The effects of dietary patterns on urinary albumin excretion: results of the Dietary Approaches to Stop Hypertension (DASH) Trial

Chronic Kidney Disease Diets for Kidney Failure Prevention: Insights from the IL-11 Paradigm

Nearly every fifth adult in the United States and many older adults worldwide are affected by chronic kidney disease (CKD), which can progress to kidney failure requiring invasive kidney replacement therapy. In this review, we briefly examine the pathophysiology of CKD and discuss emerging mechanisms involving the physiological resolution of kidney injury by transforming growth factor beta 1 (TGFβ1) and interleukin-11 (IL-11), as well as the pathological consequences of IL-11 overproduction, which misguides repair processes, ultimately culminating in CKD. Taking these mechanisms into account, we offer an overview of the efficacy of plant-dominant dietary patterns in preventing and managing CKD, while also addressing their limitations in terms of restoring kidney function or preventing kidney failure. In conclusion, this paper outlines novel regeneration strategies aimed at developing a reno-regenerative diet to inhibit IL-11 and promote repair mechanisms in kidneys affected by CKD.

The association of dietary approaches to stop hypertension (DASH) with the odds of diabetic nephropathy and metabolic markers in women: a case-control study

OBJECTIVES

Epidemiologic studies have reported that diet is associated with diabetes and its complications through different pathways. We sought to examine the associations between the Dietary Approaches to Stop Hypertension (DASH) diet and the odds of diabetic nephropathy (DN) developing in Iranian women with existing type 2 diabetes.

METHODS

In this case-control study, 105 women with DN and 105 controls, matched for age and diabetes duration, were selected from the Kowsar Diabetes Clinic in Semnan, Iran. DASH, estimated using dietary intake, was assessed using a validated and reliable food frequency questionnaire with 147 items. Anthropometric measurements were assessed for all subjects. Logistic regression was performed to examine the association between DASH and the odds of developing DN.

RESULTS

After controlling for potential confounders, subjects in the highest intake of DASH diet adherence have 84% lower odds of DN, compared to those with the lowest intake (OR = 0.16, 95% CI = 0.07-0.34, P < 0.001). Among DASH diet subcategories, intakes of vegetables (80%), fruits (88%), nuts and legumes (87%), and low-fat dairy (73%) decreased the risk of DN after adjustment for confounders (P < 0.001).

CONCLUSIONS

This study showed that the DASH diet is associated with lower odds of DN development in women with type 2 diabetes.

Paradigm shift in lifestyle modification for solitary kidney after donor nephrectomy

PURPOSE OF REVIEW

Living donor kidney transplantation potentially leads to long-term complications including chronic kidney disease, end-stage kidney disease, elevated blood pressure, and pregnancy-associated hypertension. Given living donors generally do not have underlying medical conditions, lifestyle modifications, particularly dietary interventions may prevent those complications and improve their health outcomes.

RECENT FINDINGS

Glomerular hyperfiltration occurs as physiologic adaptation during an initial postdonor nephrectomy period. In the long-term, these adaptations may become pathologic consequences resulting from hyperfiltration-mediated kidney injury and ultimately secondary focal segmental glomerulosclerosis in the solitary kidney. Dietary interventions to slow a decline in kidney function include low protein intake of <0.8 g/kg/day and low sodium consumption of 2-4 g/day as well as certain health dietary patterns. There is no evidence regarding the quantity and quality of protein that can be recommended for living kidney donors and the same for sodium. Plant Dominant (PLADO) diets, Dietary Approaches to Stop Hypertension (DASH), Mediterranean, and vegetarian diets may be favorable for living kidney donors with solitary kidney but the evidence is still lacking.

SUMMARY

Although dietary interventions may provide benefits and kidney health for living kidney donors, further studies including clinical trials are required to incorporate them into clinical practice guidelines.

Vegetable Preference and Prediction of Proteinuria: A Retrospective Cohort Study

INTRODUCTION

Little information is available about the association between vegetable preference and chronic kidney disease.

METHODS

This retrospective cohort study included 10,819 university workers in Japan who underwent their annual health checkups between January 2005 and March 2013. According to a question "Do you like vegetables"? with 3 possible answers of "I like vegetables," "I like vegetables somewhat," or "I dislike vegetables," 2,831, 2,249, and 104 male workers and 3,902, 1,648, and 85 female workers were classified into the "like," "somewhat," and "dislike" groups, respectively. An association between vegetable preference and incidence of proteinuria (dipstick urinary protein ≥1+) was assessed using Cox proportional-hazards models adjusted for clinically relevant factors.

RESULTS

During the median observational period of 5.0 years, the incidence of proteinuria was observed in 650 (12.7%) male and 789 (14.1%) female workers. Among male workers, the "dislike" group had a significantly higher risk of proteinuria (multivariable-adjusted hazard ratio of "like," "somewhat," and "dislike" groups: 1.00 [reference], 1.05 [0.90-1.23], and 1.59 [1.01-2.50], respectively). Among female workers, vegetable preference was associated with the incidence of proteinuria in a dose-dependent manner (1.00 [reference], 1.20 [1.04-1.40], 1.95 [1.26-3.02], respectively).

CONCLUSION

"Do you like vegetables"? was a clinically useful tool to identify subjects vulnerable to proteinuria.

A Plant-Centered Diet and Markers of Early Chronic Kidney Disease during Young to Middle Adulthood: Findings from the Coronary Artery Risk Development in Young Adults (CARDIA) Cohort

BACKGROUND

Few studies have evaluated whether plant-centered diets prevent progression of early stage chronic kidney disease (CKD).

OBJECTIVES

We examined the association between plant-centered diet quality and early CKD markers.

METHODS

We prospectively examined 2869 black and white men and women in the Coronary Artery Risk Development in Young Adults Study free of diagnosed kidney failure in 2005-2006 [examination year 20 (Y20); mean age: 45.3 ± 3.6  y]. CKD marker changes from Y20 to 2015-2016 (Y30) were considered, including estimated glomerular filtration rate (eGFR; serum creatinine), urinary albumin-to-creatinine ratio (ACR), and both. Diet was assessed through interviewer-administered diet histories at Y0, Y7, and Y20, and plant-centered diet quality was quantified with the A Priori Diet Quality Score (APDQS). Linear regression models were used to examine the association of APDQS and subsequent 10-y changes in CKD markers.

