Calcium isotopes as a biomarker for vascular calcification in chronic kidney disease.

Calcium balance is abnormal in adults with chronic kidney disease (CKD) and is associated with the development of vascular calcification. It is currently not routine to screen for vascular calcification in CKD patients. In this cross-sectional study, we investigate whether the ratio of naturally occurring calcium (Ca) isotopes, 44Ca and 42Ca, in serum could be used as a noninvasive marker of vascular calcification in CKD. We recruited 78 participants from a tertiary hospital renal center: 28 controls, 9 subjects with mild-moderate CKD, 22 undertaking dialysis and 19 who received a kidney transplant. For each participant, systolic blood pressure, ankle brachial index, pulse wave velocity, and estimated glomerular filtration rate were measured, along with serum markers. Calcium concentrations and isotope ratios were measured in urine and serum. While we found no significant association between urine Ca isotope composition (noted δ44/42Ca) between the different groups, δ44/42Ca values in serum were significantly different between healthy controls, subjects with mild-moderate CKD and those undertaking dialysis (P < 0.01). Receiver operative characteristic curve analysis shows that the diagnostic utility of serum δ44/42Ca for detecting medial artery calcification is very good (AUC = 0.818, sensitivity 81.8% and specificity 77.3%, P < 0.01), and performs better than existing biomarkers. Although our results will need to be verified in prospective studies across different institutions, serum δ44/42Ca has the potential to be used as an early screening test for vascular calcification.

Acute kidney injury increases risk of kidney stones-a retrospective propensity score matched cohort study.

BACKGROUND: Acute kidney injury (AKI) is common. An episode of AKI may modify the risk of developing kidney stones by potential long-term effects on urine composition. We aimed to investigate the association between AKI and the risk of kidney stone presentations. METHODS: The retrospective cohort study used patient data (1 January 2008-31 December 2017), from an Australian Local Health District, which included AKI diagnosis, demographics, comorbidities and kidney stone admissions. Time-varying Cox proportional hazards and propensity-matched analysis were used to determine the impact of AKI on the risk of kidney stones. To address possible population inhomogeneity in comparisons between no AKI and hospitalized AKI, sub-group analysis was done comparing inpatient and outpatient AKI versus no AKI, to assess consistency of association with future stones. Sensitivity analysis was undertaken to capture the impact of a known AKI status and AKI severity. RESULTS: Out of 137 635 patients, 23 001 (17%) had an AKI diagnosis and 2295 (2%) had kidney stone presentations. In the unadjusted analysis, AKI was associated with kidney stones, with AKI used as a time-varying exposure, [hazard ratio (HR) 1.32, 95% confidence interval (CI) 1.16-1.50)]. Both inpatient-AKI (HR 1.19, 95% CI 1.01-1.39) and outpatient-AKI (HR 1.59, 95% CI 1.30-1.94) were significantly associated with future stones compared to no AKI subjects. This association persisted in the adjusted analysis (HR 1.45, 95% CI 1.26-1.66), propensity-matched dataset (HR 1.67, 95% CI 1.40-1.99) and sensitivity analysis. There was a dose-response relationship with higher stages of AKI being associated with a greater risk of kidney stones. CONCLUSIONS: In a large cohort of patients, AKI is associated with a greater risk of kidney stones, which increases with higher stages of AKI. This association should be examined in other cohorts and populations for verification.

Association of Peritonitis With Cardiovascular Mortality Over Time in the Peritoneal Dialysis Population: An Australia and New Zealand Dialysis and Transplant Registry Study.

Introduction: Though peritonitis is associated with increased mortality in patients receiving peritoneal dialysis (PD), its association with cardiovascular mortality remains uncertain. Methods: The study participants included adult patients (≥18 years old) commencing PD in Australia (from October 2003 to December 2019) using the Australia and New Zealand Dialysis and Transplant (ANZDATA) registry. Association between peritonitis and cardiovascular mortality was evaluated using Cox proportional hazards analysis and competing risks analysis. Associations between peritonitis rates between different eras and cardiovascular mortality were also compared using Jointpoint regression model to determine the time point when a significant change in peritonitis trend occurred to define the era for cardiovascular mortality. Subgroup analysis dividing the groups into 0, 1 and ≥2 episodes of peritonitis and sensitivity analysis censoring at 90 days post-transfer to hemodialysis (HD) were performed. Results: The study included 9699 incident PD patients. The overall peritonitis rate was 0.37 episodes per patient-year and declined by 4.7% (95% confidence interval [CI] 3.6-5.8%) during the study period. Peritonitis was associated with increased cardiovascular mortality risk (subdistribution hazard ratio [SHR] 1.53, 95% CI 1.39-1.69, P < 0.001) with increasing peritonitis episodes associated with higher risk (1 episode of peritonitis SHR 1.41, 95%CI 1.24-1.61; ≥2 episodes of peritonitis SHR 1.69, 95% CI 1.47-1.93, P < 0.001). Patients who commenced PD between 2012 and 2019 had a lower risk of cardiovascular mortality (SHR 0.60, 95% CI 0.50-0.72, P < 0.001), compared to patients who commenced between 2003 and 2011. Results were consistent in the sensitivity analysis. Conclusion: Peritonitis is independently associated with an increased risk of cardiovascular mortality, and the association is episode-dependent. Prevention and adequate treatment of PD peritonitis may improve cardiovascular outcomes among patients receiving PD.

