Effects of dietary patterns on blood pressure: subgroup analysis of the Dietary Approaches to Stop Hypertension (DASH) randomized clinical trial

State of the Art Reviews: Relationship Between Diet/ Physical Activity and Health

Obesity and 4 of the leading causes of death—heart disease, cancer, stroke, and type 2 diabetes mellitus—are related to lifestyle. The combination of a healthy weight, prudent diet, and daily physical activity clearly plays a role in primary, secondary, and tertiary prevention of these and other chronic diseases. Because nearly 65% of the adult population is overweight or obese, weight loss and maintenance are central to this review article. Improved lipid profiles, blood pressure, insulin sensitivity, and euglycemia are associated with weight loss or a normal body weight; thus, maintaining a healthy weight is a universal recommendation for health. The methods for improving lifestyle described in the section on obesity include assessing nutritional status and stages of change of the client, setting realistic goals, eating a diet high in fruits and vegetables with low-fat sources of dairy and protein, and achieving appropriate physical activity levels. The importance of physicians discussing weight with clients and vice versa is stressed. The common features of lifestyle-related diseases make them amenable to similar lifestyle interventions.

Nutrition Interventions for Cardiovascular Disease

Nutrition therapy is effective at controlling cardiovascular disease risk factors and therefore reducing cardiovascular disease risk. Physicians should play an active role in providing nutrition interventions for patients who would benefit from cardiovascular disease risk reduction or refer them to other professionals as needed. The evidence on nutrition interventions for blood pressure and lipid control, including overall dietary patterns, dietary fat and macronutrients, dietary cholesterol, sodium, and alcohol intake, is discussed.

Dietary Habits and Risk of Kidney Function Decline in an Urban Population

OBJECTIVE

Explore the association between following a Dietary Approaches to Stop Hypertension (DASH)-accordant diet and kidney end points among urban adults.

DESIGN

Prospective cohort study.

SETTING

Healthy Aging in Neighborhoods of Diversity across the Life Span study.

SUBJECTS

A total of 1,534 urban dwelling participants of the Healthy Aging in Neighborhoods of Diversity across the Life Span study with a baseline estimated glomerular filtration rate (eGFR) ≥60 mL/minute/1.73 m².

INTERVENTION

DASH diet accordance determined via a score based on nine target nutrients.

MAIN OUTCOME MEASURE

Rapid kidney function decline (eGFR decline >3 mL/minute/1.73 m² per year), incident chronic kidney disease (CKD) (follow-up eGFR <60 mL/minute/1.73 m²), and eGFR decline >25%.

RESULTS

Participants' mean age was 48 years, and 59% were African-American. Median DASH score was 1.5 (range, 0-8). Over a median of 5 years, 13.4% experienced rapid eGFR decline, including 15.2% among participants not following a DASH-accordant diet (score ≤1) and 12.0% with higher accordance (score >1) (P = .08). Outcomes varied by hypertension status. In multinomial logistic regression models, following adjustment for sociodemographic and clinical factors, including total energy intake, low DASH diet accordance was associated with rapid eGFR decline among participants with hypertension (risk ratio, 1.68; 95% confidence interval: 1.17-2.42) but not among those without hypertension (risk ratio, 0.83; 95% confidence interval: 0.56-1.24; P interaction .001). There was no statistically significant association between DASH diet accordance and incident CKD or eGFR decline >25%. Results were similar when DASH diet accordance was analyzed in tertiles.

CONCLUSIONS

Among urban adults, low accordance to a DASH-type diet was not associated with incident CKD, but was associated with higher risk of rapid eGFR decline among those with hypertension, yet not among those without hypertension. Further study of dietary patterns as a potential target for improving kidney outcomes among high-risk populations is warranted.

Potassium Intake, Bioavailability, Hypertension, and Glucose Control

Potassium is an essential nutrient. It is the most abundant cation in intracellular fluid where it plays a key role in maintaining cell function. The gradient of potassium across the cell membrane determines cellular membrane potential, which is maintained in large part by the ubiquitous ion channel the sodium-potassium (Na+-K+) ATPase pump. Approximately 90% of potassium consumed (60–100 mEq) is lost in the urine, with the other 10% excreted in the stool, and a very small amount lost in sweat. Little is known about the bioavailability of potassium, especially from dietary sources. Less is understood on how bioavailability may affect health outcomes. Hypertension (HTN) is the leading cause of cardiovascular disease (CVD) and a major financial burden ($50.6 billion) to the US public health system, and has a significant impact on all-cause morbidity and mortality worldwide. The relationship between increased potassium supplementation and a decrease in HTN is relatively well understood, but the effect of increased potassium intake from dietary sources on blood pressure overall is less clear. In addition, treatment options for hypertensive individuals (e.g., thiazide diuretics) may further compound chronic disease risk via impairments in potassium utilization and glucose control. Understanding potassium bioavailability from various sources may help to reveal how specific compounds and tissues influence potassium movement, and further the understanding of its role in health.

Nutrition and Cardiovascular Disease: Finding the Perfect Recipe for Cardiovascular Health

The increasing burden of cardiovascular disease (CVD) despite the progress in management entails the need of more effective preventive and curative strategies. As dietary-associated risk is the most important behavioral factor influencing global health, it appears the best target in the challenge against CVD. Although for many years, since the formulation of the cholesterol hypothesis, a nutrient-based approach was attempted for CVD prevention and treatment, in recent years a dietary-based approach resulted more effective in reducing cardiovascular risk worldwide. After the publication of randomized trials on the remarkable effects of the Mediterranean diet and the Dietary Approach to Stop Hypertension (DASH) diet on CVD, new efforts were put on research about the effects of complex dietary interventions on CVD. The purpose of this paper is to review the evidence on dietary interventions in the prevention and disease modification of CVD, focusing on coronary artery disease and heart failure, the main disease responsible for the enormous toll taken by CVD worldwide.

Concordance with DASH diet and blood pressure change: results from the Framingham Offspring Study (1991-2008)

BACKGROUND

Concordance with the Dietary Approaches to Stop Hypertension (DASH) diet has been shown to reduce blood pressure (BP) in short-term intervention studies, but long-term effects are unclear. We evaluated the association of DASH diet concordance with BP trajectories and incidence of hypertension, in 2187 men and women (mean age 52.5 years at baseline) participating in the Framingham Offspring cohort.

METHOD

Diet and BP were assessed from 1991 to 2008, with a median follow-up time of 13.4 years. DASH scores (ranging from 0 for worst to 10 for best concordance with DASH diet) were calculated by summing 10 food components that comprise the DASH diet pattern, including fruits and vegetables, low-fat dairy products, lean meat, and plant-based protein. Mixed-effect and Cox regression models were applied, to assess the association of DASH diet concordance with BP longitudinal change and with incidence of hypertension, respectively. All analyses were adjusted for age, sex, smoking status, history of diabetes, BMI, and physical activity.

RESULT

Overall, SBP increased by 0.34 mmHg and DBP by 0.10 mmHg annually, in the Framingham Offspring cohort. Every unit increase in the DASH score resulted in a modest increase in SBP of 0.054 mmHg/year (P = 0.028). No associations were observed between DASH diet concordance and DBP or incidence of hypertension.

CONCLUSION

Long-term concordance with the DASH diet was not associated with a decreasing BP trajectory over time, or with decreased incidence of hypertension, in this population of middle-aged adults.

The effect of dietary approaches to stop hypertension (DASH) diet on weight and body composition in adults: a systematic review and meta-analysis of randomized controlled clinical trials

BACKGROUND

Dietary approaches to stop hypertension (DASH) diet is rich in foods that are proposed to be inversely associated with obesity. Therefore, DASH might better affect body weight; however, published data are conflicting.