RESULTS

After adjustment for sociodemographic, behavioral, and diet factors, we found that higher APDQS was related to less adverse changes in CKD markers in the subsequent 10-y period. Compared with the lowest APDQS quintile, the highest quintile was associated with an attenuated increase in lnACR (-0.25 mg/g; 95% CI: -0.37, -0.13 mg/g; P-trend < 0.001), whereas the highest quintile was associated with an attenuated decrease in eGFR (4.45 mL·min-1·1.73 m-2; 95% CI: 2.46, 6.43 mL·min-1·1.73 m-2). There was a 0.50 lower increase in combined CKD markers [ln(ACR) z score - eGFR z score] when comparing the extreme quintiles. Associations remained similar after further adjustment for hypertension, diabetes, and obesity as potential mediating factors. The attenuated worsening CKD marker changes associated with higher APDQS strengthened across increasing initial CKD category; those with the best diet and microalbuminuria in Y10-Y20 returned to high normal albuminuria (all P-interaction < 0.001).

CONCLUSIONS

Individuals who consumed plant-centered, high-quality diets were less likely to experience deterioration of kidney function through midlife, especially among participants with initial stage characterized as mild CKD.

Adherence to healthy dietary pattern and risk of kidney disease: a systematic review and meta-analysis of observational studies

Epidemiological studies show that adherence to healthy dietary patterns may be associated with a lower risk of decline in kidney function. However, existing evidence has not been quantitatively gathered. Pertinent observational studies investigating the association of adherence to a healthy dietary pattern, either priori-defined dietary pattern/indices or data-driven dietary patterns, with risk of kidney disease in the general population were identified by searching Medline and Scopus databases to May 28, 2018. A random-effects meta-analysis was applied. The analysis included eight prospective cohorts (5734 cases among 569,688 participants) and five cross-sectional studies (1955 cases among 16,614 participants). Higher adherence to a healthy dietary pattern (either priori-defined or data-driven dietary patterns) was associated with a 28% lower risk of kidney disease in the analysis of prospective cohort studies (RR = 0.72, 95 % CI = 0.58, 0.86; I² = %71, n = 8). A subgroup analysis based on definition of healthy dietary pattern resulted in significant inverse association only in the subgroup of Dietary Approaches to Stop Hypertension dietary pattern (RR: 0.74, 95 % CI: 0.54, 0.93; I² = 73%, n = 5). A dose-response analysis indicated a monotonic inverse association between adherence to the Dietary Approaches to Stop Hypertension dietary pattern with risk of kidney disease. A 32% lower risk was observed in the analysis of cross-sectional studies (OR: 0.68, 95 %CI: 0.53, 0.83, I² = 0%, n = 5). The findings suggest that higher adherence to a healthy dietary pattern is associated with a lower risk of kidney disease.

Major dietary patterns in relation to preeclampsia among Iranian pregnant women: a case-control study

Background: Preeclampsia is a pregnancy disorder that increases the risk of prenatal and maternal complications. Therefore, prevention of preeclampsia requires identifying its preventable risk factors such as dietary patterns.Objective: This study aimed to investigate the relationship between the major dietary patterns and preeclampsia.Study design: In this case-control study, the dietary patterns of a total of 510 pregnant women were investigated. Data on their dietary intake, sociodemographics, and daily physical activity levels were collected using a 198 item semi-quantitative food frequency questionnaire, a sociodemographic questionnaire, and a physical activity questionnaire, respectively. To identify the major dietary patterns and to model the relationship between dietary patterns and preeclampsia, factor analysis and unconditional logistic regression were employed, respectively. The three major dietary patterns identified were as follows: healthy dietary pattern (i.e. high in fruits, low-fat dairy, dried fruits, nuts, vegetables, fruit juice, liquid oil, and tomatoes), western dietary pattern (i.e. high in red meat, processed meat, fried potatoes, and pickles), and Iranian traditional dietary pattern (i.e. high in eggs, potatoes, and legumes).Results: After adjustment for confounding factors, we found that with an increase in the healthy dietary pattern score, the odds of preeclampsia were reduced to 87.5% (OR = 0.125, 95%CI: 0.070-0.221, p < .001); with an increase in the western dietary pattern score, the odds of preeclampsia were increased 5.99 times (OR = 5.99, 95%CI: 3.414-10.53, p < .001); and with an increase in the Iranian traditional dietary pattern score, the odds of preeclampsia were reduced to 81.7% (OR = 0.183, 95%CI: 0.109-0.308, p < .001).Conclusion: The findings showed that the western dietary pattern had a direct relationship and the healthy and Iranian traditional patterns had a reverse relationship with preeclampsia.

Adherence to low-sodium Dietary Approaches to Stop Hypertension-style diet may decrease the risk of incident chronic kidney disease among high-risk patients: a secondary prevention in prospective cohort study

Background

Considering the fact that subjects with dysglycemia, dyslipidemia or high blood pressure are at high risk for chronic kidney disease (CKD), long-term adherence to the Dietary Approaches to Stop Hypertension (DASH)-style diet may contribute to the prevention of CKD. This study, examined the association between adherence to the low-sodium DASH-style diet and incident CKD among high-risk adults over 3 years of follow-up.

Methods

In this prospective cohort study (followed up for 3 years, 2012-15), we selected 1100 subjects with dysglycemia, 2715 with dyslipidemia and 2089 with high blood pressure, all of whom were free of CKD at baseline (2009-11) in a subgroup of the Tehran Lipid and Glucose Study. The low-sodium DASH-style diet was designed based on eight foods and nutrients using a food frequency questionnaire. Estimated glomerular filtration rate (eGFR) was calculated and CKD was defined as eGFR <60 mL/min/1.73 m2.

Results

After 3 years of follow-up, among subjects with dysglycemia, dyslipidemia or high blood pressure, the rate of incident CKD was ∼16%. In multivariable-adjusted analyses for participants in the highest compared with the lowest quartile of the low-sodium DASH-style diet score, the odds ratio was 0.58 [95% confidence interval (CI) 0.36-0.92] for subjects with dysglycemia, 0.64 (95% CI 0.48-0.87) for subjects with dyslipidemia and 0.62 (95% CI 0.44-0.87) for subjects with high blood pressure.