Exploring the Agreement Between Self-Reported Medication Adherence and Pharmacy Refill-Based Measures in Patients with Kidney Disease.

Aim: To assess the quantitative and categorical agreement between two methods of measuring medication adherence: pharmacy refill-based medication possession rates and self-reported medication adherence scale. Background: Categorisation of adherence metrics using empirical cut-off scores can lead to misclassification, which can be overcome by expressing adherence as a continuous variable. Pharmacy refill-based adherence can be reported as actual rates, but the validity of expressing self-reported medication adherence scores as a continuous variable to reflect adherence is unknown and its quantitative agreement with refill-based adherence rates untested. Methods: Patients with kidney disease, including dialysis patients, from Illawarra Shoalhaven region of New South Wales, Australia were recruited between January 2015 and June 2016 to this cross-sectional study. Medication adherence was assessed using the self-reported Morisky Medication Adherence Scale (MMAS) and two pharmacy refill-based measures, Medication Possession Ratio (MPR) and Proportion of Days Covered (PDC) for antihypertensives and cardiometabolic drugs. Categorical and quantitative agreement between self-reported adherence and pharmacy refill-based adherence were assessed using tests of trend, analysis of covariance (ANCOVA), Cohen's kappa and Bland-Altman analysis. Results: We recruited 113 patients. There was a significant declining trend of MPR (p < 0.001) and PDC (<0.001 for antihypertensives, p = 0.004 for cardiometabolic) scores among categories with worsening MMAS adherence. Adjusted ANCOVA showed significant association between self-report and pharmacy refill-based adherence (p < 0.001). Weighted Cohen's kappa statistics showed fair agreement between the self-report and pharmacy refill-based categories. Bland-Altman's analysis showed less than 5% of cases were outside the limits of agreement (-0.36 to 0.27) and the bias for MMAS was negative (-0.05 to -0.09), indicating MMAS did not overestimate adherence. Conclusion: There is modest agreement between pharmacy refill-based measures and self-report MMAS measures when assessed categorically or quantitatively. Assessing adherence as a continuous variable should be considered to overcome the challenges associated with categorization of adherence based on arbitrary thresholds.

Retrospective study on the epidemiology of antineutrophil cytoplasmic autoantibodies-associated vasculitis in two Australian health districts.

BACKGROUND: Antineutrophil cytoplasmic autoantibodies (ANCA)-associated vasculitis (AAV) is more prevalent in rural Australia compared with metropolitan areas, suggesting a role of environment in disease pathogenesis. However, the prevalence of environmental risk factors in Australian AAV patients has not been described. AIMS: To compare the incidence of AAV between two health districts (Illawarra Shoalhaven Local Health District (ISLHD), a mixed rural/metropolitan region, and South Eastern Sydney Local Health District (SESLHD), a metropolitan region) in Australia and its relationship to environmental exposures. METHODS: Cases of AAV from 2002 to 2017 were retrospectively identified from ISLHD and SESLHD using electronic medical records. Eligible participants were invited to complete a standardised questionnaire examining their exposure to silica, solvents, metal, dust, farming, gardening and sunlight. RESULTS: One hundred and fifty-six cases of AAV were identified from 2002 to 2017. A higher cumulative incidence of AAV was observed in the ISLHD (184.2 (95% confidence interval (CI) 143.6-232.7) per million) compared with SESLHD (102.6 (95% CI 82.1-126.8) per million). Over 50% of the cohort had high levels of silica and solvents exposure, based on self-reported questionnaires. There was no significant relationship between region and exposure to silica (P = 0.96), solvents (P = 0.44), metal (P = 0.33), dust (P = 0.25), farming (P = 0.90), gardening (P = 0.93) or sunlight (P = 0.55). CONCLUSIONS: We found a higher incidence of AAV in ISLHD compared with SESLHD with high levels of exposure to silica and solvents in both regions based on self-reported questionnaires. Prospective systematic collection of data, such as a registry of AAV, is warranted to further explore the relationship between environmental exposures and AAV.

Prescribed Water Intake in Autosomal Dominant Polycystic Kidney Disease.