OBJECTIVE

To assess the effect of DASH on body weight and composition in adults.

METHODS

PubMed, EMBASE, Scopus and Google scholar were searched up to December 2015, for relevant randomized controlled clinical trials. Mean changes in body weight, body mass index (BMI) and waist circumference (WC) were extracted.

RESULTS

Thirteen articles (ten for body weight, six for BMI and two for WC) were eligible. Meta-analysis revealed that adults on DASH diet lose more weight (weighted mean difference [WMD] = -1.42 kg, 95% confidence interval [95%CI]: -2.03, -0.82) in 8-24 weeks, BMI (WMD = -0.42 kg m(-2) , 95%CI: -0.64, -0.20) in 8-52 weeks and WC (WMD = -1.05 cm, 95%CI: -1.61, -0.49) in 24 weeks compared with controls. Low caloric DASH led to even more weight reduction when compared with other low-energy diets. In addition, the effect was greater in overweight/obese participants and when compared with typical (Western or population's usual) diets.

CONCLUSION

DASH diet is a good choice for weight management particularly for weight reduction in overweight and obese participants.

Identification of dietary patterns associated with blood pressure in a sample of overweight Australian adults

The dietary approaches to stop hypertension (DASH) diet provides strong evidence for an optimal dietary pattern for blood pressure (BP) control; however, investigation at the level of key foods in a dietary pattern is sparse. This study aimed to assess the relationship between dietary patterns driven by key foods with BP in a sample of obese Australian adults. Secondary analysis was conducted on baseline data of 118 participants (45.1±8.4 years, mean BP=124.1±15.8/72.6±9.2 mm Hg) recruited in a weight reduction randomized controlled trial (ACTRN12608000425392). Dietary assessment was by a validated diet history interview. The average of three office BP measurements was taken. Factor analysis extracted dietary patterns and their relation to systolic BP (SBP) and diastolic BP (DBP) was analysed using multiple linear regression. Eight dietary patterns were identified based on leading foods: meat and alcohol; seafood; fats; fruits and nuts; legumes; confectionery; sweet foods; and yeast extracts and seasonings. A lower SBP was associated with alignment with the fruit and nuts pattern (β=-4.1 (95% confidence interval -7.5 to -0.7) mm Hg) and with seafood for DBP (β=-2.4 (-4.6 to -0.3) mm Hg). SBP and DBP were higher with yeast extract and seasonings (β=4.3 (1.4-7.3); 2.5 (0.9-4.0) mm Hg, respectively). In obese adults attending for weight loss, dietary patterns that included larger amounts of fruits and nuts and/or seafood were associated with lower BP at baseline, whereas patterns that were characterised by yeast extract and seasonings were associated with higher BP.

Exploratory serum fatty acid patterns associated with blood pressure in community-dwelling middle-aged and elderly Chinese

Background

Epidemiological studies have assessed relationships between circulating levels of fatty acid (FA) and blood pressure (BP), and their results remain controversial. Nevertheless, data are sparse on serum FA as biomarker and BP in China. The aim of the study was to investigate the association between serum FA and BP in Chinese populations.

Methods

We conducted a cross-sectional study nested within a community-based cohort of 2447 Chinese participants aged 35–79 years who completed a baseline assessment between October 2012 and April 2013. Baseline assessment included the collection of fasting blood samples, anthropometric measurements and a personal interview using a validated questionnaire. Serum FA was determined by gas-liquid chromatography. Exploratory factor analyses were employed to identify FA-factor as a reflection of serum FA pattern. A multiple regression model was conducted to estimate adjusted mean of BP with 95 % confidence interval (CI) by tertile groups of the generated FA-factor scores.

Results

Hypertensive patients have significantly higher serum 14:0, 16:0, 16:1n-7, 18:3n-6, 20:3n-6 and Δ⁶-desaturase index (18:3n-6/18:2n-6) as well as lower 18:2n-6, 22:6n-3 and Δ⁵-desaturase index (20:4n-6/20:3n-6) compared with normotensive participants. Factor 1 (low linoleic acid/high saturated FA pattern: 14:0, 16:0, 16:1n-7, 18:2n-6, 18:3n-6, 20:3n-6) and Factor 2 (n-3 PUFA pattern: 20:5n-3, 22:5n-3, 22:6n-3, 18:1n-9) were identified as indicators of the serum FA pattern. After adjustment for age, gender, body mass index, hypertension treatment, smoking, alcohol intake, education, profession, exercise habit, salt intake, family history of hypertension, heart rate, blood lipids and fasting blood-glucose levels, per a standard deviation (SD) increment of Factor 1 scores was associated with an increment of 2.44 (95 % CI: 1.73, 3.15) mm Hg for systolic BP, whereas per a SD increment of Factor 2 scores was associated with a reduction of 1.40 (95 % CI: 0.80, 2.04) mm Hg for diastolic BP.

Conclusions

The serum FA pattern characterized by low proportions of 14:0, 16:0, 16:1n-7 and 18:3n-6 as well as high 18:2n-6 and 22:6n-3 was beneficially associated with BP levels in this Chinese population. This evidence well supports the current dietary recommendations in the communities to replace saturated fat with polyunsaturated fat.

Electronic supplementary material

The online version of this article (doi:10.1186/s12944-016-0226-3) contains supplementary material, which is available to authorized users.

Food groups associated with a reduced risk of 15-year all-cause death

BACKGROUND/OBJECTIVES

Long-term observational cohorts provide the opportunity to investigate the potential impact of dietary patterns on death. We aimed to investigate all-cause death according to the consumption of selected food groups, and then to identify those independently associated with reduced mortality.

SUBJECTS/METHODS

Population survey of middle-aged men randomly selected in the period 1995-1997 from the general population of three French areas and followed over a median of 14.8 years. Dietary data were collected through a 3-day food record. Cox modeling was used to assess the risk of death according to selected foods groups after extensive adjustment for confounders, including a diet quality index.

RESULTS

The study population comprised 960 men (mean age 55.5 ±6.2 years). After a median follow-up of 14.8 (interquartile range 14.3-15.2) years, 150 (15.6%) subjects had died. Food groups that remained independently predictive of a lower risk of death after extensive adjustment were an above-median consumption of milk (adjusted relative risk: 0.61, 95% confidence interval (CI): 0.43-0.86, P-value=0.005), fruits and vegetables (0.68, 0.46-0.98, P-value=0.041) and a moderate consumption of yogurts and cottage cheese (0.50, 95% CI: 0.31-0.81, P-value=0.005), other cheeses (0.62, 0.39-0.97, P-value=0.036) and bread (0.57, 0.37-0.89, P-value=0.014). Besides, there was a nonsignificant trend for a higher risk of death associated with highest sodium intakes.

CONCLUSIONS

Consumption of food groups that largely match recommendations is associated with a reduced risk of all-cause death in men. A diet providing moderate amounts of diverse food groups appears associated with the highest life expectancy.

Dashing away hypertension: Evaluating the efficacy of the dietary approaches to stop hypertension diet in controlling high blood pressure

The dietary approaches to stop hypertension (DASH) diet has been developed and popularized as a non-pharmaceutical intervention for high blood pressure reduction since 1995. However, to date, a comprehensive description of the biochemical rationale behind the diet’s principal guidelines has yet to be compiled. With rising interest for healthy and reliable life-style modifications to combat cardiovascular disease, this review aims to compile the most recent and relevant studies on this topic and make an informed assessment as to the efficacy of and underlying mechanisms operant in the DASH diet. Specifically, the merits of lowering dietary intake of sodium and saturated fat, as well as increasing the intake of fruits, vegetables, fiber, and dairy, have been shown to attenuate hypertension individually. Upon review of this evidence, we conclude that the combination of dietary patterns proposed in the DASH diet is effective in attenuating high blood pressure. We also suggest that efforts to more widely implement adoption of the DASH diet would be beneficial to public health.