Conclusions

Higher adherence to the low-sodium DASH-style diet might be associated with a lower risk of incident CKD among high-risk adults, highlighting the importance of adherence to the low-sodium DASH-style diet in substantially reducing both the occurrence of CKD and the burden imposed by it in the future.

Plant-Based Diets and Incident CKD and Kidney Function

BACKGROUND AND OBJECTIVES

The association between plant-based diets, incident CKD, and kidney function decline has not been examined in the general population. We prospectively investigated this relationship in a population-based study, and evaluated if risk varied by different types of plant-based diets.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Analyses were conducted in a sample of 14,686 middle-aged adults enrolled in the Atherosclerosis Risk in Communities study. Diets were characterized using four plant-based diet indices. In the overall plant-based diet index, all plant foods were positively scored; in the healthy plant-based diet index, only healthful plant foods were positively scored; in the provegetarian diet, selected plant foods were positively scored. In the less healthy plant-based diet index, only less healthful plant foods were positively scored. All indices negatively scored animal foods. We used Cox proportional hazards models to study the association with incident CKD and linear mixed models to examine decline in eGFR, adjusting for confounders.

RESULTS

During a median follow-up of 24 years, 4343 incident CKD cases occurred. Higher adherence to a healthy plant-based diet (HR comparing quintile 5 versus quintile 1 [HRQ5 versus Q1], 0.86; 95% confidence interval [95% CI], 0.78 to 0.96; P for trend =0.001) and a provegetarian diet (HRQ5 versus Q1, 0.90; 95% CI, 0.82 to 0.99; P for trend =0.03) were associated with a lower risk of CKD, whereas higher adherence to a less healthy plant-based diet (HRQ5 versus Q1, 1.11; 95% CI, 1.01 to 1.21; P for trend =0.04) was associated with an elevated risk. Higher adherence to an overall plant-based diet and a healthy plant-based diet was associated with slower eGFR decline. The proportion of CKD attributable to lower adherence to healthy plant-based diets was 4.1% (95% CI, 0.6% to 8.3%).

CONCLUSIONS

Higher adherence to healthy plant-based diets and a vegetarian diet was associated with favorable kidney disease outcomes.

KDOQI US Commentary on the 2017 ACC/AHA Hypertension Guideline

Hypertension is a modifiable risk factor for cardiovascular morbidity and mortality and reduction of elevated blood pressure (BP) remains an important intervention for slowing kidney disease progression. Over the past decade, the most appropriate BP target for initiation and titration of BP-lowering medications has been an area of intense research and debate within the clinical community. In 2017, the American College of Cardiology and the American Heart Association (ACC/AHA) in conjunction with several other professional societies released new hypertension guidelines based on data from a systematic review of clinical trials and observational data. While many of the recommendations in the ACC/AHA hypertension guideline are relevant to nephrology practice, BP targets and management strategies for patients receiving dialysis are not discussed. This Kidney Disease Outcomes Quality Initiative (KDOQI) commentary focuses largely on recommendations from the ACC/AHA hypertension guidelines that are pertinent to individuals at risk of chronic kidney disease or with non-dialysis-dependent chronic kidney disease. This KDOQI commentary also includes a brief discussion of the consensus statement regarding hypertension diagnosis and management for adults receiving maintenance dialysis published by the European Renal and Cardiovascular Medicine Working Group of the European Renal Association-European Dialysis and Transplant Association (ERA-EDTA) and the Hypertension and the Kidney working group of the European Society of Hypertension. Overall, we support the vast majority of the ACC/AHA recommendations and highlight select areas in which best diagnosis and treatment options remain controversial.

Urinary Potassium Excretion and Progression of CKD

BACKGROUND AND OBJECTIVES

Data on whether low or high urinary potassium excretion is associated with poor kidney outcome have been conflicting. The aim of this study was to clarify the association between urinary potassium excretion and CKD progression.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We investigated the relationship between lower urinary potassium excretion and CKD progression and compared three urinary potassium indices among 1821 patients from the Korean Cohort Study for Outcome in Patients with CKD. Urinary potassium excretion was determined using spot urinary potassium-to-creatinine ratio, spot urinary potassium concentration, and 24-hour urinary potassium excretion. Patients were categorized into four groups according to quartiles of each urinary potassium excretion metric. The study end point was a composite of a ≥50% decrease in eGFR from baseline values and ESKD.

RESULTS

During 5326 person-years of follow-up, the primary outcome occurred in 392 (22%) patients. In a multivariable cause-specific hazard model, lower urinary potassium-to-creatinine ratio was associated with higher risk of CKD progression (adjusted hazard ratio, 1.47; 95% confidence interval, 1.01 to 2.12) comparing the lowest quartile with the highest quartile. Sensitivity analyses with other potassium metrics also showed consistent results in 855 patients who completed 24-hour urinary collections: adjusted hazard ratios comparing the lowest quartile with the highest quartile were 3.05 (95% confidence interval, 1.54 to 6.04) for 24-hour urinary potassium excretion, 1.95 (95% confidence interval, 1.05 to 3.62) for spot urinary potassium-to-creatinine ratio, and 3.79 (95% confidence interval, 1.51 to 9.51) for spot urinary potassium concentration.

CONCLUSIONS

Low urinary potassium excretion is associated with progression of CKD.

Dietary Fiber Intake (Supplemental or Dietary Pattern Rich in Fiber) and Diabetic Kidney Disease: A Systematic Review of Clinical Trials

Fiber intake is associated with better glycemic control being an important nonpharmacologicaltreatment for diabetes (DM). We hypothesize that a dietary fiber intake can bringbenefits to diabetic kidney disease (DKD), improving renal outcomes. This systematic review aimedto evaluate the effect of dietary fiber (supplemental or dietary pattern rich in fiber) on DKD. Wesearched six databases to identify clinical trials that reported fiber intake and renal outcomes(albuminuria, proteinuria, estimated glomerular filtration rate (eGFR) dialysis) in patients with DM.From 1814 studies, 48 papers were fully evaluated. In the end, seven trials (161 patients, aged 58.3years, 49% females) were included. The studies were organized into three categories (vegetarian,Dietary Approaches to Stop Hypertension (DASH) diet, and fiber supplement), two evaluatedsupplements and five dietary patterns. Vegetarian diet reduced albuminuria in three trials, two inpatients with type 1 DM and one in patients with type 2 DM; and one study demonstrated a change inthe eGFR in type 1 DM. The individual quality of the studies was low/uncertain. A vegetarian dietarypattern may have a beneficial effect on these renal outcomes. However, the individual effect of theintake of fiber on DKD not was possible to be evaluated.

