Diet quality, Self-efficacy and Health Literacy in Adults with Chronic Kidney Disease: A Cross-Sectional Study.

OBJECTIVE: Adherence to high quality dietary patterns is associated with lower risk of disease progression and all-cause mortality in chronic kidney disease (CKD). Self-efficacy and health literacy are recognised as factors that may lead to better adherence to high quality diets. However, these associations are not well studied in CKD. This study aims to explore the relationship between health literacy, self-efficacy, and diet quality in CKD. METHODS: Participants with CKD stages 3a-5 recruited from three large tertiary hospitals were assessed using the Self-Efficacy for Managing Chronic Disease 6-item scale (SEMCD-6), the Health Literacy Questionnaire (HLQ) and the Australian Eating Survey (AES) Food Frequency Questionnaire. Diet quality was measured using the Australian Recommended Food Score (ARFS). Associations were examined using multivariable linear regression models, adjusted for sex and type 2 diabetes (T2D) diagnosis. RESULTS: Sixty participants were included in the analysis. Mean age of participants was 74.5 years old and 58% were male. The mean ARFS was poor (Mean=29.9±9.1/73) and characterised by high intake of processed foods and animal protein, and low intake of fruit and vegetables. Mean SEMCD-6 was high (7.12±2.07/10). Self-efficacy and health literacy domains 6 - Actively engage with healthcare providers and 7 - Navigating healthcare system independently predicted diet quality in the adjusted model for sex and T2D. CONCLUSION: Adults with CKD report suboptimal diet quality. The results suggest that self-efficacy and aspects of health literacy should be considered when designing interventions aimed at improving diet quality in people with CKD.

Effectiveness of diet quality indices in measuring a change in diet quality over time: a systematic review and meta-analysis of randomized controlled trials.

CONTEXT: Diet quality indices (DQIs) were developed to score and rank adherence to dietary patterns in observational studies, but their use to measure changes in diet quality in intervention trials is becoming common in the literature. OBJECTIVE: This systematic review and meta-analysis aimed to assess the effectiveness of DQIs to measure change in diet quality in intervention trials. DATA SOURCES: MEDLINE, CINAHL, Embase, and the Cochrane Central Register of Controlled Trials databases were searched from January 1994 to June 2020. Two reviewers independently completed full-text screening. Eligible studies were randomized controlled trials that used validated a priori DQIs to measure change in diet quality in adults. DATA EXTRACTION: Data were extracted by an independent reviewer and reviewed by the research team. Risk of bias was assessed by the Cochrane Collaboration's Risk of Bias 2.0 tool. DATA ANALYSIS: The 34 included studies (52% of reviewed studies, 0.6% of initially identified studies) used 10 different DQIs, 7 of which were able to measure significant change in diet quality. Meta-analyses of pooled results demonstrated change in the Healthy Eating Index (MD 5.35; 95%CI, 2.74-7.97; P < 0.001) and the Mediterranean Dietary Adherence Screener (MD 1.61; 95%CI, 1.00-2.23; P < 0.001) scores. DQIs were more likely to measure change in diet quality if they reflected the diet pattern being implemented, if the intervention was significantly different from the baseline and control diets, and if the study was adequately powered to detect change. CONCLUSION: DQIs are responsive to change in diet quality in intervention trials when the index used reflects the dietary changes made and the study is adequately powered. The appropriate selection of a DQI to suitably match dietary changes and study populations is important for future dietary intervention trials. SYSTEMATIC REVIEW REGISTRATION: PROSPERO registration no. CRD42020181357.

Re-Thinking Hyperkalaemia Management in Chronic Kidney Disease-Beyond Food Tables and Nutrition Myths: An Evidence-Based Practice Review.

Potassium dysregulation can be life-threatening. Dietary potassium modification is a management strategy for hyperkalaemia. However, a 2017 review for clinical guidelines found no trials evaluating dietary restriction for managing hyperkalaemia in chronic kidney disease (CKD). Evidence regarding dietary hyperkalaemia management was reviewed and practice recommendations disseminated. A literature search using terms for potassium, hyperkalaemia, and CKD was undertaken from 2018 to October 2022. Researchers extracted data, discussed findings, and formulated practice recommendations. A consumer resource, a clinician education webinar, and workplace education sessions were developed. Eighteen studies were included. Observational studies found no association between dietary and serum potassium in CKD populations. In two studies, 40-60 mmol increases in dietary/supplemental potassium increased serum potassium by 0.2-0.4 mmol/L. No studies examined lowering dietary potassium as a therapeutic treatment for hyperkalaemia. Healthy dietary patterns were associated with improved outcomes and may predict lower serum potassium, as dietary co-factors may support potassium shifts intracellularly, and increase excretion through the bowel. The resource recommended limiting potassium additives, large servings of meat and milk, and including high-fibre foods: wholegrains, fruits, and vegetables. In seven months, the resource received > 3300 views and the webinar > 290 views. This review highlights the need for prompt review of consumer resources, hospital diets, and health professionals' knowledge.

Quality and validity of diet quality indices for use in Australian contexts: a systematic review.

Diet quality indices (DQIs) are tools used to evaluate the overall diet quality against dietary guidelines or known healthy dietary patterns. This review aimed to evaluate DQIs and their validation processes to facilitate decision making in the selection of appropriate DQI for use in Australian contexts. A search of CINAHL, PubMed and Scopus electronic databases was conducted for studies published between January 2010 and May 2020, which validated a DQI, measuring > 1 dimension of diet quality (adequacy, balance, moderation, variety) and was applicable to the Australian context. Data on constructs, scoring, weighting and validation methods (construct validity, criterion validity, reliability and reproducibility) were extracted and summarised. The quality of the validation process was evaluated using COnsensus-based Standards for the selection of health Measurement INstruments Risk of Bias and Joanna Briggs Appraisal checklists. The review identified twenty-seven indices measuring adherence to: national dietary guidelines (n 13), Mediterranean Diet (n 8) and specific population recommendations and chronic disease risk (n 6). Extensiveness of the validation process varied widely across and within categories. Construct validity was the most strongly assessed measurement property, while evaluation of measurement error was frequently inadequate. DQIs should capture multiple dimensions of diet quality, possess a reliable scoring system and demonstrate adequate evidence in their validation framework to support use in the intended context. Researchers need to understand the limitations of newly developed DQIs and interpret results in view of the validation evidence. Future research on DQIs is indicated to improve evaluation of measurement error, reproducibility and reliability.