BACKGROUND: Arginine vasopressin promotes kidney cyst growth in autosomal dominant polycystic kidney disease (ADPKD). Increased water intake reduces arginine vasopressin and urine osmolality and may slow kidney cyst growth. METHODS: In this randomized controlled 3-year clinical trial, we randomly assigned adults with ADPKD who had a height-corrected total kidney volume in Mayo imaging subclass categories 1B to 1E and an estimated glomerular filtration rate of 30 ml/min/1.73 m2 or greater to (1) water intake prescribed to reduce 24-hour urine osmolality to 270 mOsmol/kg or less or (2) ad libitum water intake irrespective of 24-hour urine osmolality. The primary end point was the percentage annualized rate of change in height-corrected total kidney volume. RESULTS: A total of 184 patients participated in either the ad libitum water intake group (n=92) or the prescribed water intake group (n=92). Over 3 years, there was no difference in the annualized rate of change in height-corrected total kidney volume between the ad libitum (7.8% per year; 95% confidence interval [CI], 6.6 to 9.0) and prescribed (6.8% per year; 95% CI, 5.8 to 7.7) water intake groups (mean difference, −0.97% per year; 95% CI, −2.37 to 0.44; P=0.18). The difference in mean 24-hour urine osmolality between the ad libitum and prescribed water intake groups was −91 mOsmol/kg (95% CI, −127 to −54 mOsmol/kg), with 52.3% of patients achieving adherence to the target 24-hour urine osmolality and no reduction in serum copeptin over 3 years. The frequency of adverse events was similar between groups. CONCLUSIONS: For patients with ADPKD, prescribed water intake was not associated with excess adverse events and achieved the target 24-hour urine osmolality for half of the patients but did not reduce copeptin or slow the growth of total kidney volume over 3 years compared with ad libitum water intake. (Funded by the National Health and Medical Research Council of Australia [grant GNT1138533], Danone Research, PKD Australia, the University of Sydney, and the Westmead Medical Research Foundation; Australian New Zealand Clinical Trials Registry number, ACTRN12614001216606).

Changes in measures of cognitive function in patients with end-stage kidney disease on dialysis and the effect of dialysis vintage: A longitudinal cohort study.

INTRODUCTION: Prevalence of cognitive impairment increases with worsening severity of chronic kidney disease (CKD) and majority of end-stage kidney disease (ESKD) patients on dialysis have cognitive impairment. Trends of cognitive function (CF) in this population are less well known with published studies reporting conflicting results. METHODS: We assessed CF in a cohort of non-dialysis CKD and ESKD patients undergoing dialysis using modified mini-mental state examination (3MS), trail-making test (TMT-A & B) scores and Stroop task, and evaluated demographics, comorbidities and depression using Beck depression inventory at baseline. We repeated tests of CF and depression ≥ 1-year after baseline in both groups and compared change scores in CF and depression between ESKD/ CKD sub-groups. Among ESKD patients we compared change scores between patients with dialysis vintage of <1-year and >1-year. Analysis of covariance was used to adjust for the effect of age on these change scores. RESULTS: At baseline (N = 211), compared to CKD (N = 108), ESKD (N = 103) patients had significantly worse CF based on 3MS and TMT-A & B scores, and depression scores. On follow-up (N = 160) 3MS scores, especially the memory subscale significantly improved in ESKD, but worsened in CKD, with no significant changes in TMT A /TMT-B, or depression scores after adjusting for age. Among ESKD patients, 3MS, especially memory subscale improved in patients with dialysis vintage <1-year compared to >1-year. The 51 patients who discontinued after baseline assessment had worse baseline CF scores suggesting differential attrition. CONCLUSION: Though baseline cognitive scores were worse in ESKD patients on dialysis, compared to CKD, their 3MS, especially memory subscale improved on follow-up. Among ESKD patients, the improvement was significant only in patients who have been on dialysis for less than one-year which may indicate a beneficial effect of clearance of uraemic toxins. Differential attrition of study subjects may have impacted the observed results.

Peritoneal dialysis-related peritonitis as a risk factor for cardiovascular events.

