A Proposed Predictive Equation for Energy Expenditure Estimation Among Noncritically Ill Patients With Acute Kidney Injury.

OBJECTIVE: The incidence of acute kidney injury (AKI) is identified more frequently in noncritical compared with intensive care settings. The prognosis of malnourished AKI patients is far worse than those with normal nutritional status. However, a method for estimating the optimal amount of energy required to guide nutritional support among noncritically ill AKI patients is yet to be determined. METHODS: We evaluated the performance of weight-based formulas (20-30 kcal/kg/day) with the reference values of energy expenditure (EE) measured by indirect calorimetry (IC) among noncritically ill AKI patients during hospitalization. The statistics for assessing agreement, including total deviation index and accuracy within 10% represent the percentage of estimations falling within the IC value range of ±10%, were tested. Parameters for predicting the EE equation were also developed using a regression analysis model. RESULTS: A total of 40 noncritically ill AKI patients were recruited. The mean age of participants was 62.5 ± 16.5 years with 50% being male. The average IC-derived EE was 1,124.6 ± 278.9 kcal/day with respiratory quotients 0.8-1.3, indicating good validity of the IC test. Receiving dialysis, protein catabolic rate, and age was not significantly associated with measured EE. Nearly all weight-based formulas overestimated measured EE. The magnitude of total deviation index values was broad with the proportion of patients achieving an accuracy of 10% being as low as 20%. The proposed equation to predict EE derived from this study was EE (kcal/day) = 618.27 + (8.98 x weight in kg) + 137.0 if diabetes - 199.7 if female (r2 = 0.68, P < .001). In the validation study with an independent group of noncritically ill AKI patients, predicted EE using the newly derived equation was also significantly correlated with measured EE by IC (r = 0.69, P = .004). CONCLUSION: Estimation of EE by weight-based formulas usually overestimated measured EE among noncritically ill AKI patients. In the absence of IC, the proposed predictive equation, specifically for noncritically ill AKI patients might be useful, in addition to weight-based formulas, for guiding caloric dosing in clinical practice.

Exploring hospital practice types and their impact on glomerular pathologic patterns: Insights from the largest kidney biopsy cohort in Thailand.

BACKGROUND: This study aims to investigate the influence of different kidney biopsy practices on the prevalence of glomerular pathologic patterns in the largest kidney biopsy registry in Thailand. METHODS: We conducted a retrospective review of kidney biopsy records from the period between 2000 and 2014. The records were obtained from 2 major institutions: King Chulalongkorn Memorial Hospital, a large university-based hospital, and the Kidney Center Bangkok Hospital, which provides pathology services to hospitals throughout Thailand. The study included native kidney biopsies from all provinces in Thailand, excluding paediatric patients, kidney transplant recipients, and cases of inadequate and repeated biopsies. Patient demographics, indications for biopsy, and final glomerular diagnoses were compared across different hospital practice settings: university (UVH), private (PVH) and public (PBH). RESULTS: A total of 5893 eligible native kidney biopsies were identified from a pool of 7005 biopsies conducted over a 15-year period in 25 provinces throughout Thailand. The 3 most common indications for biopsy were suspected kidney involvement in systemic lupus erythematosus (SLE) (29%), nephrotic syndrome (NS) (29%), and acute glomerulonephritis (AGN)/rapidly progressive glomerulonephritis (RPGN) (13%). The leading indication for biopsy differed across practice types, with suspected kidney involvement in SLE being the primary indication in UVH, while NS took precedence in both PBH and PVH practices. Notably, UVH performed fewer kidney biopsies for asymptomatic urinary abnormalities and diabetes-related indications compared with PVH and PBH. The leading glomerular diagnoses correlated with the biopsy indications, with lupus nephritis (LN) being the most common diagnosis in UVH and PBH practices, whiles immunoglobulin A nephropathy was the predominant diagnosis in PVH practice. CONCLUSION: Hospital practice types significantly impact the prevalence of glomerular pathologic diagnosis patterns in kidney biopsy data, highlighting the importance of considering this influence in epidemiological comparisons.

Calf circumference as a screening tool for low skeletal muscle mass: Cut-off values in independent Thai older adults.

