaspora, who have prevalence rates of CVD in epidemic proportions both in the diaspora and on the subcontinent. As the BMEGs have been under-represented in research, a multitude of guidelines exists for the 'general population.' However, specific reference and recommendation on primary and secondary prevention guidelines in relation to ethnic groups is extremely limited. This document provides an overview of ethnicity and CVD in the United Kingdom, with management recommendations based on a roundtable discussion of a multidisciplinary ethnicity and CVD consensus group, all of whom have an academic interest and clinical practice in a multiethnic community.

Sodium intake and mortality in the NHANES II follow-up study

PURPOSE

US Dietary Guidelines recommend a daily sodium intake <2300 mg, but evidence linking sodium intake to mortality outcomes is scant and inconsistent. To assess the association of sodium intake with cardiovascular disease (CVD) and all-cause mortality and the potential impact of dietary sodium intake <2300 mg, we examined data from the Second National Health and Nutrition Examination Survey (NHANES II).

METHODS

Observational cohort study linking sodium, estimated by single 24-hour dietary recall and adjusted for calorie intake, in a community sample (n = 7154) representing 78.9 million non-institutionalized US adults (ages 30-74). Hazard ratios (HR) for CVD and all-cause mortality were calculated from multivariable adjusted Cox models accounting for the sampling design.

RESULTS

Over mean 13.7 (range: 0.5-16.8) years follow-up, there were 1343 deaths (541 CVD). Sodium (adjusted for calories) and sodium/calorie ratio as continuous variables had independent inverse associations with CVD mortality (P = .03 and P = .008, respectively). Adjusted HR of CVD mortality for sodium <2300 mg was 1.37 (95% confidence interval [CI]: 1.03-1.81, P = .033), and 1.28 (95% CI: 1.10-1.50, P = .003) for all-cause mortality. Alternate sodium thresholds from 1900-2700 mg gave similar results. Results were consistent in the majority of subgroups examined, but no such associations were observed for those <55 years old, non-whites, or the obese.

CONCLUSION

The inverse association of sodium to CVD mortality seen here raises questions regarding the likelihood of a survival advantage accompanying a lower sodium diet. These findings highlight the need for further study of the relation of dietary sodium to mortality outcomes.

Hypertension

For primary care physicians, managing hypertension is a challenging undertaking because it is a good example of the balance be-tween implementing evidence and working with patients' beliefs, ideas, and resources to help them improve their health. In this article the authors review the evidence supporting aggressive recommendations on prevention and treatment of hypertension to decrease cardiovascular, cerebrovascular, and renal disease. They review the public health implications of hypertension, but focus on the challenges clinicians face in working with patients to optimize their health with the financial and personal resources they have available.

Randomized controlled trial: effect of nutritional counselling in general practice

OBJECTIVES

To investigate the effectiveness of a non-structured 15-min educational intervention by general practitioners (GPs) on modifications of daily diet among healthy adults.

DESIGN

Two arms randomized trial lasting 12 months.

SETTING

Italian general practitioner wards. Subjects A total of 3,186 men and women aged 18-65 years recruited in the medical ward by their GPs.

INTERVENTIONS

An educational intervention and a brochure on the basics of a healthy diet based on the Italian Guidelines for a Correct Nutrition, 1998. The main study goal was to attain an intake of fruits and vegetables >5 servings per day. Follow-up visit every 6 months. Main outcome measures Weight, blood pressure, and a 40-items Food Frequency Questionnaire.

RESULTS

The intervention group showed a slightly reduced net intake of meat and a slightly increased net intake of fruits and vegetables, fish products, and olive oil. Body mass index (BMI) changed only in the treatment arm [-0.41 95% confidence interval (95% CI) -0.11 to -0.53]. The net change at 1 year in the intervention arm was +1.31 (CI 0.90-4.39) for fruits and vegetables, and -0.22 (-0.11 to -0.69) for meat (portions per week). We also computed a 'healthy diet score' reflecting compliance with recommended dietary habits. In the intervention group, the mean score at recruitment was significantly lower than the mean score at the end of follow-up (Crude score change = 0.29; CI 0.19-0.48). No differences were observed in the control group (Crude score change = -0.04; CI -0.22-0.02). The difference in score from baseline to the final visit, comparing the intervention vs the control group, was statistically significant (P < 0.001) (MANOVA adjusted by sex, BMI, education, and time).

CONCLUSIONS

A brief educational intervention by GPs can induce multiple diet changes that may lower BMI and potentially reduce chronic disease risk in generally healthy adults.

Hypertension management: the primary care nursing role

Hypertension is a prevalent chronic illness that is implicated in many cardiovascular diseases. Practice nurses and the district nursing team have a major role to play in its management. In this article, current British Hypertension Society guidelines are presented and discussed with regards to their evidence base. Implications for nursing practice are highlighted.

Current Treatment Options for the Metabolic Syndrome

The metabolic syndrome is defined as a condition characterized by a set of clinical criteria: insulin resistance, visceral obesity, atherogenic dyslipidemia, and hypertension. The major risk factors leading to the epidemic of this syndrome in the United States are visceral obesity, physical inactivity, and an atherogenic diet. The available current evidence suggests that the first step in management of patients with metabolic syndrome should be focused on lifestyle modifications (eg, weight loss and physical activity). The treatment should be based on two major components: behavioral change to reduce caloric intake and an increase in physical activity. A realistic goal for weight reduction should be 7% to 10% over 6 to 12 months. The general dietary recommendations include low intake of saturated fats, trans fats and cholesterol, and diets with low glycemic index. Soy protein could be more beneficial than animal protein in weight reduction and correction of dyslipidemia. Physical activity is associated with successful weight reduction and these therapeutic lifestyle changes can reduce by half the progression to new-onset diabetes in patients with metabolic syndrome. Physical activity recommendations should include practical, regular, and moderated regimens of exercise, with a daily minimum of 30 to 60 minutes. An equal balance between aerobic exercise and strength training is advised. Medication therapy is a critical step in the management of patients with metabolic syndrome when lifestyle modifications fail to achieve the therapeutic goals. There is no single best therapy and the treatment should consist of treatment of individual component(s). Atherogenic dyslipidemia should be controlled with statins if there is concomitant increase in low-density lipoprotein cholesterol and if indicated with combination therapy, including fibrates, nicotinic acid, bile acid-binding resins, or ezetimibe. Drugs such as thiazolidinediones and renin-angiotensin system blockers are a few of the available agents in this category. Some evidence suggests that angiotensin-converting enzyme inhibitors and b blockers are more beneficial for treatment of hypertension in patients with metabolic syndrome. Patients with metabolic syndrome also have elevations in fibrinogen and other coagulation factors leading to prothrombotic state and aspirin may be beneficial for primary prevention in these patients. The new developments in the treatment of metabolic syndrome with drugs, such as peroxisome proliferator-activated receptor agonists, will broaden the horizons of the current treatment options in metabolic syndrome.