BACKGROUND: Cardiovascular disease is the leading cause of mortality in peritoneal dialysis (PD) patients. Infection is known to increase the risk of cardiovascular events (CVE); however, no studies have examined the association between PD peritonitis and CVE. AIM: To examine peritonitis as a risk factor for CVE in PD patients. METHODS: This retrospective cohort study included all adults undertaking PD for ≥3 months in one Australian health district from 2001 to 2015. Baseline characteristics and peritonitis event information was obtained from the Australian and New Zealand Dialysis and Transplant registry. The Centre for Health Research Illawarra Shoalhaven Population facilitated data linkage using ICD10 coding to capture CVE information. RESULTS: A total of 211 patients was included, with median age of 66 years (interquartile range 54.49-74.45); 64% were male. Peritonitis occurred in 114 (54%) patients and 65 (30.8%) patients experienced a CVE. Identified risk factors for CVE included: cerebrovascular disease (hazard ratio (HR) 2.72, 95% confidence interval (CI) 1.36-5.47), diabetes (HR 2.41, 95% CI 1.47-3.96), coronary artery disease (HR 1.67, 95% CI 1.01-2.77) and age (HR 1.03, 95% CI 1.01-1.06). There was no significant increase in risk of CVE following peritonitis (HR 1.37, 95% CI 0.81-2.32, P = 0.24), even when accounting for age, cerebrovascular disease, diabetes and existing coronary artery disease (HR 1.32, 95% CI 0.78-2.23, P = 0.30). CONCLUSIONS: We did not find an increase in the risk of CVE following a peritonitis episode in PD patients. This result may be due to small sample size or rapid peritonitis treatment mitigating cardiovascular risk.

Assessment of Dietary Sodium Intake Using the Scored Salt Questionnaire in Autosomal Dominant Polycystic Kidney Disease.

The excess intake of dietary sodium is a key modifiable factor for reducing disease progression in autosomal dominant polycystic kidney disease (ADPKD). The aim of this study was to test the hypothesis that the scored salt questionnaire (SSQ; a frequency questionnaire of nine sodium-rich food types) is a valid instrument to identify high dietary salt intake in ADPKD. The performance of the SSQ was evaluated in adults with ADPKD with an estimated glomerular filtration rate (eGFR) ≥ 30 mL/min/1.73 m2 during the screening visit of the PREVENT-ADPKD trial. High dietary sodium intake (HSI) was defined by a mean 24-h urinary sodium excretion ≥ 100 mmol/day from two collections. The median 24-h urine sodium excretion was 132 mmol/day (IQR: 112-172 mmol/d) (n = 75; mean age: 44.6 ± 11.5 years old; 53% female), and HSI (86.7% of total) was associated with male gender and higher BMI and systolic blood pressure (p < 0.05). The SSQ score (73 ± 23; mean ± SD) was weakly correlated with log10 24-h urine sodium excretion (r = 0.29, p = 0.01). Receiving operating characteristic analysis showed that the optimal cut-off point in predicting HSI was an SSQ score of 74 (area under the curve 0.79; sensitivity 61.5%; specificity 90.0%; p < 0.01). The evaluation of the SSQ in participants with a BMI ≥ 25 (n = 46) improved the sensitivity (100%) and the specificity (100%). Consumers with an SSQ score ≥ 74 (n = 41) had higher relative percentage intake of processed meats/seafood and flavourings added to cooking (p < 0.05). In conclusion, the SSQ is a valid tool for identifying high dietary salt intake in ADPKD but its value proposition (over 24-h urinary sodium measurement) is that it may provide consumers and their healthcare providers with insight into the potential origin of sodium-rich food sources.

Breaking the adherence barriers: Strategies to improve treatment adherence in dialysis patients.

Nonadherence to therapy (dietary/fluid restrictions, medications, and dialysis treatment), is common in patients with end-stage kidney disease (ESKD) undergoing dialysis. It is associated with a higher risk of mortality and adverse outcomes. Clinical trials evaluating adherence improvement interventions have largely addressed patient-related factors by employing educational/cognitive, counselling/behavioral, psychological strategies, or combinations thereof. A major barrier to progress in addressing ESKD-related adherence is the difficulty in comparing these trials due to the highly diverse nature of interventions and adherence outcomes. Surrogate outcomes like changes in inter-dialysis weight gain or phosphate levels are frequently used without adjusting for confounders, with the potential for biased efficacy estimates. A majority of trials reported improvement in some adherence measures, but some of the same studies showed no improvement in other adherence markers, questioning the validity of outcome measurement. Among the interventions, cognitive/behavioral strategies, combination strategies, and individually delivered interventions may have some advantages. Relapse of nonadherence, which is common on follow-up, should be managed to sustain long-term adherence. Technology-based interventions hold great future potential for addressing ESKD nonadherence. Streamlining intervention strategies and standardizing outcome measures in future clinical trials will provide reliable guidance to manage nonadherence effectively, which may improve clinical outcomes in dialysis patients.

Comparison of health literacy profile of patients with end-stage kidney disease on dialysis versus non-dialysis chronic kidney disease and the influencing factors: a cross-sectional study.

