Jaimon T. Kelly

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.

Effectiveness of group-based self-management education for individuals with Type 2 diabetes: a systematic review with meta-analyses and meta-regression.

Patient education for the management of Type 2 diabetes can be delivered in various forms, with the goal of promoting and supporting positive self‐management behaviours. This systematic review aimed to determine the effectiveness of group‐based interventions compared with individual interventions or usual care for improving clinical, lifestyle and psychosocial outcomes in people with Type 2 diabetes.

Beyond Sodium, Phosphate and Potassium: Potential Dietary Interventions in Kidney Disease

People with kidney disease are advised to restrict individual nutrients, such as sodium, potassium, and phosphate, in line with current best practice guidelines. However, there is limited evidence to support the efficacy of single nutrient strategies, and compliance remains a challenge for clinicians to overcome. Many factors contribute to poor compliance with dietary prescriptions, including conflicting priorities for single nutrient restriction, the arduous self‐monitoring required, and the health‐related knock‐on effects resulting from targeting these nutrients in isolation. This paper reviews the evidence base for the overall pattern of eating as a potential tool to deliver a diet intervention in which all the nutrients and foods work cumulatively and synergistically to improve clinical outcomes. These interventions may assist in kidney disease management and overcome these innate challenges that single nutrient interventions possess. Healthy dietary patterns are typically plant‐based and lower in sodium and animal proteins. These patterns may have numerous mechanistic benefits for cardiovascular health in kidney disease, most notably through the increase in fruit, vegetables, and plant‐based protein, as well as improved gut health through the increase in dietary fiber. The evidence to date on optimal dietary patterns points toward use of a predominantly plant‐based diet, and suggests its adoption may improve clinical outcomes in dialysis patients. However, clinical trials are needed to determine whether these diet interventions are feasible, safe, and effective in this patient population.

The Effect of Polyphenol-Rich Interventions on Cardiovascular Risk Factors in Haemodialysis: A Systematic Review and Meta-Analysis

End-stage kidney disease is a strong risk factor for cardiovascular-specific mortality. Polyphenol-rich interventions may attenuate cardiovascular disease risk factors; however, this has not been systematically evaluated in the hemodialysis population. Using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, the following databases were searched: Cochrane Library (http://www.cochranelibrary.com/), MEDLINE (https://health.ebsco.com/products/medline-with-full-text), Embase (https://www.elsevier.com/solutions/embase-biomedical-research), and CINAHL (https://www.ebscohost.com/nursing/products/cinahl-databases/cinahl-complete). Meta-analyses were conducted for measures of lipid profile, inflammation, oxidative stress, and blood pressure. Risk of bias was assessed using the Cochrane Collaboration Risk of Bias tool and quality of the body of evidence was assessed by the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) methodology. Twelve studies were included for review. Polyphenol-rich interventions included soy, cocoa, pomegranate, grape, and turmeric. Polyphenol-rich interventions significantly improved diastolic blood pressure (Mean Difference (MD) −5.62 mmHg (95% Confidence Interval (CI) −8.47, −2.78); I2 = 2%; p = 0.0001), triglyceride levels (MD −26.52 mg/dL (95% CI −47.22, −5.83); I2 = 57%; p = 0.01), and myeloperoxidase (MD −90.10 (95% CI −135.84, −44.36); I2 = 0%; p = 0.0001). Included studies generally had low or unclear risks of bias. The results of this review provide preliminary support for the use of polyphenol-rich interventions for improving cardiovascular risk markers in haemodialysis patients. Due to the limited number of studies for individual polyphenol interventions, further studies are required to provide recommendations regarding individual polyphenol intervention and dose.

Dietary Sources of Protein and Chronic Kidney Disease Progression: The Proof May Be in the Pattern

The medieval philosopher Moses Maimonides (Spain, 1135-1204) wrote that “No disease that can be treated by diet should be treated with any other means.” Not so long ago, before we had the means of dialysis therapy, and still today in many parts of the world, diet represents the sole management strategy in end-stage kidney disease (ESKD).