BACKGROUND: Calf circumference is recommended as a marker for low muscle mass and as a case finding in the diagnosis of sarcopenia. However, the cut-off value differed by ethic and region. Currently there is no study among Thai population. Therefore, we aimed to identify the optimal cutoff value of calf circumference as a screening tool for low skeletal muscle mass in independent Thai older adults. Subgroup analysis was performed for obesity and adults over 75 years. METHODS: This cross-sectional cohort studied in an outpatient geriatric check-up clinic. Participants, aged 60 and above, needed to be independent in basic activities of daily living to meet the inclusion criteria. Exclusion criteria comprised active malignancy, cardiac, pulmonary, or neurovascular diseases necessitating hospitalization in the preceding three months, chronic renal diseases requiring renal replacement therapy, and unstable psychiatric disorders. We measured the maximum calf circumference and appendicular skeletal muscle mass (ASMI) using bioelectrical impedance analysis (BIA). Low muscle mass is defined according to the Asian Working Group of Sarcopenia (AWGS) 2019 consensus. RESULTS: We enrolled 6,404 elderly adults (mean age 67.3 ± 5.1 years), with a 47% prevalence of low muscle mass in women and 25% in men. Lower muscle mass significantly correlated with reduced BMI and waist circumference in both genders (p < 0.001). Optimal cut-off values for low muscle mass screening were < 33 cm (sensitivity 80.1%, specificity 60.5%) for women and < 34 cm (sensitivity 85.4%, specificity 70.2%) for men. Subgroup analysis for those with BMI ≥ 25 kg/m² suggested raising the cut-off for women to < 34 cm (sensitivity 80.6%, specificity 54.0%) and for men to < 35 cm (sensitivity 88.7%, specificity 55.2%) to enhance specificity without substantial sensitivity loss. In the older-old adult subgroup (≥ 75 years), optimal cut-off values were < 33 cm (sensitivity 84.6%, specificity 79.9%) for women and < 34 cm (sensitivity 75.6%, specificity 87.0%) for men. CONCLUSIONS: There is a strong correlation between calf circumference and ASMI in independent Thai older adults. Calf circumference can serve as a screening tool for identifying low muscle mass. The recommended cut-off values for men and women are 34 cm and 33 cm, respectively in alignment with AWGS 2019 recommendation. Incorporating a 1-cm higher cut-off value for obese older adults improves the accuracy of muscle mass screening. TRIAL REGISTRATION: Thai clinical trial registry: TCTR20200511003.

Longitudinal Assessment of Body Composition and Its Association With Survival Among Participants of the ACTIVE/ADIPOSE Study.

OBJECTIVES: The importance of muscle wasting as a predictor of mortality in the hemodialysis population is not clear. Lack of association of muscle mass with survival in some studies could be related to reliance on single measures or to incorporation of excess extracellular water (ECW) into estimates of muscle mass. We examined changes in body composition over a 2-year period and the association of body composition with survival. DESIGN AND METHODS: We analyzed data from 325 adults receiving hemodialysis in the Bay Area. We estimated ECW, intracellular water (ICW), and fat mass by whole-body bioimpedance spectroscopy (BIS) at 0, 12, and 24 months from enrollment. We used linear mixed modeling to examine changes in body mass index and BIS-derived estimates of body composition and Cox modeling with BIS-derived estimates as time-varying independent variables to examine associations between body composition and survival in multivariable analyses. RESULTS: Body mass index declined over time. Considering individual components of body composition, ICW declined (-0.09 kg/m2 per year, 95% confidence interval -0.14 to -0.04), but fat mass and ECW did not change significantly. There were 120 deaths over a median of 5.2 years. The relationship between ICW and mortality was not linear such that the association was steeper at low values of ICW, whereas higher ICW was associated with better survival that was relatively stable above 9 kg/m2. Higher ECW was associated with higher mortality, and fat mass was not associated with survival. These associations were independent of markers of inflammation and nutritional status. CONCLUSIONS: ICW declined over 2 years in this cohort, whereas fat mass and ECW remained relatively stable. Higher ICW was associated with better survival, but higher fat mass was not. Higher ECW was associated with worse survival. These results suggest that muscle mass may predict survival among patients on hemodialysis.