OBJECTIVES: Lower health literacy (HL) is associated with poor outcomes in patients with kidney disease. Since HL matches the patient's competencies with the complexities of the care package, the level of HL sufficient in earlier stages of chronic kidney disease (CKD) may be inadequate for patients with end-stage kidney disease (ESKD) on dialysis. We aimed to analyse the HL profile of patients with ESKD and non-dialysis CKD and examine if there were significant associations with covariates which could be targeted to address HL deficits, thereby improving patient outcomes. DESIGN AND SETTING: Cross-sectional study of patients with CKD and ESKD from a single Australian health district. METHODS: We assessed the HL profile of 114 patients with CKD and 109 patients with ESKD using a 44-item multidomain Health Literacy Questionnaire (HLQ) and examined its association with demographic factors (age, gender, race), smoking, income, education, comorbidities, carer status, cognitive function and depression. Using multivariable logistic regression models, HL profiles of patients with CKD and ESKD were evaluated after adjusting for covariates. RESULTS: Patients with ESKD had similar demographics and educational levels compared with patients with CKD. ESKD had significantly higher frequency of vascular disease, cognitive impairment and depression. Patients with ESKD had better HL scores for the social support domain (37.1% vs 19.5% in higher HLQ4 tertile, p=0.004), whereas all other HL domains including engagement with healthcare providers were comparable to CKD. Depression was independently associated with nearly all of the HL domains (HLQ1: OR 2.6, p=0.030; HLQ2: OR 7.9, p=<0.001; HLQ3: OR 7.6, p<0.001; HLQ4: OR 3.5, p=0.010; HLQ5: OR 8.9, p=0.001; HLQ6: OR 3.9, p=0.002; HLQ7: OR 4.8, p=0.001; HLQ8: OR 5.3, p=0.001) and education with HL domains relevant to processing health-related information (HLQ8: OR 2.6, p=0.008; HLQ9: OR 2.5, p=0.006). CONCLUSIONS: Despite very frequent interactions with health systems, patients with ESKD on dialysis did not have higher HL in engagement with health providers and most other HL domains, compared with patients with CKD. Strategies promoting patient-provider engagement and managing depression which strongly associates with lower HL may address the impact of HL deficits and favourably modify clinical outcomes in renal patients.

Safety and Efficacy of Using Nuts to Improve Bowel Health in Hemodialysis Patients.

OBJECTIVE: Constipation is common in patients with end-stage kidney disease. Nondrug strategies to manage constipation are challenging because of dietary potassium, phosphate, and fluid restrictions. Nuts are a high-fiber food but are excluded from the diet because of the high potassium and phosphate content. The aim of this study was to examine the safety and efficacy of using nuts to improve constipation in adults undertaking hemodialysis (HD). DESIGN AND METHODS: Adult patients undertaking HD were recruited to this nonrandomized, 10-week repeated measures, within-subject, pragmatic clinical trial, conducted in two HD units. The intervention consisted of consumption of 40g of raw almonds daily for four weeks, followed by a two-week washout and four-week control period. The primary safety outcome measures were change in predialysis serum potassium and phosphate levels. The primary efficacy outcome was reduction in constipation, measured using the Bristol Stool Form Scale and Palliative Care Outcome Scale (POS-S) renal symptom score. Secondary outcomes included quality of life, selected uremic toxins, cognition, gut microbiota profile, and symptom burden. RESULTS: Twenty patients completed the trial (median age: 67 [interquartile range: 57.5-77.8] years, 51% male). After controlling for dialysis adequacy, anuria, dietary intake, bicarbonate, and parathyroid hormone, there were no statistically significant changes in serum potassium (P = 0.21) or phosphate (P = 0.16) associated with daily consumption of almonds. However, statistically significant improvements in constipation were seen at weeks 2, 3, 4, and 10. There were statistically significant improvements in quality of life (P = 0.030), overall symptom burden (P = 0.002), vomiting (P = 0.020), itching (P = 0.006), and skin changes (P = 0.002). CONCLUSION: Daily consumption of almonds for four weeks was safe, effective, and well tolerated. Improvements in quality of life and symptom burden warrant further research to elucidate potential mechanisms. The findings support the potential reinclusion of foods such as nuts into the diet of patients who underwent HD.

Strategies to improve dietary, fluid, dialysis or medication adherence in patients with end stage kidney disease on dialysis: A systematic review and meta-analysis of randomized intervention trials.