Sociodemographic and Kidney Disease Correlates of Nutrient Intakes Among Urban African Americans With Uncontrolled Hypertension

OBJECTIVE

The objective of this study was to determine the association between sociodemographic factors and intakes of 4 nutrients and associations between intakes and markers of kidney disease to identify opportunities to improve outcomes among clinically high-risk African Americans.

DESIGN AND METHODS

We conducted a cross-sectional study of baseline data from the Achieving Blood Pressure Control Together study, a randomized controlled trial of 159 African Americans (117 females) with uncontrolled hypertension in Baltimore MD. To determine the association between sociodemographic factors and nutrient intakes, we constructed linear and logistic regression models. Using logistic regression, we determined the association between below-median nutrient intakes and kidney disease. Our outcomes of interest were daily intakes of vitamin C, magnesium, dietary fiber, and potassium as estimated by the Block Fruit-Vegetable-Fiber Screener and kidney disease defined as estimated glomerular filtration rate <60 mL/min per 1.73 m2 or urinary albumin-to-creatinine ratio >=30 mg/g.

SETTING AND SUBJECTS

Baseline data from the Achieving Blood Pressure Control Together study, a randomized controlled trial of 159 African Americans (117 females) with uncontrolled hypertension, were obtained.

METHODS

To determine the association between sociodemographic factors and nutrient intakes, we constructed linear and logistic regression models. Using logistic regression, we determined the association between below-median nutrient intakes and kidney disease.

MAIN OUTCOME MEASURES

Our outcomes of interest were daily intakes of vitamin C, magnesium, dietary fiber, and potassium as estimated by the Block Fruit-Vegetable-Fiber Screener and kidney disease defined as estimated glomerular filtration rate <60 mL/min per 1.73 m² or urinary albumin-to-creatinine ratio ≥30 mg/g.

RESULTS

Overall, compared to Institute of Medicine recommendations, participants had lower intakes of magnesium, fiber, and potassium but higher vitamin C intakes. For females, sociodemographic factors that significantly associated with lower intake of the 4 nutrients were older age, obesity, lower health numeracy, and lesser educational attainment. For males, none of the sociodemographic factors were significantly associated with nutrient intakes. Below-median intake was significantly associated with albumin-to-creatinine ratio ≥30 (adjusted odds ratio [95% confidence interval]: 3.4 [1.5, 7.8] for vitamin C; 3.6 [1.6, 8.4] for magnesium; 2.9 [1.3, 6.5] for fiber; 3.6 [1.6, 8.4] for potassium), but not with estimated glomerular filtration rate <60.

CONCLUSION

African Americans with uncontrolled hypertension may have low intakes of important nutrients, which could increase their risk of chronic kidney disease. Tailored dietary interventions for African Americans at high risk for chronic kidney disease may be warranted.

A Systematic Review of Renal Health in Healthy Individuals Associated with Protein Intake above the US Recommended Daily Allowance in Randomized Controlled Trials and Observational Studies

A systematic review was used to identify randomized controlled trials (RCTs) and observational epidemiologic studies (OBSs) that examined protein intake consistent with either the US RDA (0.8 g/kg or 10-15% of energy) or a higher protein intake (≥20% but <35% of energy or ≥10% higher than a comparison intake) and reported measures of kidney function. Studies (n = 26) of healthy, free-living adults (>18 y old) with or without metabolic disease risk factors were included. Studies of subjects with overt disease, such as chronic kidney, end-stage renal disease, cancer, or organ transplant, were excluded. The most commonly reported variable was glomerular filtration rate (GFR), with 13 RCTs comparing GFRs obtained with normal and higher protein intakes. Most (n = 8), but not all (n = 5), RCTs reported significantly higher GFRs in response to increased protein intake, and all rates were consistent with normal kidney function in healthy adults. The evidence from the current review is limited and inconsistent with regard to the role of protein intake and the risk of kidney stones. Increased protein intake had little or no effect on blood markers of kidney function. Evidence reported here suggests that protein intake above the US RDA has no adverse effect on blood pressure. All included studies were of moderate to high risk of bias and, with the exception of 2 included cohorts, were limited in duration (i.e. <6 mo). Data in the current review are insufficient to determine if increased protein intake from a particular source, i.e., plant or animal, influences kidney health outcomes. These data further indicate that, at least in the short term, higher protein intake within the range of recommended intakes for protein is consistent with normal kidney function in healthy individuals.

Fresh fruit consumption and risk of incident albuminuria among rural Chinese adults: A village-based prospective cohort study

Background

Recent studies showed that increased fresh fruit consumption is significantly associated with lower risks of diabetes, hypertension, and cardiovascular disease (CVD); other studies suggested that albuminuria is associated with diabetes, hypertension, and CVD. Therefore, we hypothesized that lower fresh fruit consumption is associated with higher risk of incident albuminuria among Chinese adults in rural areas, where fresh fruit consumption level is very low and prevalence of albuminuria is high.

Methods

We tested the hypothesis in a village-based cohort study of 3574 participants aged ≥ 30 years from the Handan Eye Study conducted from 2006 to 2013. Albuminuria was defined as urinary albumin-to-creatinine ratio ≥ 30 mg/g.

Results

Overall, 35.4% of the participants never or rarely consumed fresh fruits, and 33.9, 21.6, and 9.1% consumed fresh fruits 1–3 times/month, 1–2 times/week, and ≥ 3 times/week, respectively. During a median follow-up period of 5.6 years, albuminuria developed in 17.6% (n = 629) of the participants. Compared with participants who consumed fresh fruits ≥ 3 times/week, the multivariable adjustment odds ratios (ORs) for incident albuminuria associated with fruit consumption 1–2 times/week, 1–3 times/month, and no or rare consumption were 1.58 (95% confidence intervals (CI), 1.05–2.40), 1.74 (95% CI, 1.17–2.58), and 1.78 (95% CI, 1.20–2.64), respectively. After excluding participants with diabetes, the association remained significant.