Association of Cognitive Function Screening Results with Adherence and Performance in a Pedometer-Based Intervention.

INTRODUCTION: A randomized, controlled trial of a pedometer-based walking intervention with weekly activity goals led to increased walking among dialysis patients. We examined whether impairment per cognitive function screening is associated with adherence and performance in the intervention. METHODS: Thirty dialysis patients were randomly assigned to a 3-month pedometer-based intervention with weekly goals. Participants were administered the Telephone Interview of Cognitive Status (TICS), a test of global mental status. We examined the association of levels of impairment on the TICS (≥33: unimpaired, 26-32: ambiguous impairment, 21-25: mild cognitive impairment [MCI]) with adherence, achieving weekly goals, and increasing steps, physical performance (Short Physical Performance Battery, SPPB), and self-reported physical function (PF) through multivariable linear mixed-model and logistic regression analyses adjusted for age, sex, BMI, dialysis modality, baseline steps, baseline SPPB, and stroke status. RESULTS: One-third of participants were unimpaired, and 13% had MCI. Participants with worse results on cognitive function screening missed more calls and completed fewer weekly goals than participants with better results. During the intervention, a worse result on cognitive function screening was associated with smaller increases in steps compared to those without impairment: (ambiguous: -620 [95% CI -174, -1,415], MCI: -1,653 [95% CI -120, -3,187]); less improvement in SPPB (ambiguous: -0.22 points [95% CI -0.08, -0.44], MCI: -0.45 [95% CI -0.13, -0.77]); and less improvement in PF (ambiguous: -4.0 points [95% CI -12.2, 4.1], MCI: -14.0 [95% CI -24.9, -3.1]). During the postintervention period, a worse result on cognitive function screening was associated with smaller increases in SPPB (ambiguous: -0.54 [95% CI -1.27, 0.19], MCI: -0.97 [95% CI -0.37, -1.58]) and PF (ambiguous: -3.3 [95% CI -6.5, -0.04], MCI: -10.5 [95% CI -18.7, -2.3]). DISCUSSION/CONCLUSION: Participants with worse results on cognitive function screening had worse adherence and derived less benefit from this pedometer-based intervention. Future exercise interventions should be developed incorporating methods to address cognitive impairment, for example, by including caregivers when planning such interventions.

Association between self-reported appetite and clinical outcomes of peritoneal dialysis patients: Findings from a low middle-income country.

AIM: Patient-reported outcome measures (PROM) has gained international recognition as important predictors of clinical outcomes in peritoneal dialysis (PD). We sought to understand the associations between patient-reported appetite and clinical outcomes. METHODS: In the Thailand Peritoneal Dialysis Outcomes and Practice Patterns Study (PDOPPS), 690 of 848 randomly selected PD patients from 22 facilities reported their appetite by using the short form (three items) of the Appetite and Diet Assessment Tool (ADAT), between 2016 and 2018. In this questionnaire, the patients rated their appetite as well as a change in appetite over time. Cox proportional hazards model regression was used to estimating associations between self-reported appetite and clinical outcomes, including mortality, haemodialysis (HD) transfer and peritonitis. RESULTS: Half of the PD patients reported a good appetite, whereas 34% and 16% reported fair and poor appetites, respectively. Poor appetite was more prevalent among female, diabetic, congestive heart failure, older age and patients who had worse nutritional indicators, including lower time-averaged serum albumin and serum creatinine concentrations, as well as a higher proportions of hypokalaemia and severe hypoalbuminemia (serum albumin <3 g/dl). After adjusting for age, sex, comorbidities, and PD vintage, poor appetite was associated with increased risks of peritonitis (adjusted hazard ratio [HR] 1.73, 95% confidence interval [CI] 1.14-2.62), HD transfer (adjusted HR 2.25, 95% CI 1.24-4.10) and all-cause mortality (adjusted HR 1.60, 95% CI 1.08-2.39) compared to patients with good appetite. CONCLUSION: Patient-reported poor appetite was independently associated with higher risks of peritonitis, HD transfer and all-cause mortality. This warrants further investigation to identify effective interventions.

Protein-Energy Wasting and Mortality Risk Prediction Among Peritoneal Dialysis Patients.