Digital Interventions to Promote Self-Management in Adults With Hypertension: Protocol for Systematic Review and Meta-Analysis

Background

Digital interventions, defined as any intervention accessed and taking input from patients in the form of a computer/Web-based program or mobile phoned-based app, can potentially help empower patients to self-manage long-term conditions such as hypertension. Importantly, digital interventions have the potential to provide patients with personalized information and support for active involvement in treatment as well as cost saving.

Objective

The purpose of this systematic review is to synthesize the evidence for using digital interventions to support patient self-management of hypertension, and determine their impact on control and reduction of blood pressure, other clinical outcomes, quality of life, medication adherence, health service utilization, and economic benefits.

Methods

A systematic search of bibliographic databases including Medline, Embase, CINAHL, and PsycINFO will be undertaken. Abstracts and citations will be independently screened by 2 researchers against predetermined inclusion criteria. Any disagreements will be resolved by discussion and further consideration of the inclusion criteria. Only randomized controlled trials which have been published in peer peer-reviewed journals with a diagnosis of hypertension will be considered. Inclusion criteria will be (1) adults (age ≥ 18 years) with hypertension (as defined by the primary authors); (2) an interactive digital intervention compared with usual care; and (3) outcomes of objectively measured change in blood pressure. Data extraction from identified articles will be undertaken by 2 independent reviewers using a uniform template. The main outcomes are systolic blood pressure (SBP) and diastolic blood pressure (DBP), and quality of life indicators. Secondary outcomes include cost- effectiveness, medication adherence, emotional well-being, and physical activity. Risk of bias of included studies will be assessed using the Cochrane tool.

Results

Our research is currently ongoing. Data will be summarized narratively, and if possible, meta-analyses will be performed to assess the impact of the interventions on outcomes.

Conclusions

By summarizing and synthesizing available data, this review will help inform policy on the use of digital interventions for self-management of hypertension and will clarify areas for further research.

Trial Registration

Prospero 2014: CRD42014010268; http://www.crd.york.ac.uk/PROSPERO/display_record.asp? ID=CRD42014010268 (Archived by WebCite at http://www.webcitation.org/6c5alQQJL)

Fruit and vegetable consumption and cardiovascular risk factors in older Chinese: the Guangzhou biobank cohort study

OBJECTIVE

To examine the adjusted associations of fruit consumption and vegetable consumption with the Framingham score and its components in the non-Western setting of Southern China, considering health status.

METHOD

Linear regression was used to assess the cross-sectional associations of fruit and vegetable consumption with the Framingham score and its components, among 19,518 older Chinese (≥50 years) from the Guangzhou Biobank Cohort Study in Southern China (2003-2006), and whether these differed by health status.

RESULTS

The association of fruit consumption with the Framingham score varied by health status (P-value<0.001), but not vegetable consumption (P-value 0.51). Fruit consumption was associated with a lower Framingham score (-0.04 per portions/day, 95% confidence interval (CI) -0.08 to -0.004) among participants in poor health, adjusted for age, sex, recruitment phase, socio-economic position and lifestyle. However, similarly adjusted, fruit consumption was associated with a higher Framingham score (0.05, 95% CI 0.02 to 0.09) among participants in good health, perhaps due to a positive association of fruit consumption with fasting glucose. Similarly adjusted, vegetable consumption was associated with a higher Framingham score (0.03, 95% CI 0.01 to 0.05) among all participants, with no difference by health status.

CONCLUSION

This large study from a non-western setting found that fruit and vegetable consumption was barely associated with the Framingham score, or major CVD risk factors.

Sympathetic activation in resistant hypertension: theory and therapy

Resistant hypertension defined as requiring 3 or more complementary antihypertensive drugs at maximally tolerated doses accounts for approximately 3% to 4% of all cases of hypertension. Its increased incidence over the past decade is related to the increase in obesity in the Western world. There are a number of dietary factors that affect sympathetic tone including sodium intake apart from increased body mass. This article discusses the mechanisms of sympathetic stimulation and activation in the context of animal models and human studies. In addition, there is a review of clinical trials with and without device therapy that summarizes the clinical findings. Effective management should be based on pathophysiologic principles and a focus on blood pressure reduction to levels well below 150/90 mm Hg because outcome trial evidence and Food and Drug Administration guidance supports this construct. The key to success of device-based therapy depends on identifying the cohort with true resistant hypertension that can benefit from therapies that are adjuncts to pharmacotherapy. Physicians need to concentrate on educating the patient on lifestyle modifications and themselves on use of proper combinations of antihypertensive medications. If this approach fails to result in a safe level of blood pressure then the patient should be referred to a board-certified clinical hypertension specialist.

2013 Korean Society of Hypertension guidelines for the management of hypertension. Part II-treatments of hypertension

Treatment strategies are provided in accordance with the level of global cardiovascular risk, from lifestyle modification in the lower risk group to more comprehensive treatment in the higher risk group. Considering the common trend of combination drug regimen, the choice of the first drug is suggested more liberally according to the physician's discretion.

Effects of non-fat dairy products added to the routine diet on vascular function: a randomized controlled crossover trial

BACKGROUND AND AIMS

High consumption of low- and non-fat dairy products is associated with reduced risk of high blood pressure (BP) and central arterial stiffness. However, interventional studies to determine if the addition of non-fat dairy products to the diet is capable of reducing central BP and improving vascular function are lacking. The aim of this study was to determine if the solitary addition of non-fat dairy products to the normal routine diet would reduce central BP and improve vascular function in middle-aged and older adults with elevated BP.

METHODS AND RESULTS

Using a randomized, crossover intervention study design, forty-nine adults (44% men, 53 ± 2 years, 170 ± 2 cm, 88 ± 3 kg; mean ± SEM) with elevated BP (134 ± 1/81 ± 1 mm Hg) underwent a High Dairy condition (+4 servings/day of conventional non-fat dairy products) and No Dairy condition (+4 servings/day fruit products) in which all dairy products were removed. Both dietary conditions lasted 4 weeks with a 2-week washout before crossing over into the alternate condition. The High Dairy condition produced reductions in central systolic BP (-3 ± 1 mm Hg) and carotid-femoral pulse wave velocity (-0.5 ± 0.1 m/sec), with a concomitant increase in brachial flow-mediated dilation (+1.1 ± 0.4%) and cardiovagal baroreflex sensitivity (+5 ± 1 ms/mm Hg) (P < 0.05 for all vs. baseline). In the No Dairy condition, brachial flow-mediated dilation was reduced (-1.0 ± 0.1%, P < 0.05 vs. baseline).

CONCLUSIONS

The solitary manipulation of conventional dairy products in the normal routine diet modulates levels of central BP and vascular function in middle-aged and older adults with elevated BP.

CLINICAL TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT01577030.

Prevalence of taking actions to control blood pressure among adults with self-reported hypertension in 18 states and the District of Columbia, 2009

The authors used 2009 Behavioral Risk Factor Surveillance System data to assess the prevalence of taking actions to control hypertension among adults with self-reported hypertension. Differences by descriptive characteristics (sex, age, race/ethnicity, access to health care, medication adherence), presence of other health risk factors (overweight/obesity, smoking, heavy drinking, inadequate fruit/vegetable intake, and physical inactivity), and comorbidities (diabetes, high cholesterol, coronary heart disease, and stroke) were compared. The prevalence of hypertension was 29.6%, and 75.0% of these patients reported taking antihypertensive medications, 73.1% changed eating habits, 72.8% decreased the use of salt, 78.8% reduced alcohol consumption, and 69.9% increased their physical activity. Overall, 87.2% reported taking two or more actions to reduce blood pressure. Patients taking antihypertensive medications were more likely to take two or more actions than their counterparts (90.6% vs 79.4%, P<.01). Those with at least one other health risk factor were 1.85 times as likely to take two or more actions as their counterparts (95% confidence interval, 1.18-2.92 times). More than 80% of hypertensive adults reported taking two or more actions to control blood pressure. The prevalence of taking actions differed significantly by descriptive characteristics, the presence health risk factors, and comorbidities.