BACKGROUND: In patients with end stage kidney disease (ESKD) on dialysis, treatment non-adherence is common and results in poor health outcomes. However, the clinical benefits of interventions to improve adherence in dialysis patients are difficult to evaluate since trialled interventions and reported outcomes are highly diverse/ heterogeneous. This review summarizes existing literature on randomized controlled trials (RCTs) evaluating adherence interventions in ESKD patients focusing on the intervention category, outcome efficacy and persistence of benefit beyond the intervention. METHODS: We performed electronic database searches in Medline, Embase & Cochrane CENTRAL upto 1st July 2018 for RCTs evaluating interventions to improve diet, fluid, medication or dialysis adherence in ESKD patients. Study characteristics including category of interventions, outcomes, efficacy and follow-up were assessed. Meta-analysis was used to compute pooled estimates of the effects on the commonest reported outcome measures. RESULTS: From 1311 citations, we included 36 RCTs (13 cluster-randomized trials), recruiting a total of 3510 dialysis patients (mean age 55.1 ± 5.8 years, males 58.1%). Overall risk of bias was 'high' for 24 and of 'some concern' for 12 studies. Most interventions (33 trials, 92%) addressed patient related factors, and included educational/cognitive (N = 11), behavioural / counselling (N = 4), psychological/affective (N = 4) interventions or a combination (N = 14) of the above. A majority of (28/36) RCTs showed improvement in some reported outcomes. Surrogate measures like changes in phosphate (N = 19) and inter-dialytic weight gain (N = 15) were the most common reported outcomes and both showed significant improvement in the meta-analysis. Sixteen trials reported follow-up (1-12 months) beyond intervention and the benefits waned or were absent in nine trials within 12 months post-intervention. CONCLUSIONS: Interventions to improve treatment adherence result in modest short-term benefits in surrogate outcome measures in dialysis patients, but significant improvements in trial design and outcome reporting are warranted to identify strategies that would achieve meaningful and sustainable clinical benefits. LIMITATIONS: Poor methodological quality of trials. Frequent use of surrogate outcomes measures. Low certainly of evidence.

Randomised controlled trial to determine the efficacy and safety of prescribed water intake to prevent kidney failure due to autosomal dominant polycystic kidney disease (PREVENT-ADPKD).

INTRODUCTION: Maintaining fluid intake sufficient to reduce arginine vasopressin (AVP) secretion has been hypothesised to slow kidney cyst growth in autosomal dominant polycystic kidney disease (ADPKD). However, evidence to support this as a clinical practice recommendation is of poor quality. The aim of the present study is to determine the long-term efficacy and safety of prescribed water intake to prevent the progression of height-adjusted total kidney volume (ht-TKV) in patients with chronic kidney disease (stages 1-3) due to ADPKD. METHODS AND ANALYSIS: A multicentre, prospective, parallel-group, open-label, randomised controlled trial will be conducted. Patients with ADPKD (n=180; age ≤65 years, estimated glomerular filtration rate (eGFR) ≥30 mL/min/1.73 m2) will be randomised (1:1) to either the control (standard treatment+usual fluid intake) or intervention (standard treatment+prescribed fluid intake) group. Participants in the intervention arm will be prescribed an individualised daily fluid intake to reduce urine osmolality to ≤270 mOsmol/kg, and supported with structured clinic and telephonic dietetic review, self-monitoring of urine-specific gravity, short message service text reminders and internet-based tools. All participants will have 6-monthly follow-up visits, and ht-TKV will be measured by MRI at 0, 18 and 36 months. The primary end point is the annual rate of change in ht-TKV as determined by serial renal MRI in control vs intervention groups, from baseline to 3 years. The secondary end points are differences between the two groups in systemic AVP activity, renal disease (eGFR, blood pressure, renal pain), patient adherence, acceptability and safety. ETHICS AND DISSEMINATION: The trial was approved by the Human Research Ethics Committee, Western Sydney Local Health District. The results will inform clinicians, patients and policy-makers regarding the long-term safety, efficacy and feasibility of prescribed fluid intake as an approach to reduce kidney cyst growth in patients with ADPKD. TRIAL REGISTRATION NUMBER: ANZCTR12614001216606.

Qualitative study of patients and health-care professionals' views on the efficacy of the nutrition as medication oral nutrition supplement program.

AIM: The use of concentrated oral nutrition supplements dispensed in small volumes throughout the day at medication rounds is a common nutrition support strategy. Often termed 'Nutrition as Medication' or NAM, it is associated with excellent rates of patient consumption. However, administration of NAM has been described as suboptimal. The aim of the present study was to identify and explore factors influencing the efficacy of the NAM program from a qualitative perspective. This included exploring issues relating to knowledge, administration and patient consumption from a patient and health professional perspective. METHODS: Semistructured interviews with patients (n = 7) and eight focus groups with nursing, medical, pharmacy and dietetic staff (n = 63) were conducted. Interviews were conducted in the workplace and were recorded and transcribed verbatim. Data were analysed from a realist theoretical position using the thematic framework approach. RESULTS: Five themes were identified that impact on the efficacy of the NAM program. These include the need for clear role delineation among health professionals regarding responsibility for each aspect of NAM. Other themes that emerged included misconceptions about the importance and relevance of the treatment; perceptions of poor palatability and issues associated with the logistics of providing the supplements within the hospital setting. CONCLUSIONS: Dietitians should be aware that there are a range of factors that influence the efficacy of the NAM strategy, including the knowledge and values of individual health professional staff. In addition, increased awareness is required by dietitians regarding the structural barriers to administration and receiving of NAM at the ward level.