OBJECTIVES: Protein-energy wasting (PEW) is defined as the loss of body protein and energy reserves associated with kidney disease. However, the extent to which PEW contributes to increased mortality among peritoneal dialysis (PD) patients remains unclear. METHODS: This is a retrospective cohort study from 2012 to 2020. The PEW was diagnosed by applying at least 3 of the 4 following criteria: (1) altered serum biochemistry indicated by a serum albumin level of <3.5 g/L; (2) decreased body mass status identified by a body mass index (BMI) of <23 kg/m2 or <10% total body fat; (3) muscle wasting defined by the lean tissue index, calculated as a lean tissue mass normalized to the height-squared in the <10th percentile of the reference population; and (4) low dietary protein intake determined by the normalized protein equivalent of a total nitrogen appearance of <0.8 g/kg/day. The Malnutrition Inflammation Score (MIS) was also examined as an alternative tool for assessment of PEW. RESULTS: The average age of the 555 participants was 57.5 ± 12.6 years. The prevalence of PEW was 27.3%, with 196 deaths observed during the mean follow-up of 25.5 months. Patients with PEW who fulfilled at least 3 of the 4 listed criteria had a higher risk of death in the unadjusted model (hazard ratio 1.61, 95% confidence interval 1.19-2.18, P = .002). However, these associations were attenuated after adjusting for potential confounders. Regarding the individual PEW criterion, decreased serum albumin and low muscle mass were significantly associated with mortality in the multivariable models. In contrast, decreased body mass and low protein intake were not associated with a higher risk of death. High MIS (≥5 points) and each one-point increase in the MIS were also significantly associated with higher risk of death in both unadjusted and adjusted models. CONCLUSIONS: Among PD patients, the presence of PEW was not a better predictor of all-cause mortality than either the altered serum biochemistry (albumin) or low muscle mass criteria. The MIS performed well as an independent predictor of death and might be an option for assessment of PEW status in the PD population.

A Walking Intervention to Increase Weekly Steps in Dialysis Patients: A Pilot Randomized Controlled Trial.

RATIONALE & OBJECTIVE: Patients receiving dialysis report very low physical activity. We implemented a pilot trial to assess the feasibility of a pedometer-based intervention to gather preliminary evidence about its impact on physical activity, symptoms, and surrogates of cardiovascular risk. STUDY DESIGN: Pilot randomized controlled trial. SETTING & PARTICIPANTS: 60 dialysis patients from San Francisco dialysis clinics. INTERVENTION: Participants were randomly assigned 1:1 to receiving pedometers with weekly step goals or usual care for 3 months. OUTCOMES: The primary outcome was step counts, measured using pedometers. Secondary outcomes included physical performance using the Short Physical Performance Battery, the Physical Function and Vitality scales of the 36-Item Short Form Health Survey, the Dialysis Symptoms Index, and the Center for Epidemiologic Studies-Depression Scale, with endothelial function as a secondary and heart rate variability as an exploratory surrogate measure of cardiovascular risk. Targeted enrollment was 50% and targeted completion was 85%. RESULTS: 49% of approached patients were enrolled, and 92% completed the study. After 3 months, patients randomly assigned to the intervention (n=30) increased their average daily steps by 2,256 (95% CI, 978-3,537) more than the 30 controls (P<0.001). Heart rate variability (standard deviation of N-N intervals) increased by 14.94 (95% CI, 0.31-33.56) millisecondsin the intervention group as compared with controls (P = 0.05). There were no statistically significant differences across intervention groups in symptoms, physical performance, or endothelial function. Participants in the intervention group reverted to baseline steps during the postintervention follow-up. LIMITATIONS: The Northern California study setting may limit generalizability. Walking does not capture the full spectrum of physical activity. CONCLUSIONS: A short-term pedometer-based intervention led to increased step counts in dialysis patients, but the increase was not sustained. Pedometer-based interventions are feasible for dialysis patients, but future studies are needed to address whether more prolonged interventions can improve physical function or symptoms. FUNDING: Supported by grants from the American Kidney Fund, National Institutes of Health-National Institute of Diabetes and Digestive and Kidney Diseases, and International Society of Nephrology. TRIAL REGISTRATION: Registered at ClinicalTrials.gov with study identifier NCT02623348.