Conclusions

Lower fresh fruit consumption was significantly associated with higher risk of incident albuminuria, and fresh fruit consumption frequency could be an essential intervention target to prevent albuminuria in rural China.

Prevention and treatment of hyperphosphatemia in chronic kidney disease

Hyperphosphatemia has consistently been shown to be associated with dismal outcome in a wide variety of populations, particularly in chronic kidney disease (CKD). Compelling evidence from basic and animal studies elucidated a range of mechanisms by which phosphate may exert its pathological effects and motivated interventions to treat hyperphosphatemia. These interventions consisted of dietary modifications and phosphate binders. However, the beneficial effects of these treatment methods on hard clinical outcomes have not been convincingly demonstrated in prospective clinical trials. In addition, exposure to high amounts of dietary phosphate may exert untoward actions even in the absence of overt hyperphosphatemia. Based on this concept, it has been proposed that the same interventions used in CKD patients with normal phosphate concentrations be used in the presence of hyperphosphatemia to prevent rise of phosphate concentration and as an early intervention for cardiovascular risk. This review describes conceptual models of phosphate toxicity, summarizes the evidence base for treatment and prevention of hyperphosphatemia, and identifies important knowledge gaps in the field.

Ambulatory blood pressure in the dash diet trial: Effects of race and albuminuria

We evaluated whether low-grade albuminuria or black race modulates ambulatory blood pressure (BP) or nocturnal BP response to the DASH diet. Among 202 adults enrolled in the DASH multicenter trial who were fed the DASH or control diet for 8 weeks, reductions in 24-hour daytime and nighttime SBP and DBP were significantly larger for DASH compared to control. Median changes in nocturnal BP dipping were not significant. Compared to urine albumin excretion of <7 mg/d, ≥7 mg/d was associated with larger significant median reductions in 24-hour SBP (-7.3 vs -3.1 mm Hg), all measures of DBP (24-hour: -5.9 vs -1.8 mm Hg; daytime: -9.9 vs -4.0 mm Hg; nighttime -9.0 vs -2.0 mm Hg), and with increased nocturnal SBP dipping (2.3% vs -0.5%). Black race was associated with larger median reduction in 24-hour SBP only (-5.5 vs -2.4 mm Hg). This analysis suggests greater effect of DASH on ambulatory BP in the presence of low-grade albuminuria.

Western Dietary Pattern Is Associated with Irritable Bowel Syndrome in the French NutriNet Cohort

Background: Diet appears to play a key role in the pathogenesis of the irritable bowel syndrome (IBS). Some dietary patterns (DP) could increase the risk of triggering or worsening IBS symptoms. This cross-sectional study aimed to assess the association between a posteriori derived DP and IBS in a large French population, the web-based NutriNet-Santé cohort. Methods: Study population included participants of the NutriNet-Santé study who completed a questionnaire based on Rome III criteria assessing IBS. A principal component analysis (PCA) was performed to identify major DPs based on 29 food groups' consumption. Associations between DP quintiles and IBS were investigated with multivariable logistic regressions. Results: 44,350 participants were included, with 2423 (5.5%) presenting IBS. Three major DP were extracted using PCA, "healthy," "western," and "traditional." After adjustments on confounders, the "western" DP was positively associated with IBS (OR _{Q5 vs. Q1} = 1.38, 95% CI 1.19-1.61, p trend < 0.0001) and the "traditional" DP was positively associated with IBS in women (OR _{Q5 vs. Q1} = 1.29 95% CI 1.08-1.54, p trend = 0.001). Conclusions: In this study, a "western" DP-highly correlated with the consumption of fatty and sugary products and snacks-was associated with a moderate increased risk of IBS.

Dietary Approaches in the Management of Diabetic Patients with Kidney Disease

Chronic kidney disease (CKD) is one of the most prevalent complications of diabetes, and patients with diabetic kidney disease (DKD) have a substantially higher risk of cardiovascular disease and death compared to their non-diabetic CKD counterparts. In addition to pharmacologic management strategies, nutritional and dietary interventions in DKD are an essential aspect of management with the potential for ameliorating kidney function decline and preventing the development of other end-organ complications. Among DKD patients with non-dialysis dependent CKD, expert panels recommend lower dietary protein intake of 0.8 g/kg of body weight/day, while higher dietary protein intake (>1.2 g/kg of body weight/day) is advised among diabetic end-stage renal disease patients receiving maintenance dialysis to counteract protein catabolism, dialysate amino acid and protein losses, and protein-energy wasting. Carbohydrates from sugars should be limited to less than 10% of energy intake, and it is also suggested that higher polyunsaturated and monounsaturated fat consumption in lieu of saturated fatty acids, trans-fat, and cholesterol are associated with more favorable outcomes. While guidelines recommend dietary sodium restriction to less than 1.5–2.3 g/day, excessively low sodium intake may be associated with hyponatremia as well as impaired glucose metabolism and insulin sensitivity. As patients with advanced DKD progressing to end-stage renal disease may be prone to the “burnt-out diabetes” phenomenon (i.e., spontaneous resolution of hypoglycemia and frequent hypoglycemic episodes), further studies in this population are particularly needed to determine the safety and efficacy of dietary restrictions in this population.

Dietary Phosphorus Intake and the Kidney

Although phosphorus is an essential nutrient required for multiple physiological functions, recent research raises concerns that high phosphorus intake could have detrimental effects on health. Phosphorus is abundant in the food supply of developed countries, occurring naturally in protein-rich foods and as an additive in processed foods. High phosphorus intake can cause vascular and renal calcification, renal tubular injury, and premature death in multiple animal models. Small studies in human suggest that high phosphorus intake may result in positive phosphorus balance and correlate with renal calcification and albuminuria. Although serum phosphorus is strongly associated with cardiovascular disease, progression of kidney disease, and death, limited data exist linking high phosphorus intake directly to adverse clinical outcomes. Further prospective studies are needed to determine whether phosphorus intake is a modifiable risk factor for kidney disease.