Effect of interdisciplinary care on weight loss: a randomised controlled trial.

OBJECTIVE: To determine the effectiveness of a novel interdisciplinary treatment compared with usual care on weight loss in overweight and obese adult volunteers. DESIGN: Single blinded controlled trial. Participants randomly assigned to usual care (C, general guideline-based diet and exercise advice), intervention (I, interdisciplinary protocol) or intervention + a healthy food supplement (30 g walnuts/day) (IW). SETTING: Community based study, Illawarra region, south of Sydney, Australia. PARTICIPANTS: Generally well volunteer adult residents, 25-54 years, body mass index (BMI) 25-40kg/m2 were eligible. At baseline 439 were assessed, 377 were randomised, 298 completed the 3-month intensive phase and 178 completed the 12-month follow-up. INTERVENTIONS: Treatment was provided at clinic visits intensively (0 months, 1 month, 2 months, 3 months) then quarterly to 12 months. Support phone calls were quarterly. All participants underwent blinded assessments for diet, exercise and psychological status. PRIMARY AND SECONDARY MEASURES: The primary outcome was difference in weight loss between baseline and 12 months (clinically relevant target 5% loss). Secondary outcomes were changes in blood pressure, fasting blood glucose and lipids, and changes in diet, exercise and psychological parameters. RESULTS: At 12 months, differences in weight loss were identified (p<0.001). The I group lost more than controls at 3 months (91.11 (92.23,90.00), p<0.05) and the IW more than controls at 3 months (91.25 (92.35,90.15), p<0.05) and 6 months (92.20 (93.90,90.49), p<0.01). The proportion achieving 5% weight loss was significantly different at 3 months, 6 months and 9 months (p=0.04, p=0.03, p=0.03), due to fewer controls on target at 3 months, 6 months and 9 months and more IW participants at 6 months. Reductions in secondary outcomes (systolic blood pressure, blood glucose/lipid parameters and lifestyle measures) followed the pattern of weight loss. CONCLUSIONS: An interdisciplinary intervention produced greater and more clinically significant and sustained weight loss compared with usual care. The intensive phase was sufficient to reach clinically relevant targets, but long-term management plans may be required. TRIAL REGISTRATION NUMBER: ANZCTRN 12614000581662; Post-results.

Medication adherence in randomized controlled trials evaluating cardiovascular or mortality outcomes in dialysis patients: A systematic review.

BACKGROUND: Medication non-adherence is common among renal dialysis patients. High degrees of non-adherence in randomized controlled trials (RCTs) can lead to failure to detect a true treatment effect. Cardio-protective pharmacological interventions have shown no consistent benefit in RCTs involving dialysis patients. Whether non-adherence contributes to this lack of efficacy is unknown. We aimed to investigate how medication adherence and drug discontinuation were assessed, reported and addressed in RCTs, evaluating cardiovascular or mortality outcomes in dialysis patients. METHODS: Electronic database searches were performed in MEDLINE, EMBASE & Cochrane CENTRAL for RCTs published between 2005-2015, evaluating self-administered medications, in adult dialysis patients, which reported clinical cardiovascular or mortality endpoints, as primary or secondary outcomes. Study characteristics, outcomes, methods of measuring and reporting adherence, and data on study drug discontinuation were analyzed. RESULTS: Of the 642 RCTs in dialysis patients, 22 trials (12 placebo controlled), which included 19,322 patients, were eligible. The trialed pharmacological interventions included anti-hypertensives, phosphate binders, lipid-lowering therapy, cardio-vascular medications, homocysteine lowering therapy, fish oil and calcimimetics. Medication adherence was reported in five trials with a mean of 81% (range: 65-92%) in the intervention arm and 84.5% (range: 82-87%) in the control arm. All the trials that reported adherence yielded negative study outcomes for the intervention. Study-drug discontinuation was reported in 21 trials (mean 33.2%; 95% CI, 22.0 to 44.5, in intervention and 28.8%; 95% CI, 16.8 to 40.8, in control). Trials with more than 20% study drug discontinuation, more often yielded negative study outcomes (p = 0.018). Non-adherence was included as a contributor to drug discontinuation in some studies, but the causes of discontinuation were not reported consistently between studies, and non-adherence was listed under different categories, thereby potentiating the misclassification of adherence. CONCLUSIONS: Reporting of medication adherence and study-drug discontinuation in RCTs investigating cardiovascular or mortality endpoints in dialysis patients are inconsistent, making it difficult to compare studies and evaluate their impact on outcomes. Recommendations for consistent reporting of non-adherence and causes of drug discontinuation in RCTs will therefore help to assess their impact on clinical outcomes.