Impact of Serum Bicarbonate Levels on Muscle Mass and Kidney Function in Pre-Dialysis Chronic Kidney Disease Patients.

BACKGROUND: Treatment of metabolic acidosis to target the higher serum bicarbonate level than guideline recommendation may downregulate muscle protein degradation and improve renal function among chronic kidney disease (CKD) patients. We conducted a study to test the effects of increased serum bicarbonate level on muscle parameters, nutrition, and renal function in pre-dialysis CKD patients. METHODS: This was a randomized, controlled study. CKD stage 3-4 patients with serum HCO3- <22 mEq/L were randomized to either receive oral sodium bicarbonate with high target bicarbonate level of 25 ± 1 or standard level of 22 ± 1 mEq/L as control group using protocol-based titration of dosage adjustment. The changes of muscle mass measured by bioelectrical impedance analysis (BIA), muscle strength by hand grip dynamometer, estimated glomerular filtration rate (eGFR) using CKD-Epidemiology Collaboration equation, nutritional markers, and muscle-related biomarkers were determined. Data at baseline and after 4 months of sodium bicarbonate supplementation were compared between groups using Student t test or chi-square test as appropriate. RESULTS: Forty-two patients completed the study (n = 21 per group). The mean age and eGFR were 61.2 ± 9.8 years and 32.4 ± 14.1 mL/min respectively. Serum bicarbonate levels at baseline were 21.0 ± 2.1 mEq/L. Baseline data including sex, diabetes, serum bicarbonate level, creatinine, and blood pressure were similar. After 4 months of treatment, the average serum bicarbonate levels in both groups were 24.0 ± 1.4 and 20.7 ± 2.3 mEq/L (p < 0.001). Both BIA-derived total-body muscle mass and appendicular lean balance were increased at 4 months in the higher bicarbonate group (26.0 ± 5.3 to 26.7 ± 5.5 kg, p = 0.04 and 19.8 ± 4.1 to 20.7 ± 4.4 kg, p = 0.06, respectively) despite comparable body weight and protein intake. Patients in the high bicarbonate group had a significant reduction of plasma myostatin levels, a surrogate of muscle degradation, at the study exit after adjusting for baseline values (-3,137.8; 95% CI -6,235.3 to -40.4 pg/mL, p= 0.04), but unaltered insulin-like growth factor-1 level, as the mediator of muscle cell growth, (141 [106-156] to 110 [87-144] ng/mL, p = 0.13) compared to the control group. Muscle strength, eGFR as well as serum prealbumin were not significantly different between 2 groups (p > 0.05). Neither worsening hypertension nor congestive heart failure was found throughout the study. CONCLUSION: Bicarbonate supplementation to achieve the serum level ∼24 mEq/L demonstrates better muscle mass preservation in patients with pre-dialysis CKD. The impact of alkaline therapy on renal function may require a longer period of study.

Association of motivations and barriers with participation and performance in a pedometer-based intervention.

BACKGROUND: A randomized trial of a pedometer-based intervention with weekly activity goals led to increased walking among dialysis patients. However, the association of participant-expressed motivations and barriers to participation and performance in such an intervention has not been determined. METHODS: Thirty dialysis patients were randomized to a 12-week pedometer-based intervention with weekly step goals. Participants were asked about motivations and barriers to the increasing activity via weekly semi-scripted telephone interviews. We examined the association of these motivations and barriers with achieving weekly goals, reaching overall targets and increasing steps through multivariable linear and logistic regression analyses adjusted for age, sex, body mass index, dialysis modality and baseline steps. RESULTS: The most common motivations were desire to maintain/improve functional ability (30%) and activity (30%). The most common barriers were health-related (33%). Motivation to maintain/improve functional ability was associated with achieving weekly goals 17.9% more often [95% confidence interval (CI) 1.7-34.2] and with a greater increase in steps (1524 steps; 95% CI 61-2989) than those lacking this motivation. Experiencing a health-related barrier was not associated with the decreased achievement of weekly goals but was associated with lower odds of reaching overall targets (odds ratio = 0.06; 95% CI 0.01-0.53) and a smaller increase in steps (-1640 steps, 95% CI -3244 to -36). No patients who reported weather/environmental barriers or safety concerns reached overall targets. CONCLUSIONS: Participants who express a desire to maintain/improve functional ability may be particularly suited for activity interventions. Health-related setbacks should be met with revised goals. Reporting environmental or safety concerns may merit lowering overall targets.