Healthy Dietary Patterns and Risk of Mortality and ESRD in CKD: A Meta-Analysis of Cohort Studies

BACKGROUND AND OBJECTIVES

Patients with CKD are advised to follow dietary recommendations that restrict individual nutrients. Emerging evidence indicates overall eating patterns may better predict clinical outcomes, however, current data on dietary patterns in kidney disease are limited.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

This systematic review aimed to evaluate the association between dietary patterns and mortality or ESRD among adults with CKD. Medline, Embase, and reference lists were systematically searched up to November 24, 2015 by two independent review authors. Eligible studies were longitudinal cohort studies reporting the association of dietary patterns with mortality, cardiovascular events, or ESRD.

RESULTS

A total of seven studies involving 15,285 participants were included. Healthy dietary patterns were generally higher in fruit and vegetables, fish, legumes, cereals, whole grains, and fiber, and lower in red meat, salt, and refined sugars. In six studies, healthy dietary patterns were consistently associated with lower mortality (3983 events; adjusted relative risk, 0.73; 95% confidence interval, 0.63 to 0.83; risk difference of 46 fewer (29-63 fewer) events per 1000 people over 5 years). There was no statistically significant association between healthy dietary patterns and risk of ESRD (1027 events; adjusted relative risk, 1.04; 95% confidence interval, 0.68 to 1.40).

CONCLUSIONS

Healthy dietary patterns are associated with lower mortality in people with kidney disease. Interventions to support adherence to increased fruit and vegetable, fish, legume, whole grain, and fiber intake, and reduced red meat, sodium, and refined sugar intake could be effective tools to lower mortality in people with kidney disease.

Low Rice Intake Is Associated with Proteinuria in Participants of Korea National Health and Nutrition Examination Survey

Little is known about the risk factors of proteinuria in the Asian population. On the basis of the association between rice intake patterns and chronic diseases, we hypothesized that rice intake patterns are associated with proteinuria in the Asian population. Data, including data regarding rice intake frequency and dipstick urinalysis results, from the Korea National Health and Nutrition Examination Survey in 1998, 2001, 2005, and 2007 were analyzed. The study involved 19,824 participants who were older than 20 years of age. Low rice intake was defined as consumption of rice ≤ 1 time/day. Proteinuria was defined as dipstick urinalysis protein ≥ 1 positive. Among the 19,824 participants, the prevalence of low rice intake and proteinuria were 17.3% and 2.9%, respectively. The low rice intake group showed a higher rate of proteinuria than the non-low rice intake group did (3.8% vs. 2.7%, P < 0.001). In multivariate logistic regression analysis, the odds ratio (OR) of low rice intake for proteinuria was 1.54 (95% confidence interval (CI): 1.25-1.89; P < 0.001). Low rice intake was also independently associated with high blood pressure (OR: 1.43, 95% CI: 1.31-1.56; P < 0.001) and diabetes (OR: 1.43, 95% CI: 1.27-1.62; P < 0.001). In conclusion, low rice intake was found to be independently associated with proteinuria in the Asian population, which might have been affected by the associations of low rice intake with high blood pressure and diabetes. Future prospective studies are needed to confirm the results of this study.

DASH dietary pattern and chronic kidney disease in elderly Korean adults

BACKGROUND/OBJECTIVES

Dietary patterns are linked to risk and outcomes in chronic kidney disease (CKD). Dietary intake varies by race, region and age. The relationship between a Dietary Approaches to Stop Hypertension (DASH) diet and CKD in elderly Koreans is unclear.

SUBJECTS/METHODS

We conducted cross-sectional analyses of 2408 community-dwelling elderly participants from the Korean National Health and Nutrition Examination Survey (2011-2012). DASH dietary patterns for six nutrients (protein, fiber, calcium, potassium, total fat and sodium) were collected by 24 h recall. DASH-US (based on the US recommendations) and DASH-KQ (Korean quartile) scores were generated by summing the scores for the six nutrients. Multivariate logistic regression analysis was used to calculate odds ratio (OR) for the association between a DASH diet and CKD.

RESULTS

Mean subject age was 72.4±5.1 years, 13.9% had CKD and 23.8% had diabetes. Protein, fiber, calcium and potassium intake was lower in CKD than non-CKD participants. In multivariate logistic regression analysis adjusted for age, sex, body mass index, comorbid conditions and other factors, a high DASH score was associated with a low odds for CKD based on DASH-US (OR=0.78, 95% confidence interval (CI), 0.65-0.94, P=0.009) and DASH-KQ (OR=0.95, 95% CI, 0.91-0.99, P=0.022). In six nutrients of DASH diet, high fiber intake showed a low odds for CKD in the DASH-KQ model (P for trend=0.010).

CONCLUSIONS

Our findings suggest that higher adherence to a DASH diet and higher fiber intake are associated with lower odds of CKD in elderly Koreans. These results should be corroborated through longitudinal studies of the association between a DASH diet and high-fiber diet on the risk of developing CKD.

Dietary Patterns and Clinical Outcomes in Chronic Kidney Disease: The CKD.QLD Nutrition Study

OBJECTIVE

Emerging evidence suggests that dietary patterns are associated with survival in people with chronic kidney disease (CKD). This study evaluated the relationship between dietary habits and renal-related clinical outcomes in an established CKD cohort.

DESIGN

Prospective cohort study.

SETTING

Three outpatient nephrology clinics in Queensland, Australia.

SUBJECTS

A total of 145 adult patients with Stage 3 or 4 CKD (estimated glomerular filtration rate 15-59 mL/minute/1.73 m²).

INTERVENTION

Dietary intake was measured using 24-hour recall and the HeartWise Dietary Habits Questionnaire (DHQ), which evaluates 10 components of dietary patterns in relation to cooking habits and intake of food groups.

MAIN OUTCOME MEASURE

The primary outcome was a composite end point of all-cause mortality, commencement of dialysis, and doubling of serum creatinine. Secondary outcome was all-cause mortality alone. Multivariate cox regression analyses calculated hazard ratios (HRs) for associations between DHQ domains and occurrence of composite outcome and adjusted for confounders, including comorbidities and renal function.

RESULTS

Over a median follow-up of 36 months, 32% (n = 47) reached the composite end point, of which 21% died (n = 30). Increasing DHQ score was associated with a lower risk of the composite end point with increasing intake of fruits and vegetables (HR: 0.61; 95% CI, 0.39-0.94) and limiting alcohol consumption (HR, 0.79; 95% CI: 0.65-0.96). For the secondary outcome of all-cause mortality, there was a significant association with adequate intake of fruits and vegetables (HR: 0.35; 95% CI, 0.15-0.83).