Dietary habits, poverty, and chronic kidney disease in an urban population

BACKGROUND

Poverty is associated with chronic kidney disease (CKD) in the United States and worldwide. Poor dietary habits may contribute to this disparity.

STUDY DESIGN

Cross-sectional study.

SETTING AND PARTICIPANTS

A total of 2,058 community-dwelling adults aged 30 to 64 years residing in Baltimore City, Maryland.

PREDICTORS

Adherence to the Dietary Approaches to Stop Hypertension (DASH) diet. DASH scoring based on 9 target nutrients (total fat, saturated fat, protein, fiber, cholesterol, calcium, magnesium, sodium, and potassium); adherence defined as score ≥4.5 of maximum possible score of 9. Poverty (self-reported household income <125% of 2004 Department of Health and Human Services guideline) and nonpoverty (≥125% of guideline).

OUTCOMES AND MEASUREMENTS

CKD defined as estimated glomerular filtration rate <60 mL/minute/1.73 m(2) (CKD epidemiology collaboration equation). Multivariable logistic regression was used to calculate adjusted odds ratios (AORs) for relation of DASH score tertile and CKD, stratified by poverty status.

RESULTS

Among 2,058 participants (mean age 48 years; 57% black; 44% male; 42% with poverty), median DASH score was low, 1.5 (interquartile range, 1-2.5). Only 5.4% were adherent. Poverty, male sex, black race, and smoking were more prevalent among the lower DASH score tertiles, whereas higher education and regular health care were more prevalent among the highest DASH score tertile (P < .05 for all). Fiber, calcium, magnesium, and potassium intake were lower, and cholesterol higher, among the poverty compared with nonpoverty group (P < .05 for all), with no difference in sodium intake. A total of 5.6% of the poverty and 3.8% of the nonpoverty group had CKD (P = .05). The lowest DASH tertile (compared with the highest) was associated with more CKD among the poverty (AOR 3.15, 95% confidence interval 1.51-6.56), but not among the nonpoverty group (AOR 0.73, 95% confidence interval 0.37-1.43; P interaction = .001).

CONCLUSIONS

Poor dietary habits are strongly associated with CKD among the urban poor and may represent a target for interventions aimed at reducing disparities in CKD.

Altered dietary salt intake for people with chronic kidney disease

BACKGROUND

Salt intake shows great promise as a modifiable risk factor for reducing heart disease incidence and delaying kidney function decline in people with chronic kidney disease (CKD). However, a clear consensus of the benefits of reducing salt in people with CKD is lacking.

OBJECTIVES

This review evaluated the benefits and harms of altering dietary salt intake in people with CKD.

SEARCH METHODS

We searched the Cochrane Renal Group's Specialised Register to 13 January 2015 through contact with the Trials' Search Co-ordinator using search terms relevant to this review.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) that compared two or more levels of salt intake in people with any stage of CKD.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed studies for eligibility and conducted risk of bias evaluation. Results were expressed as risk ratios (RR) and their 95% confidence intervals (CI) for dichotomous outcomes, and mean difference (MD) and 95% CI for continuous outcomes. Mean effect sizes were calculated using the random-effects models.

MAIN RESULTS

We included eight studies (24 reports, 258 participants). Because duration of the included studies was too short (1 to 26 weeks) to test the effect of salt restriction on endpoints such as mortality, cardiovascular events or CKD progression, changes in salt intake on blood pressure and other secondary risk factors were applied. Three studies were parallel RCTs and five were cross-over studies. Selection bias was low in five studies and unclear in three. Performance and detection biases were low in two studies and unclear in six. Attrition and reporting biases were low in four studies and unclear in four. One study had the potential for high carryover effect; three had high risk of bias from baseline characteristics (change of medication or diet) and two studies were industry funded.There was a significant reduction in 24 hour sodium excretion associated with low salt interventions (range 52 to 141 mmol) (8 studies, 258 participants: MD -105.86 mmol/d, 95% CI -119.20 to -92.51; I(2) = 51%). Reducing salt intake significantly reduced systolic blood pressure (8 studies, 258 participants: MD -8.75 mm Hg, 95% CI -11.33 to -6.16; I(2) = 0%) and diastolic blood pressure (8 studies, 258 participants: MD -3.70 mm Hg, 95% CI -5.09 to -2.30; I(2) = 0%). One study reported restricting salt intake reduced the risk of oedema by 56%. Salt restriction significantly increased plasma renin activity (2 studies, 71 participants: MD 1.08 ng/mL/h, 95% CI 0.51 to 1.65; I(2) = 0%) and serum aldosterone (2 studies, 71 participants: 6.20 ng/dL (95% CI 3.82 to 8.58; I(2) = 0%). Antihypertensive medication dosage was significantly reduced with a low salt diet (2 studies, 52 participants): RR 5.48, 95% CI 1.27 to 23.66; I(2) = 0%). There was no significant difference in eGFR (2 studies, 68 participants: MD -1.14 mL/min/1.73 m(2), 95% CI -4.38 to 2.11; I(2) = 0%), creatinine clearance (3 studies, 85 participants): MD -4.60 mL/min, 95% CI -11.78 to 2.57; I(2) = 0%), serum creatinine (5 studies, 151 participants: MD 5.14 µmol/L, 95% CI -8.98 to 19.26; I(2) = 59%) or body weight (5 studies, 139 participants: MD -1.46 kg; 95% CI -4.55 to 1.64; I(2) = 0%). There was no significant change in total cholesterol in relation to salt restriction (3 studies, 105 participants: MD -0.23 mmol/L, 95% CI -0.57 to 0.10; I(2) = 0%) or symptomatic hypotension (2 studies, 72 participants: RR 6.60, 95% CI 0.77 to 56.55; I(2) = 0%). Salt restriction significantly reduced urinary protein excretion in all studies that reported proteinuria as an outcome, however data could not be meta-analysed.

AUTHORS' CONCLUSIONS

We found a critical evidence gap in long-term effects of salt restriction in people with CKD that meant we were unable to determine the direct effects of sodium restriction on primary endpoints such as mortality and progression to end-stage kidney disease (ESKD). We found that salt reduction in people with CKD reduced blood pressure considerably and consistently reduced proteinuria. If such reductions could be maintained long-term, this effect may translate to clinically significant reductions in ESKD incidence and cardiovascular events. Research into the long-term effects of sodium-restricted diet for people with CKD is warranted, as is investigation into adherence to a low salt diet.

Effectiveness of 6 months of tailored text message reminders for obese male participants in a worksite weight loss program: randomized controlled trial

Background

Worksite nutrition and physical activity interventions are important to help overweight and obese employees lose weight, but costs and insufficient sustained motivation prevent the majority of these programs from succeeding. Tailored text messaging in aiding weight management has been effective in several studies, but no studies have evaluated the effect of a tailored text message service on weight loss in a worksite health promotion program.

Objective

We studied the efficacy of a tailored text-messaging intervention for obese male participants in a worksite weight loss program of 6 months duration.