Effect of a pedometer-based walking intervention on body composition in patients with ESRD: a randomized controlled trial.

BACKGROUND: A randomized trial of a pedometer-based intervention with weekly activity goals led to a modest increase in step count among dialysis patients. In a secondary analysis, we investigated the effect of this intervention on body composition. METHODS: Sixty dialysis patients were randomized to standard care or a 6-month program consisting of 3 months of pedometers and weekly step count targets and 3 months of post-intervention follow-up. We obtained bioelectrical impedance spectroscopy (BIS) data on 54 of these patients (28 control, 26 intervention) and used linear mixed-modeling (adjusted for sex and dialysis modality) to estimate differences in change in total-body muscle mass (TBMM) adjusted for height2, fat mass (kg), and body mass index (BMI) (kg/m2) between control and intervention groups. RESULTS: The median age of participants was 57.5 years (53-66), and 76% were men. At baseline, there was no significant difference between groups in age, BMI, race, or body composition, but there were more men in the intervention group. After 3 months, patients in the intervention group increased their average daily steps by 2414 (95% CI 1047, 3782) more than controls (p < 0.001), but there were no significant differences in body composition. However, at 6 months, participants in the intervention had a significantly greater increase from baseline in TBMM of 0.7 kg/m2 (95% CI 0.3, 1.13), decrease in fat mass (- 4.3 kg [95% CI -7.1, - 1.5]) and decrease in BMI (- 1.0 kg/m2 [95% CI -1.8, - 0.2]) relative to controls. In post-hoc analysis, each increase of 1000 steps from 0 to 3 months was associated with a 0.3 kg decrease in fat mass (95% CI 0.05, 0.5) from 0 to 6 months, but there was no dose-response relationship with TBMM/ht2 or BMI. CONCLUSION: A pedometer-based intervention resulted in greater decreases in fat mass with relative preservation of muscle mass, leading to a greater decrease in BMI over time compared with patients not in the intervention. These differences were driven as much by worsening in the control group as by improvement in the intervention group. Step counts had a dose-response relationship with decrease in fat mass. TRIAL REGISTRATION: ClinicalTrials.gov (NCT02623348). 02 December 2015.

The Effects of Restricted Protein Diet Supplemented With Ketoanalogue on Renal Function, Blood Pressure, Nutritional Status, and Chronic Kidney Disease-Mineral and Bone Disorder in Chronic Kidney Disease Patients: A Systematic Review and Meta-Analysis.

OBJECTIVE: To systemically review the meta-analysis exploring the effectiveness and safety of restricted protein diet supplemented with ketoanalogues (KAs) when compared with regular diet or low protein diet (LPD) without KAs in chronic kidney disease (CKD) patients. STUDY DESIGN AND METHODS: We conducted electronic searches in PubMed, Scopus, Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov from January 1960 to May 2018 to identify randomized controlled clinical trials that explored the effects of restricted protein diet including vegetarian and mixed type of protein with KAs on kidney endpoints including the changes in estimated glomerular filtration rate (eGFR) and proteinuria, nutritional status, and CKD-mineral bone disorder. RESULTS: Seventeen RCTs with 1,459 participants were included in our meta-analysis. Restricted protein diet with KAs significantly preserved eGFR and reduced proteinuria, serum phosphate, parathyroid hormone (PTH) level, systolic blood pressure, diastolic blood pressure, and serum cholesterol. By subgroup analysis, very low protein diet (VLPD) with KAs was plausibly superior to LPD with KAs in slowing the decline in eGFR. Only VLPD with KAs significantly improved serum PTH, systolic blood pressure, and diastolic blood pressure while both regimens significantly decreased serum phosphate. Only LPD with KAs significantly raised serum albumin and serum calcium. CONCLUSION: Restricted protein diet supplemented with KAs could effectively improve kidney endpoints including preserving eGFR and diminishing proteinuria, blood pressure levels, and CKD-mineral bone disorder parameters without causing malnutrition. VLPD with KAs appears to provide more effectiveness in slowing the decline in eGFR, lowering blood pressure, reducing serum PTH, and less increasing serum calcium level.