CONCLUSION

Healthy dietary patterns consisting of adequate fruits and vegetables and limited alcohol consumption are associated with a delay in CKD progression and improved survival in patients with Stage 3 or 4 CKD.

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.

What an anticardiovascular diet should be in 2015

PURPOSE OF REVIEW

Given scientific and public debate about optimal diet to prevent cardiovascular disease, and interest in diet and other chronic diseases, we propose that following a few simple dietary principles would reduce chronic disease incidence.

RECENT FINDINGS

Nutrition research has been criticized for focusing on individual nutrients and foods, treated like drug therapy. With a few important exceptions, clinical trials of supplemental nutrients have not shown benefit. Although highly specific nutrition information is elusive, diet patterns have provided consistent answers, important for public health. Observational cohort studies have found that some dietary patterns are reported with high reliability over long periods and predict future cardiovascular and other inflammatory-related diseases. Two randomized clinical trials confirmed this finding. There are many common features of Mediterranean and prudent diets, particularly the plant-centered aspect, coupled with variety of foods eaten. A dietary pattern characterized by high fruit, vegetable, legume, whole grain, nut, berry, seed, and fish intakes, and possibly by intakes of dairy, coffee, tea, chocolate, and alcohol (not in excess), but low meat and detrimentally processed foods is associated with reduced incidence of cardiovascular disease and rates of noncardiovascular, noncancer chronic inflammatory-related mortality.

SUMMARY

A plant-centered diet may be broadly recommended.

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.

Association of a reduction in central obesity and phosphorus intake with changes in urinary albumin excretion: the PREMIER study

BACKGROUND

Excess adiposity and dietary factors may be important determinants of urinary albumin excretion (UAE).

STUDY DESIGN

Observational analysis of PREMIER, a randomized trial designed to lower blood pressure using behavioral interventions (counseling on weight loss, healthy diet, and exercise).

SETTING & PARTICIPANTS

481 participants with normal kidney function who provided adequate 24-hour urine collections at baseline and 6 months.

PREDICTORS

Change in waist circumference; 24-hour urine sodium, potassium, and phosphorus excretion; and protein intake estimated from urea nitrogen.

OUTCOMES & MEASUREMENTS

The primary outcome was change in log-transformed 24-hour UAE over 6 months.

RESULTS

After 6 months, the proportion of individuals with UAE ≥10 mg/d decreased from 18.7% to 12.7% (P < 0.001). Changes in mean waist circumference (-4.2 ± 6.6 [SD] cm), 24-hour excretion of sodium (-28.2 ± 71.7 mmol/d), potassium (+8.4 ± 27.8 mmol/d), phosphorus (-27.7 ± 314.1 mg/d), and protein intake (-1.7 ± 19.4 g/d) were observed. After adjustment for relevant covariates, the following variables were associated significantly with reduction in ln(UAE) in separate models: decrease in waist circumference (P = 0.001), decrease in 24-hour urine phosphorus excretion (P < 0.001), and decrease in protein intake (P = 0.01). In a multivariable model including these 3 predictors, decreases in waist circumference (P = 0.002) and 24-hour urine phosphorus excretion (P = 0.03), but not change in protein intake (P = 0.5), remained associated significantly with reduction in ln(UAE). These associations remained significant even after adjustment for changes in blood pressure and insulin resistance. Baseline UAE and metabolic syndrome modified the relationship of waist circumference with ln(UAE); specifically, individuals with higher UAE and baseline metabolic syndrome experienced greater reductions in ln(UAE) from decreases in waist circumference.

LIMITATIONS

Observational study with potential for confounding.

CONCLUSIONS

In adults with normal kidney function, decreases in waist circumference and 24-hour urine phosphorus excretion are associated with reductions in UAE. These findings support the rationale for clinical trials to determine whether reducing dietary phosphorus intake or waist circumference could prevent chronic kidney disease or slow its progression.

Lifestyle-related factors, obesity, and incident microalbuminuria: the CARDIA (Coronary Artery Risk Development in Young Adults) study

BACKGROUND

Modifiable lifestyle-related factors are associated with risk of coronary heart disease and may also influence kidney disease risk.

STUDY DESIGN

Community-based prospective cohort study.

SETTING & PARTICIPANTS

2,354 African American and white participants aged 28-40 years without baseline microalbuminuria or estimated glomerular filtration rate <60 mL/min/1.73 m² recruited from 4 US centers: Birmingham, AL; Chicago, IL; Minneapolis, MN; and Oakland, CA.

FACTORS

Current smoking, physical activity, fast food habits, obesity, and diet quality, which was based on 8 fundamental components of the Dietary Approaches to Stop Hypertension (DASH) diet, including increased intake of fruits, vegetables, low-fat dairy products, whole grains, and nuts and legumes and reduced intake of sodium, sugar-sweetened beverages, and red and processed meats.

OUTCOMES & MEASUREMENTS

Spot urine albumin-creatinine ratios were obtained at baseline (1995-1996) and three 5-year follow-up examinations (5, 10, and 15 years' follow-up). Incident microalbuminuria was defined as the presence of age- and sex-adjusted albumin-creatinine ratio ≥25 mg/g at 2 or more of the successive follow-up examinations.

RESULTS

During the 15-year follow-up, 77 (3.3%) individuals developed incident microalbuminuria. After multivariable adjustment, poor diet quality (OR, 2.0; 95% CI, 1.1-3.4) and obesity (OR, 1.9; 95% CI, 1.1-3.3) were associated significantly with microalbuminuria; current smoking (OR, 1.6; 95% CI, 0.9-2.8) was associated with microalbuminuria, although the CI crossed 1.0. Neither low physical activity (OR, 1.0; 95% CI, 0.5-1.8) nor fast food consumption (OR, 1.2; 95% CI, 0.7-2.3) was associated with microalbuminuria. Compared with individuals with no unhealthy lifestyle-related factors (poor diet quality, current smoking, and obesity), adjusted odds of incident microalbuminuria were 131%, 273%, and 634% higher for the presence of 1 (OR, 2.3; 95% CI, 1.3-4.3), 2 (OR, 3.7; 95% CI, 1.8-7.7), and 3 (OR, 7.3; 95% CI, 2.1-26.1) unhealthy lifestyle-related factors.