Effect of resveratrol supplementation on cognitive performance and mood in adults: a systematic literature review and meta-analysis of randomized controlled trials

Context The aim of this systematic review was to evaluate clinical trial data regarding the effect of resveratrol supplementation on cognitive performance and mood in populations that are healthy and in the clinical setting. Data Sources Using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, a systematic literature review of randomized controlled trials was conducted. Data Extraction A meta-analysis was also conducted to determine treatment effect on the following cognitive domains and mental processes: processing speed, number facility, memory, and mood. Risk of bias was assessed using the Cochrane Collaboration Risk of Bias tool. Quality of the body of evidence was assessed by evidence for each outcome related to cognitive function for which data was assessed using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE). Results Ten studies were included. Three studies found resveratrol supplementation significantly improved some measures of cognitive performance, 2 reported mixed findings, and 5 found no effect. When data were pooled, resveratrol supplementation had a significant effect on delayed recognition (standardized mean difference [SMD], 0.39; 95% confidence interval [CI], 0.08-0.70; I2 = 0%; P = 0.01; n = 3 studies; n = 166 participants) and negative mood (SMD, -0.18; 95%CI, -0.31 to -0.05; I2 = 0%; P = 0.006; n = 3 studies; n = 163 participants). Included studies generally had low risk of bias and were of moderate or high quality. Conclusions The results of this review indicate that resveratrol supplementation might improve select measures of cognitive performance; however, the current literature is inconsistent and limited.

Is telehealth effective in managing malnutrition in community-dwelling older adults? A systematic review and meta-analysis

Telehealth offers a feasible method to provide nutrition support to malnourished older adults. This systematic review and meta-analysis aims to determine the efficacy of telehealth methods in delivering malnutrition-related interventions to community-dwelling older adults. Studies in any language were searched in five electronic databases from inception to 2nd November 2017. Quality of the evidence was assessed using the Cochrane Risk of Bias tool and the GRADE approach. Nine studies were identified, with results published across 13 included publications, which had mostly low to unclear risk of bias. There were two interventions delivered to disease-specific groups, one with kidney disease and one with cancer; the remaining seven interventions were delivered to patients with mixed morbidities following discharge from an inpatient facility. Seven studies delivered telehealth via telephone consultations and two used internet-enabled telemedicine devices. Ten meta-analyses were performed. Malnutrition-focused telehealth interventions were found to improve protein intake in older adults by 0.13 g/kg body weight per day ([95%CI: 0.01-0.25]; P = .03; n = 2 studies; n = 200 participants; I2 = 41%; GRADE level: low) and to improve quality of life (standardised mean difference: 0.55 [95%CI: 0.11-0.99]; P = .01; n = 4 studies with n = 9 quality-of-life tools; n = 248 participants; I2 = 84%: GRADE level: very low). There were also trends towards improved nutrition status, physical function, energy intake, hospital readmission rates and mortality in the intervention groups. Overall, this review found telehealth is an effective method to deliver malnutrition-related interventions to older adults living at home, and is likely to result in clinical improvements compared with usual care or no intervention. However, further research with larger samples and stronger study designs are required to strengthen the body of evidence.

The effect of dietary sodium modification on blood pressure in studies of subjects with systolic blood pressure less than 140mmHg: a systematic review protocol