Methods

The study was an unblinded, randomized controlled trial. Men with a body mass index greater than 25 kg/m² were recruited from the Korea District Heating Corporation, the Korea Expressway Corporation, and the Korea Gas Corporation. The participants were identified by nurse managers. Participants were randomly allocated to 1 of the following 2 groups for 24 weeks: (1) intervention group, which received tailored text message reminders every other day plus 4 offline education sessions and brief counseling with monthly weight check by nurses for weight control over 6 months and (2) control group, which received the 4 offline education sessions and brief counseling with monthly weight check by nurses about weight control over 6 months. The primary outcome was the difference in weight loss at 6 months. A mixed-model repeated-measures analysis was performed to evaluate the effect of the intervention group’s weight loss compared with the control group.

Results

A total of 205 obese men were randomized into either the intervention (n=104) or the control group (n=101). At the end of 6 months, the intervention group (n=63) had lost 1.71 kg (95% CI –2.53 to –0.88) and the control group (n=59) had lost 1.56 kg (95% CI –2.45 to –0.66); the difference between the 2 groups was not significant (mean difference –0.15, 95% CI –1.36 to 1.07). At the end of the study, 60% (34/57) of the intervention group rated the message program as helpful for weight control and 46% (26/57) would recommend the text message service to their friends.

Conclusions

Tailored text message reminders did not have a significant effect on weight loss in obese men as part of a worksite weight loss program.

Trial Registration

International Standard Randomized Controlled Trial Number (ISRCTN): 39629189; http://www.isrctn.com/ISRCTN39629189?q=39629189&filters=&sort=&offset=1&totalResults=1&page=1&pageSize=10&searchType=basic-search (Archived by WebCite at http://www.webcitation.org/6VsFkwJH6).

Dietary factors and higher blood pressure in African-Americans

Adverse blood pressure (BP) is a major independent risk factor for epidemic cardiovascular diseases affecting almost one third of the US adult population. This review synthesizes results from studies published over the past few years on BP differences and prevalent hypertension between US blacks and whites and their different intakes of foods (e.g., fruits, vegetables, and dairy products) and micronutrients (e.g., vitamin D, calcium, potassium, and phosphorus). Studies have consistently reported higher prevalence of adverse BP levels and hypertension and less favorable dietary intakes in blacks than in whites, but the influence of specific dietary factors on high BP risk for blacks remains unclear.

Metabolic syndrome from adolescence to early adulthood: effect of infancy-onset dietary counseling of low saturated fat: the Special Turku Coronary Risk Factor Intervention Project (STRIP)

BACKGROUND

Adolescent metabolic syndrome (MetS) predicts type 2 diabetes mellitus and subclinical atherosclerosis in adulthood. Our aim was to establish the relationship between an infancy-onset dietary intervention and risk of having MetS between 15 and 20 years of age.

METHODS AND RESULTS

The Special Turku Coronary Risk Factor Intervention Project for Children (STRIP) study is a longitudinal, randomized atherosclerosis prevention trial in which repeated dietary counseling aiming at reducing intake of saturated fat took place from infancy to early adulthood. Participants who had complete data on the MetS components (waist circumference, blood pressure, triglycerides, glucose, high-density lipoprotein cholesterol) at 15 (n=512), 16 (n=485), 17 (n=475), 18 (n=459), 19 (n=439), and 20 (n=407) years of age were included in the study. Modified International Diabetes Foundation criteria with 80th/20th percentile cutoff points for the components were primarily applied in statistical analyses, and the results were replicated with the use of other pediatric MetS definitions. Between the ages of 15 and 20 years, the prevalence of MetS varied between 6.0% and 7.5% in participants in the intervention group and between 10% and 14% in the control group. The long-term relative risk of MetS was significantly lower in the intervention group (relative risk, 0.59; 95% confidence interval, 0.40-0.88; P=0.009). Of the individual MetS components, the intervention decreased risk of high blood pressure in both sexes (relative risk, 0.83; 95% confidence interval, 0.70-0.99) and high triglycerides in male subjects (relative risk, 0.71; 95% confidence interval, 0.52-0.98). A statistically nonsignificant reduction was seen in the risk of high waist circumference in the intervention individuals (relative risk, 0.78; 95% confidence interval, 0.59-1.03).

CONCLUSION

Repeated infancy-onset dietary intervention is effective in the prevention of MetS in adolescence.

CLINICAL TRIAL REGISTRATION URL

http://www.clinicaltrials.gov. Unique identifier: NCT00223600.

Perceived barriers and facilitators of using dietary modification for CKD prevention among African Americans of low socioeconomic status: a qualitative study

Background

Factors influencing the use of dietary interventions for modification of CKD risk among African Americans have not been well-explored. We assessed perceived barriers and facilitators of CKD prevention through dietary modifications among African Americans with low socioeconomic status (SES) and at high risk for CKD.

Methods

We conducted a qualitative study involving three 90 minute focus groups of low SES (limited education, unemployed, uninsured, or income < $25,000/year) African American residents of Baltimore, Maryland (N = 17), who were aged 18-60 years, with no known history of CKD and (1) a family history of end stage renal disease and (2) self-reported diabetes, hypertension, cardiovascular disease, HIV or obesity. A trained moderator asked a series of 21 closed and open-ended questions. Group sessions were recorded, transcribed, and two independent investigators reviewed transcripts to identify common themes.

Results

Participants’ mean (SD) age was 39.8 (12.4) years. Most (59%) were female and earned < $5,000/year (71%). One quarter (24%) had self-reported diabetes and over half had hypertension (53%). Few (12%) perceived their CKD risk as high. Perceived barriers to CKD prevention through dietary change included the expense and unavailability of healthy foods, family member preferences, convenience of unhealthy foods, and inability to break lifelong habits. They identified vouchers for healthy foods, family-based interventions, nutritional counseling and group gatherings for persons interested in making dietary changes as acceptable facilitators of dietary CKD prevention efforts.

Conclusions

Low SES African Americans at high risk for CKD had limited perception of their risk but they identified multiple barriers and potential facilitators of CKD prevention via dietary modifications which can inform future studies and public health interventions.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2369-15-194) contains supplementary material, which is available to authorized users.

Managing the side effects associated with commonly used treatments for bipolar depression

BACKGROUND

The most commonly used pharmacologic therapies for bipolar depression are mood stabilizers, atypical antipsychotics, and antidepressants. This paper reviews common side effects associated with these medications and provides recommendations for managing adverse medication effects in clinical practice.

METHODS

Narrative review based on literature searches of Medline and evidence-based treatment guidelines for agents that have been approved by the US Food and Drug Administration and/or are commonly used to treat bipolar depression.

RESULTS

Side effects of bipolar depression pharmacotherapies are common and vary by medication, with weight gain, metabolic dysregulation, sedation/somnolence, and akathisia among those observed most frequently. These adverse events (weight gain and sedation/somnolence, in particular) negatively affect treatment adherence in patients with bipolar disorder. Furthermore, endocrine and metabolic comorbidities, weight gain, and obesity may reduce the likelihood of positive clinical responses to pharmacologic therapies. Clinicians may consider switching patients to bipolar depression medication(s) with a lower propensity for sedation or adverse metabolic effects. Lifestyle modification (e.g., dietary changes, exercise) is an important component in the treatment of weight gain/obesity, dyslipidemia, hypertension, and hyperglycemia; in addition, a wide range of medications are available as therapeutic options for patients in whom non-pharmacologic management strategies are insufficient. The use of adjunctive medication may also reduce treatment-related sedation and somnolence.

LIMITATIONS

The selection of relevant studies from the literature search relied primarily on the author's expertise in the area of bipolar depression and knowledge of the issues addressed.

CONCLUSION

Successful treatment of bipolar depression extends beyond managing mood symptoms to also monitoring adverse medication events and managing associated medical disorders.