Comparison of the extent and pattern of cognitive impairment among predialysis, dialysis and transplant patients: A cross-sectional study from Australia.

AIM: The aim of this study was to compare the extent of cogntive impairment and the types of cognitive deficits in an Australian cohort of four patient groups with end stage kidney disease. Characteristics predicting the presence of cognitive impairment were also evaluated. METHODS: Observational cross-sectional study of 155 patients with end stage kidney disease are recruited from a regional Australian renal unit. Eligible participants included those whose estimated Glomerular Filtration Rate was < 30 ml/min per 1.73 m2 , were undertaking peritoneal or haemodialysis, or had received a kidney transplant. The Montreal Cognitive Assessment tool was used to screen the study participants for cognitive impairment and evaluate cognitive deficits. Cognitive impairment was defined as a total Montreal Cognitive Assessment tool score ≤24/30. RESULTS: The extent of cognitive impairment varied between the four groups with end stage kidney disease. Factors predicting the presence of cognitive impairment included undertaking dialysis, age ≥65, male gender and the presence of diabetes or cerebrovascular disease. Deficits in executive function, attention, language, visuospatial skills, memory and orientation were common among the study participants, and the extent of these deficits varied between groups. Limitations to the study included the cross-sectional design, and that the presence of confounders like depression were not recorded. CONCLUSION: The impact of disparities in the cognitive capabilities identified in this study are likely to be far reaching. Tailoring of education and self-management programmes to the cognitive deficits of individuals is required.

PREVALENCE OF CONSTIPATION IN PATIENTS WITH ADVANCED KIDNEY DISEASE.

BACKGROUND: For people on peritoneal dialysis (PD), constipation is associated with technique failure. For those on haemodialysis (HD), constipation has been associated with a reduction in quality of life. OBJECTIVES: The objectives of this study were to (i) determine the prevalence of functional constipation; (ii) compare patient perception of constipation with Rome III criteria for functional constipation; (iii) describe the prevalence of constipation and stool form using Bristol Stool Form Scale (BSFS); (iv) determine differences in bowel habit and stool form between those on dialysis compared to pre-dialysis; and (v) determine the diagnostic accuracy of self-perception and the Rome III criteria against the BSFS. A cross-sectional group of pre-dialysis (eGFR < 15 ml/min) and dialysis patients were recruited. A total of 148 patients participated (98 HD, 21 PD and 21 pre-dialysis). PARTICIPANTS: completed a questionnaire consisting of self-perception of the presence of constipation, simplified questions from the Rome III criteria for functional constipation, scored their stool form using the BSFS and reported laxative use. RESULTS: The prevalence of constipation using the Rome III criteria was 12.3%; patient perception 46.3% and 25.7% using the BSFS. Prevalence differed according to the tool used. CONCLUSION: No single method alone is sufficient for accurately determining if a patient is constipated. Relying on patients' self-perception may be unreliable. Ideally patient assessment of constipation should incorporate both the Rome III criteria and BSFS in a method such as the one designed as a result of this research. Further research is needed to assess its usability and practicality in clinical practice.

Interdisciplinary lifestyle intervention for weight management in a community population (HealthTrack study): Study design and baseline sample characteristics.

BACKGROUND: Integrating professional expertise in diet, exercise and behavioural support may provide more effective preventive health services but this needs testing. We describe the design and baseline results of a trial in the Illawarra region of New South Wales, Australia. METHODS: The HealthTrack study is a 12 month randomised controlled trial testing effects of a novel interdisciplinary lifestyle intervention versus usual care. The study recruited overweight and obese adults 25-54 years resident in the Illawarra. Primary outcomes were weight, and secondary outcomes were disease risk factors (lipids, glucose, blood pressure), and behaviour (diet, activity, and psychological factors). Protocols, recruitment and baseline characteristics are reported. RESULTS: Between May 2014 and April 2015, 377 participants were recruited and randomised. The median age (IQR) of the mostly female sample (74%) was 45 (37-51) years. The sample comprised obese (BMI 32 (29-35) kg/m(2)) well educated (79% post school qualifications) non-smokers (96%). A high proportion reported suffering from anxiety (26.8%) and depression (33.7%). Metabolic syndrome was identified in 34.9% of the sample. CONCLUSIONS: The HealthTrack study sample was recruited to test the effectiveness of an interdisciplinary approach to preventive healthcare in self-identified overweight adults in the Illawarra region. The profile of participants gives some indication of those likely to use services similar to the trial design.