LIMITATIONS

Self-reported dietary history and physical activity, low number of outcomes.

CONCLUSIONS

Consuming an unhealthy diet and obesity are associated with incident microalbuminuria.

Improvement of the metabolic syndrome profile by soluble fibre - guar gum - in patients with type 2 diabetes: a randomised clinical trial. Br J Nutr. 2013;110:1601-1610. [PMID: 23551992 DOI: 10.1017/s0007114513001025]

A diet rich in fibre seems to protect against the metabolic syndrome (MetS), but there is scarce information about the role of fibre intake in patients with the MetS and diabetes. The aim of the present study was to evaluate the effects of soluble fibre from partially hydrolysed guar gum (PHGG) on the MetS and cardiovascular risk factors in patients with type 2 diabetes. In the present randomised controlled clinical trial, forty-four patients with type 2 diabetes (males 38·6 %, age 62 (SD 9) years, diabetes duration 14·2 (SD 9·6) years) and the MetS underwent clinical, laboratory and dietary evaluations at baseline, 4 and 6 weeks. All patients followed their usual diet and the intervention group (n 23) received an additional 10 g/d of PHGG. In the intervention group, waist circumference (WC), glycated Hb (HbA1c), 24 h urinary albumin excretion (UAE) and serum trans-fatty acids (FA) were reduced in comparison with baseline after 4 and 6 weeks: WC 103·5 (SD 9·5) to 102·1 (SD 10) to 102·3 (SD 9·7) cm; HbA1c 6·88 (SD 0·99) to 6·64 (SD 0·94) to 6·57 (SD 0·84) %; 24 h UAE 6·8 (interquartile range 3·0-17·5) to 4·5 (interquartile range 3·0-10·5) to 6·2 (interquartile range 3·0-9·5) mg; trans-FA 71 (interquartile range 46-137) to 67 (interquartile range 48-98) to 57 (interquartile range 30-110) mg/l (P< 0·05 for all). The only change in the control group was weight reduction: 77·0 (SD 13·5) to 76·2 (SD 13·3) to 76·1 (SD 13·4) kg (P= 0·005). Other MetS components (blood pressure, TAG, HDL-cholesterol, fasting plasma glucose), total and LDL-cholesterol, C-reactive protein and endothelin-1 did not change in either group. In patients with type 2 diabetes and the MetS, the addition of PHGG to the usual diet improved cardiovascular and metabolic profiles by reducing WC, HbA1c, UAE and trans-FA.

Dietary patterns, calories, and kidney disease

Specific nutritional factors that mediate obesity or CKD remain very difficult to quantify in any population. That being said, several macronutrients, including protein intake, have been examined as risk factors for CKD progression. Given the correlation of micro- and macronutrients within a particular diet and the consistency of an individual's dietary habits over time for most individuals, dietary patterns may have a greater impact on CKD risk and progression. This review focuses on dietary patterns and their association with CKD. To date, studies examining dietary patterns and CKD risk remain very limited, and more studies are needed. However, the follow-up period may need to be fairly long to detect any association. Caloric intake itself may also affect CKD risk. This may be due to the influence of caloric intake on sirtuin1, which modulates adiponectin gene expression and nitric oxide bioavailability.

Long-term high animal protein diet reduces body weight gain and insulin secretion in diet-induced obese rats

BACKGROUND

The effects of a high protein diet on insulin secretion and glucose metabolism have been quite controversial. The aim of this study was to evaluate the effects of long-term isocaloric high animal protein intake on insulin secretion in diet-induced obese rats.

RESULTS

After the experimental period (24 weeks), the high-fat diet-induced obese rats that were fed isocaloric high-protein diets (HP) had lower body weight gain (P < 0.01) and lower visceral fat (P < 0.05) than normal protein (NP) rats. Fasting plasma glucagon-like peptide-1 (GLP-1) was also reduced significantly (P < 0.05), as well as serum insulin levels at 5 min and 10 min by intravenous insulin releasing test. In addition, insulin mRNA and pancreatic duodenal homeodomain-1 (PDX-1), GLP-1 protein expression were both markedly lower in HP rats (P < 0.05), while PDX-1 mRNA in HP rats had no difference from NP rats.

CONCLUSION

These results suggest that long-term isocaloric high animal protein intake reduces the acute insulin response in obese rats and the decrease of insulin is associated with both reduced weight gain and inhibition of PDX-1 expression. GLP-1 might be a negative feedback for the balance of energy metabolism secondary to changes of body weight and visceral fat.

Protein supplementation lowers blood pressure in overweight adults: effect of dietary proteins on blood pressure (PROPRES), a randomized trial

BACKGROUND

Dietary protein intake may help to manage blood pressure (BP) and prevent complications associated with elevated BP.

OBJECTIVE

The objective of this study was to determine whether 4 wk of increased protein intake (∼25% compared with ∼15% of energy intake that isoenergetically replaces carbohydrate intake) lowers office and daytime BP compared with increased carbohydrate intake.

DESIGN

A randomized, double-blind, parallel study compared consumption of 3 × 20 g protein/d (20% pea, 20% soy, 30% egg, and 30% milk-protein isolate) with 3 × 20 g maltodextrin/d. Protein or maltodextrin were isoenergetically substituted for a sugar-sweetened drink. Primary outcomes were office and daytime BP. A total of 99 men and women [age range: 20-70 y; BMI (in kg/m²): 25-35] with untreated elevated BP (BP ≥130/85 and <160/100 mm Hg) were randomly assigned. Ninety-four completers (51 subjects in the maltodextrin group, 43 subjects in the protein group) were included in the analyses.

RESULTS

Office systolic blood pressure (SBP) and diastolic blood pressure (DBP) were 4.9 ± 1.7 mm Hg (P = 0.005) and 2.7 ± 1.3 mm Hg (P = 0.05) lower, respectively, in the protein group. Daytime SBP was 4.6 ± 1.7 mm Hg lower in the protein group (P = 0.006), whereas daytime DBP did not differ between groups (P = 0.37). Urinary sodium excretion was higher in the maltodextrin group (P = 0.004).

CONCLUSION

Increased protein intake, at the expense of maltodextrin, lowers BP in overweight adults with upper-range prehypertension and grade 1 hypertension. This trial was registered at www.trialregister.nl as NTR 1362.