To legislate or not to legislate? A comparison of the UK and South African approaches to the development and implementation of salt reduction programs

The World Health Organization promotes salt reduction as a best-buy strategy to reduce chronic diseases, and Member States have agreed to a 30% reduction target in mean population salt intake by 2025. Whilst the UK has made the most progress on salt reduction, South Africa was the first country to pass legislation for salt levels in a range of processed foods. This paper compares the process of developing salt reduction strategies in both countries and highlights lessons for other countries. Like the UK, the benefits of salt reduction were being debated in South Africa long before it became a policy priority. Whilst salt reduction was gaining a higher profile internationally, undoubtedly, local research to produce context-specific, domestic costs and outcome indicators for South Africa was crucial in influencing the decision to legislate. In the UK, strong government leadership and extensive advocacy activities initiated in the early 2000s have helped drive the voluntary uptake of salt targets by the food industry. It is too early to say which strategy will be most effective regarding reductions in population-level blood pressure. Robust monitoring and transparent mechanisms for holding the industry accountable will be key to continued progress in each of the countries.

Dietary approaches to prevent hypertension

Elevated blood pressure arises from a combination of environmental and genetic factors and the interactions of these factors. A substantial body of evidence from animal studies, epidemiologic studies, meta-analyses, and randomized controlled trials has demonstrated that certain dietary patterns and individual dietary elements play a prominent role in the development of hypertension. Changes in diet can lower blood pressure, prevent the development of hypertension, and reduce the risk of hypertension-related complications. Dietary strategies for the prevention of hypertension include reducing sodium intake, limiting alcohol consumption, increasing potassium intake, and adopting an overall dietary pattern such as the DASH (Dietary Approaches to Stop Hypertension) diet or a Mediterranean diet. In order to reduce the burden of blood pressure-related complications, efforts that focus on environmental and individual behavioral changes that encourage and promote healthier food choices are warranted.

Racial differences in hypertension: implications for high blood pressure management

The racial disparity in hypertension and hypertension-related outcomes has been recognized for decades with African Americans with greater risks than Caucasians. Blood pressure levels have consistently been higher for African Americans with an earlier onset of hypertension. Although awareness and treatment levels of high blood pressure have been similar, racial differences in control rates are evident. The higher blood pressure levels for African Americans are associated with higher rates of stroke, end-stage renal disease and congestive heart failure. The reasons for the racial disparities in elevated blood pressure and hypertension-related outcomes risk remain unclear. However, the implications of the disparities of hypertension for prevention and clinical management are substantial, identifying African American men and women with excel hypertension risk and warranting interventions focused on these differences. In addition, focused research to identify the factors attributed to these disparities in risk burden is an essential need to address the evidence gaps.

Effect of a low-fat or low-carbohydrate weight-loss diet on markers of cardiovascular risk among premenopausal women: a randomized trial

BACKGROUND

Low-fat and low-carbohydrate weight-loss diets can have a beneficial effect on longitudinal measures of blood pressure and blood lipids. We aimed to assess longitudinal changes in blood pressure and blood lipids in a population of premenopausal women. We hypothesized that results may differ by level of adherence to the respective diet protocol and baseline presence of hypertension or hyperlipidemia.

METHODS

Overweight or obese premenopausal women were randomized to a low-fat (n=41) or low-carbohydrate (n=38) diet. As part of the 52-week Lifestyle Eating and Fitness (LEAF) intervention trial, we fit linear mixed models to determine whether a change in outcome differed by treatment arm.

RESULTS

Within-group trends in blood pressure and blood lipids did not differ (p>0.30). Across study arms, there was a significant decrease in systolic blood pressure (SBP, 3 mm Hg, p=0.01) over time, but diastolic blood pressure (DBP) did not change significantly over the course of the study. Blood lipids (total cholesterol [TC], low-density lipoproteins [LDL], and high-density lipoproteins [HDL]) all exhibited nonlinear trends over time (p<0.01); each decreased initially but returned to levels comparable to baseline by study conclusion (p>0.20). We observed a decline in SBP among women who were hypertensive at baseline (p<0.01), but hypercholesterolemia at baseline did not affect trends in blood lipids (p>0.40).

CONCLUSIONS

Our results support that dietary interventions may be efficacious for lowering blood pressure and blood lipids among overweight or obese premenopausal women. However, a decrease in SBP was the only favorable change that was sustained in this study population. These changes can be maintained over the course of a 1-year intervention, yet changes in blood lipids may be less sustainable.

Hypotensive effects of solitary addition of conventional nonfat dairy products to the routine diet: a randomized controlled trial

BACKGROUND

The high consumption of low-fat and nonfat dairy products is associated with reduced risk of high blood pressure.

OBJECTIVE

We aimed to investigate whether the solitary addition of nonfat dairy products to the normal routine diet was capable of lowering blood pressure in middle-aged and older adults with elevated blood pressure.

DESIGN

With the use of a randomized, crossover intervention-study design, 49 adults (56% women) with elevated blood pressure (mean ± SEM age: 53 ± 2 y; systolic blood pressure: 135 ± 1; diastolic blood pressure: 80 ± 1 mm Hg) underwent a high-dairy condition (+4 servings conventional nonfat dairy products/d) and isocaloric no-dairy condition (+4 servings fruit products/d) in which all dairy products were removed. Both dietary conditions lasted 4 wk with a 2-wk washout before crossing over into the alternate condition.

RESULTS

The high-dairy condition produced reductions in systolic blood pressure (135 ± 1 to 127 ± 1 mm Hg) and pulse pressure (54 ± 1 to 48 ± 1 mm Hg) (both P < 0.05). The hypotensive effects were observed within 3 wk after the initiation of the dietary intervention and in both casual seated and ambulatory (24-h) measurements (P < 0.05). Pulse pressure was increased after the removal of all dairy products in the no-dairy condition (54 ± 1 to 56 ± 1 mm Hg; P < 0.05). There were no changes in diastolic blood pressure after either dietary condition.

CONCLUSION

We concluded that the solitary manipulation of conventional dairy products in the normal routine diet would modulate blood pressure in middle-aged and older adults with prehypertension and hypertension. This trial was registered at clinicaltrials.gov as NCT01577030.

Socioeconomic factors and racial disparities in kidney disease outcomes

African Americans suffer disproportionately from advanced and progressive chronic kidney disease (CKD). Socioeconomic factors are believed to play an important role in this disparity, and likely influence African Americans' increased risk of CKD through multiple pathways. Low socioeconomic status (SES) may contribute to racial disparities in CKD because of the greater prevalence of poverty, for example, among African Americans as compared with whites. However, low SES has a stronger relation with CKD among African Americans than among whites, underscoring that the context and magnitude of socioeconomic influences on CKD outcomes varies between these populations. These socioeconomic influences may produce new or potentiate existing racial differences in biology. This review discusses what is known about the role of SES in explaining racial disparities in CKD, highlights several knowledge gaps in this area, and suggests future directions toward the elimination of disparities in CKD.

e-Care for heart wellness: a feasibility trial to decrease blood pressure and cardiovascular risk

BACKGROUND

Pharmacist- or nurse-led team care decreases patient blood pressure (BP) and cardiovascular disease (CVD) risk.

PURPOSE

To evaluate whether a Web-based dietitian-led (WD) team care intervention was feasible and resulted in decreased BP, CVD risk, and weight compared to usual care (UC).