Review question/objective The objective of this review is to establish the effect of modifying dietary sodium intake in normotensive subjects. More specifically, the objectives are to identify the effect of reducing or increasing sodium intake on blood pressure in normotensive subjects with systolic blood pressure (SBP) <140mmHg, and the effect of sodium reduction or supplementation on arterial function in subjects with baseline SBP <140mmHg. Background The pressure‐natriuresis relationship that was first described by Guyton1 proposes a link between dietary sodium intake and renal sodium handling. Specifically, the hypothesis states that in a normal individual, consumption of a dietary sodium load will elicit a transient rise in blood pressure that stimulates the kidney to excrete sodium. The kidney will excrete excess sodium leading to restoration of normal blood pressure. This hypothesis explains how blood pressure is maintained over the longer term even though most individuals report day‐to‐day variation in sodium intake.1,2 Following this hypothesis, intervention studies in normotensive subjects may be expected to observe a small amount of variation in blood pressure with changes to dietary sodium intake, but this variation should be small enough to be considered clinically irrelevant. Intervention studies examining the effect of dietary sodium have reported a range of different responses from significant changes,3,4 to mild, to moderate effects on blood pressure to no effect at all.5,6 Normotensive studies that report blood pressure changes over the long‐term have previously documented changes in systolic blood pressure (SBP) ranging from ‐1mmHg7 to increases of 8.2mmHg.4 Previous systematic reviews of blood pressure response to dietary sodium restriction have used Cochrane Collaboration methods.8‐10 One such systematic review9 has been cited over 370 times, and has been used in the development of dietary guidelines.11 Two of these reviews attempted to conduct meta‐analysis by dividing subjects into normotensive and hypertensive sub‐groups.8,9 Both reviews failed to specify methods for determining whether studies recruited hypertensive or normotensive subjects and included some studies in the normotensive analyses with subjects who had baseline blood pressures above 140mmHg. Due to this, a wide range of baseline blood pressure readings and responses can be observed in normotensive analyses, which is inconsistent with Guytons pressure natriuresis hypothesis. Therefore, the validity of the findings for blood pressure changes in healthy normotensive individuals in these analyses is limited in that the majority of the included studies recruited subjects with SBP above 140mmHg.4,12‐16 Subjects with hypertension (SBP >140mmHg) have been shown to respond differently to dietary sodium and hence inclusion of these studies in previous normotensive analyses may have skewed the results.9 These analyses in “normotensive” populations could be improved if studies that recruited subjects with SBP >140mmHg were excluded. As well as examining blood pressure, a number of intervention studies have investigated the effects of dietary sodium intake on arterial function and found that these effects may be, at least partly, independent of blood pressure.17,18 As these effects may be key in extending our understanding of sodium intake and disease risk, they form part of the bigger picture for dietary sodium intake and chronic disease risk. It is therefore important to consider data on arterial function such as pulse wave analysis, pulse wave velocity, and flow mediated dilation in future meta‐analyses of sodium restriction. There is enough evidence from normotensive studies conducted in subjects with SBP≤140mmHg to conduct a separate investigation of the effects on blood pressure and arterial function. This systematic review will consider the evidence for long‐term dietary sodium restriction in subjects with SBP <140mmHg on arterial function.

Dietetics workforce preparation and preparedness in Australia: A systematic mapping review to inform future dietetics education research: Dietetics workforce preparation: a review

AIM The present study aimed to systematically map and summarise existing research regarding dietetics workforce preparation and preparedness that has been conducted in Australia. The secondary aim was to then identify gaps in the literature to inform future priority areas in Australian dietetics education research. METHODS The databases MEDLINE, CINAHL, Embase, ERIC, Informit and PsycINFO were systematically searched from inception until July 2017 using key search terms to identify eligible studies. Extracted data were independently reviewed, and study quality was appraised by multiple researchers. Results were categorised by setting and primary focus/foci and then narratively summarised. RESULTS Sixty-eight studies were included from 3779 records identified. Dietetics education research in Australia has spanned almost 30 years with more than half of studies (51%; 35/68) published in the last five years. The greatest proportion of research was conducted in the university setting (43%; 29/68), with students as participants (48%; 43/90) and was focused on the medical nutrition therapy area of dietetics practice (43%; 29/68). Published studies involving graduates (14%; 13/90); conducted in the workplace (12%; 8/68); and regarding emerging areas of dietetics practice (0%; 0/90) are lacking. Employment outcomes of dietetics graduates across Australia were last published over 25 years ago. CONCLUSIONS This review provides a map for dietetics educators and researchers in Australia to guide future research regarding the preparation and preparedness of dietitians. Advancing the Australian dietetics workforce of the future will require a strategic, coordinated and collaborative approach to address the research gaps identified in this review.

Primary Versus Secondary Prevention of Chronic Kidney Disease: The Case of Dietary Protein

The proclamation that “the greatest medicine of all is to teach people how not to need it” (Hippocrates. 460-370 BC, Greece) is the basic principle of primary disease prevention, which aims to prevent disease before it ever occurs. Preventing exposures to hazards that cause disease, such as altering unhealthy behaviors, is one example of primary disease prevention. Secondary or tertiary disease prevention, however, refers to reducing the impact of a disease that has already occurred, or limiting the impact of an ongoing illness that has lasting effects, respectively. Salutary diets or lifestyles for primary versus secondary/tertiary disease prevention may not necessarily align.