METHODS

Electronic health record (EHR) data identified patients aged 30-69 years with BMI >26, elevated BP, and 10%-25% 10-year Framingham CVD risk who were registered patient website users. Patients with uncontrolled BP at screening were randomized to UC or WD, which included a home BP monitor, scale, and dietitian team care. WD participants had a single in-person dietitian visit to obtain baseline information and create a plan to reduce CVD risk. Planned follow-up occurred via secure messaging to report BP, weight, and fruit and vegetable intake and receive ongoing feedback. If needed, dietitians encouraged patients and their physicians to intensify antihypertensive and lipid-lowering medications. Primary outcomes were change in systolic BP and weight loss ≥4 kg at 6 months. Feasibility outcomes included intervention utilization and satisfaction.

RESULTS

Between 2010 and 2011, a total of 90 of 101 participants completed 6-month follow-ups. The WD group had higher rates of secure messaging utilization and patient satisfaction. The WD group lost significantly more weight than the UC group (adjusted net difference=-3.2 kg, 95% CI=-5.0, -1.5, p<0.001) and was more likely to lose ≥4 kg (adjusted relative risk [RRadj]=2.96, 95% CI=1.16, 7.53). BP control and CVD risk reduction were greater in WD than UC, but differences were not statistically significant.

CONCLUSIONS

WD intervention was feasible and resulted in decreased weight, BP, and CVD risk. A larger trial is justified.

TRIAL REGISTRATION NUMBER

Trial Registration Number: NCT01077388.

TEMPOL enhances the antihypertensive effects of sodium nitrite by mechanisms facilitating nitrite-derived gastric nitric oxide formation

Orally administered nitrite exerts antihypertensive effects associated with increased gastric nitric oxide (NO) formation. While reducing agents facilitate NO formation from nitrite, no previous study has examined whether antioxidants with reducing properties improve the antihypertensive responses to orally administered nitrite. We hypothesized that TEMPOL (4-hydroxy-2,2,6,6-tetramethylpiperidine-N-oxyl) could enhance the hypotensive effects of nitrite in hypertensive rats by exerting antioxidant effects (and enhancing NO bioavailability) and by promoting gastric nitrite-derived NO generation. The hypotensive effects of intravenous and oral sodium nitrite were assessed in unanesthetized freely moving rats with L-NAME (N(ω)-nitro-L-arginine methyl ester; 100mg/kg; po)-induced hypertension treated with TEMPOL (18mg/kg; po) or vehicle. While TEMPOL exerted antioxidant effects in hypertensive rats, as revealed by lower plasma 8-isoprostane and vascular reactive oxygen species levels, this antioxidant did not affect the hypotensive responses to intravenous nitrite. Conversely, TEMPOL enhanced the dose-dependent hypotensive responses to orally administered nitrite, and this effect was associated with higher increases in plasma nitrite and lower increases in plasma nitrate concentrations. In vitro experiments using electrochemical and chemiluminescence NO detection under variable pH conditions showed that TEMPOL enhanced nitrite-derived NO formation, especially at low pH (2.0 to 4.0). TEMPOL signal evaluated by electron paramagnetic resonance decreased when nitrite was reduced to NO under acidic conditions. Consistent with these findings, increasing gastric pH with omeprazole (30mg/kg; po) attenuated the hypotensive responses to nitrite and blunted the enhancement in plasma nitrite concentrations and hypotensive effects induced by TEMPOL. Nitrite-derived NO formation in vivo was confirmed by using the NO scavenger 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (C-PTIO), which blunted the responses to oral nitrite. Our results showed that TEMPOL promotes nitrite reduction to NO in the stomach and enhanced plasma nitrite concentrations and the hypotensive effects of oral sodium nitrite through mechanisms critically dependent on gastric pH. Interestingly, the effects of TEMPOL on nitrite-mediated hypotension cannot be explained by increased NO formation in the stomach alone, but rather appear more directly related to increased plasma nitrite levels and reduced nitrate levels during TEMPOL treatment. This may relate to enhanced nitrite uptake or reduced nitrate formation from NO or nitrite.

Association between usual sodium and potassium intake and blood pressure and hypertension among U.S. adults: NHANES 2005-2010

OBJECTIVES

Studies indicate high sodium and low potassium intake can increase blood pressure suggesting the ratio of sodium-to-potassium may be informative. Yet, limited studies examine the association of the sodium-to-potassium ratio with blood pressure and hypertension.

METHODS

We analyzed data on 10,563 participants aged ≥20 years in the 2005-2010 National Health and Nutrition Examination Survey who were neither taking anti-hypertensive medication nor on a low sodium diet. We used measurement error models to estimate usual intakes, multivariable linear regression to assess their associations with blood pressure, and logistic regression to assess their associations with hypertension.

RESULTS

The average usual intakes of sodium, potassium and sodium-to-potassium ratio were 3,569 mg/d, 2,745 mg/d, and 1.41, respectively. All three measures were significantly associated with systolic blood pressure, with an increase of 1.04 mmHg (95% CI, 0.27-1.82) and a decrease of 1.24 mmHg (95% CI, 0.31-2.70) per 1,000 mg/d increase in sodium or potassium intake, respectively, and an increase of 1.05 mmHg (95% CI, 0.12-1.98) per 0.5 unit increase in sodium-to-potassium ratio. The adjusted odds ratios for hypertension were 1.40 (95% CI, 1.07-1.83), 0.72 (95% CI, 0.53-0.97) and 1.30 (95% CI, 1.05-1.61), respectively, comparing the highest and lowest quartiles of usual intake of sodium, potassium or sodium-to-potassium ratio.

CONCLUSIONS

Our results provide population-based evidence that concurrent higher sodium and lower potassium consumption are associated with hypertension.

Evaluation of a self-management implementation intervention to improve hypertension control among patients in Medicaid

Elevated blood pressure can lead to serious patient morbidity and mortality. The aim of the study was to evaluate the implementation of a tailored multifaceted program, administered by care managers in a Medicaid setting to improve hypertension medication adherence. The program enrolled 558 Medicaid patients. Patients had at least one phone call by care managers. The individually tailored program focused on improving lifestyle and medication adherence. The primary outcome was the medication possession ratio (MPR), calculated using fill history from pharmacy claims. We observed an improvement of medication possession from 55% 9-12 months prior to program enrollment to 77% 9-12 months post initiation of the program. We demonstrated 12 month sustainability and increased MPR. Personal interaction by phone allows the intervention to be tailored to participants' current concerns, health goals, and specific barriers to achieving these goals.

Lycopene supplement and blood pressure: an updated meta-analysis of intervention trials

Epidemiological studies suggested that lycopene supplement could decrease blood pressure, but the results were conflicting. We conducted an updated meta-analysis by screening PubMed databases, and calculated the combined effect size using a random effect model. In addition, subgroup analysis stratified by baseline blood pressure, lycopene dosage, duration, study location and the funding support of the paper was also conducted. Six studies met our inclusion criteria, and the pooled analysis demonstrated a significant reduction of systolic blood pressure (SBP) (mean SBP = −4.953 [−8.820, −1.086], p = 0.012) with obvious heterogeneity (p = 0.034, I² = 58.5%). Subgroup analysis results showed that higher dosage of lycopene supplement (>12 mg/day) could lower SBP more significantly, especially for participants with baseline SBP >120 mmHg, or Asians, while lycopene intervention had no statistical effect on diastolic blood pressure (DBP) (mean DBP = −3.809 [−8.177, 0.560], p = 0.087), and obvious heterogeneity was also observed (p = 0.074, I² = 53.1%). Our present study suggests that lycopene supplement >12 mg/day might effectively decrease SBP, particularly among Asians or population with higher baseline SBP.

Effect of dietary nitrate on blood pressure, endothelial function, and insulin sensitivity in type 2 diabetes

Diets rich in green, leafy vegetables have been shown to lower blood pressure (BP) and reduce the risk of cardiovascular disease. Green, leafy vegetables and beetroot are particularly rich in inorganic nitrate. Dietary nitrate supplementation, via sequential reduction to nitrite and NO, has previously been shown to lower BP and improve endothelial function in healthy humans. We sought to determine if supplementing dietary nitrate with beetroot juice, a rich source of nitrate, will lower BP and improve endothelial function and insulin sensitivity in individuals with type 2 diabetes (T2DM). Twenty-seven patients, age 67.2±4.9 years (18 male), were recruited for a double-blind, randomized, placebo-controlled crossover trial. Participants were randomized to begin, in either order, a 2-week period of supplementation with 250ml beetroot juice daily (active) or 250ml nitrate-depleted beetroot juice (placebo). At the conclusion of each intervention period 24-h ambulatory blood pressure monitoring, tests of macro- and microvascular endothelial function, and a hyperinsulinemic isoglycemic clamp were performed. After 2 weeks administration of beetroot juice mean ambulatory systolic BP was unchanged: 134.6±8.4mmHg versus 135.1±7.8mmHg (mean±SD), placebo vs active-mean difference of -0.5mmHg (placebo-active), p=0.737 (95% CI -3.9 to 2.8). There were no changes in macrovascular or microvascular endothelial function or insulin sensitivity. Supplementation of the diet with 7.5mmol of nitrate per day for 2 weeks caused an increase in plasma nitrite and nitrate concentration, but did not lower BP, improve endothelial function, or improve insulin sensitivity in individuals with T2DM.

A diet pattern with more dairy and nuts, but less meat is related to lower risk of developing hypertension in middle-aged adults: the Atherosclerosis Risk in Communities (ARIC) study

Dietary intake among other lifestyle factors influence blood pressure. We examined the associations of an “a priori” diet score with incident high normal blood pressure (HNBP; systolic blood pressure (SBP) 120–139 mmHg, or diastolic blood pressure (DBP) 80–89 mmHg and no antihypertensive medications) and hypertension (SBP ≥ 140 mmHg, DBP ≥ 90 mmHg, or taking antihypertensive medication). We used proportional hazards regression to evaluate this score in quintiles (Q) and each food group making up the score relative to incident HNBP or hypertension over nine years in the Atherosclerosis Risk of Communities (ARIC) study of 9913 African-American and Caucasian adults aged 45–64 years and free of HNBP or hypertension at baseline. Incidence of HNBP varied from 42.5% in white women to 44.1% in black women; and incident hypertension from 26.1% in white women to 40.8% in black women. Adjusting for demographics and CVD risk factors, the “a priori” food score was inversely associated with incident hypertension; but not HNBP. Compared to Q1, the relative hazards of hypertension for the food score Q2–Q5 were 0.97 (0.87–1.09), 0.91 (0.81–1.02), 0.91 (0.80–1.03), and 0.86 (0.75–0.98); p_trend = 0.01. This inverse relation was largely attributable to greater intake of dairy products and nuts, and less meat. These findings support the 2010 Dietary Guidelines to consume more dairy products and nuts, but suggest a reduction in meat intake.

High sodium:potassium intake ratio increases the risk for all-cause mortality: the REasons for Geographic And Racial Differences in Stroke (REGARDS) study

Increased dietary Na intake and decreased dietary K intake are associated with higher blood pressure. It is not known whether the dietary Na:K ratio is associated with all-cause mortality or stroke incidence and whether this relationship varies according to race. Between 2003 and 2007, the REasons for Geographic And Racial Differences in Stroke (REGARDS) cohort enrolled 30 239 black and white Americans aged 45 years or older. Diet was assessed using the Block 98 FFQ and was available on 21 374 participants. The Na:K ratio was modelled in race- and sex-specific quintiles for all analyses, with the lowest quintile (Q1) as the reference group. Data on other covariates were collected using both an in-home assessment and telephone interviews. We identified 1779 deaths and 363 strokes over a mean of 4·9 years. We used Cox proportional hazards models to obtain multivariable-adjusted hazard ratios (HR). In the highest quintile (Q5), a high Na:K ratio was associated with all-cause mortality (Q5 v. Q1 for whites: HR 1·22; 95 % CI 1·00, 1·47, P for trend = 0·084; for blacks: HR 1·36; 95 % CI 1·04, 1·77, P for trend = 0·028). A high Na:K ratio was not significantly associated with stroke in whites (HR 1·29; 95 % CI 0·88, 1·90) or blacks (HR 1·39; 95 % CI 0·78, 2·48), partly because of the low number of stroke events. In the REGARDS study, a high Na:K ratio was associated with all-cause mortality and there was a suggestive association between the Na:K ratio and stroke. These data support the policies targeted at reduction of Na from the food supply and recommendations to increase K intake.

Dairy and blood pressure: a fresh look at the evidence

The Dietary Guidelines for Americans, 2010 indicated there is moderate evidence for an association between the consumption of dairy foods and lower blood pressure in adults; however, it also stated that more evidence was needed, especially in clinical trials, to fully delineate a causal relationship. The purpose of this review is to provide background by examining the historical literature and the evidence reviewed by the 2010 Dietary Guidelines Advisory Committee, to examine the gaps in knowledge indicated by that committee, and to determine if recently published evidence is sufficient to elucidate or dismiss an association between dairy foods and blood pressure maintenance. Examination of the newly published literature, together with evaluation of the evidence as a whole, shows that the preponderance of evidence indicates dairy foods are beneficially associated with blood pressure; however, additional research is necessary to identify the mechanism of action of dairy foods. New evidence should come from carefully designed clinical trials that examine not only blood pressure outcomes but also the ability of dairy foods to affect the vasculature.

A review of nutritional factors in hypertension management

Hypertension is a major health problem worldwide. Its attendant morbidity and mortality complications have a great impact on patient's quality of life and survival. Optimizing blood pressure control has been shown to improve overall health outcomes. In addition to pharmacological therapies, nonpharmacological approach such as dietary modification plays an important role in controlling blood pressure. Many dietary components such as sodium, potassium, calcium, and magnesium have been studied substantially in the past decades. While some of these nutrients have clear evidence for their recommendation, some remain controversial and are still of ongoing study. Dietary modification is often discussed with patients and can provide a great benefit in blood pressure regulation. As such, reviewing the current evidence will be very useful in guiding patients and their physician and/or dietician in decision making. In this review article of nutritional factors in hypertension management, we aim to examine the role of nutritional factors individually and as components of whole dietary patterns.

The older patient with hypertension: care and cure

Hypertension is one of the most important clinical conditions affecting older people. Its prevalence in this group of subjects is above 60% and continues to grow. Isolated systolic hypertension accounts for the majority of cases as systolic blood pressure increases with advancing age, while diastolic blood pressure remains unchanged or even decreases. Nowadays hypertension is a well established risk factor for stroke and cardiovascular disease among older people and its treatment is considered mandatory. The general recommended blood pressure goal in uncomplicated hypertension is less than 140/90 mmHg, even if this target in older people is based mainly on expert opinion. All patients should receive nonpharmacological treatment, in particular reduction in excess body weight when body mass index is greater than 26 kg/m(2) and dietary salt restriction. Older patients with hypertension may also benefit from smoking cessation, physical activity and alcohol restriction. In relation to drug therapy, a low-dose thiazide diuretic could be a good first step. Other first-line drugs are long-acting calcium channel blockers, generally dihydropyridines, and angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers. The HYVET study showed a specific protective effect of indapamide with or without perindopril in people older than 80 years. Since monotherapy normalizes blood pressure in only 40-50% of cases, a combination of two or more drugs is often required. Moreover the addiction of a second drug may reduce the dose-related adverse effects of the first one. Finally, compliance with treatment should always be achieved by giving complete information to patients and simplifying the drug regimen as much as possible.