The obesity paradox: A further consideration in dialysis patients.

Several epidemiological cohorts have demonstrated that higher body mass index (BMI) is associated with lower mortality risk among patients receiving hemodialysis. However, BMI may be an inaccurate indicator of nutritional status among dialysis patients because it does not differentiate between muscle and fat mass or provide information about body fat distribution. More sophisticated methods of body composition analysis are therefore required to address the question of which component is associated with greater survival. Recent evidence has also shown that changes in body weight and body composition are more strongly associated with mortality in dialysis patients than measurement of BMI at a single time point. Given that obesity is common among the dialysis population, weight loss interventions are encouraged for obese dialysis patients who are on a transplant waiting list in order to increase the access for transplantation.

Validation of a New Physical Activity Instrument Against Pedometers Among Dialysis Patients.

OBJECTIVE(S): The newly developed Low Physical Activity Questionnaire (LoPAQ) was designed to capture the low activity level among typically sedentary patients undergoing dialysis and correlated well with a physical activity questionnaire used in the general population. However, this instrument has not been validated against a more objective measure. METHODS: We recruited patients receiving dialysis for ≥3 months from 3 dialysis facilities in San Francisco. Spontaneous walking activity was measured by pedometers over 7 days including a weekend and used as the standard reference. Patients were instructed to record their activities and step count readings. Study coordinators administered the LoPAQ during a dialysis session (hemodialysis [HD]) or clinic visit (peritoneal dialysis [PD]). The LoPAQ ascertains time and energy expended in walking activity, as well as light, moderate, and vigorous activity, and total physical activity during a 1-week recall period with 11 simple questions and requires approximately 10 minutes to administer. The LoPAQ also asks about time spent in sitting activities over 1 week. Spearman correlation was used to determine whether the LoPAQ results correlate with step counts. RESULTS: Sixty dialysis patients (HD = 48, PD = 12) completed the LoPAQ and wore a pedometer for 1 week. Mean age was 58.0 ± 12.7 years, 78.3% were men, and median dialysis vintage was 3.1 (IQR, 1.1-5.8) years. Median step count was 2,630.5 (1,270.7-5,137) steps/day. Most patients (82.8%) reported walking activity around the neighborhood, for transportation, and/or for fitness or pleasure, with a median of 595 (70-1,566.3) kcal/week. Total kilocalories per week of physical activity reported on the LoPAQ were 655 (422.8-2,336.8). Participants reported an average of 5 (3-8) sedentary hours per day. Energy expenditure in walking by the LoPAQ was highly correlated with weekly step counts (rho = 0.53, P < .001). In addition, the overall activity reported on the LoPAQ correlated with weekly pedometer readings (rho = 0.35, P = .01) and did not differ between HD and PD patients. CONCLUSIONS: The LoPAQ was easier and less time-consuming than previously validated physical activity questionnaires. LoPAQ demonstrated a good correlation with objective pedometer step counts among dialysis patients, similar to other physical activity instruments used in healthier and more active populations.

Sarcopenia and its individual criteria are associated, in part, with mortality among patients on hemodialysis.

The relative importance of sarcopenia and its individual components as independent predictors of mortality in the dialysis population has not been determined. We estimated whole-body muscle mass using pre-dialysis bioimpedance spectroscopy measurements in 645 ACTIVE/ADIPOSE-enrolled prevalent hemodialysis patients from San Francisco and Atlanta. Low muscle mass was defined as two standard deviations below sex-specific means for young adults from NHANES and indexed to height2, body weight, body surface area, or body mass index. We evaluated the association of sarcopenia (low muscle mass) by four indexing methods, weak hand grip strength, and slow gait speed with mortality. Seventy-eight deaths were observed during a mean follow-up of 1.9 years. Sarcopenia was not significantly associated with mortality after adjusting for covariates. No muscle mass criteria were associated with death, regardless of indexing metrics. In contrast, having weak grip strength or slow walking speed was associated with mortality in the adjusted model. Only gait slowness significantly improved the predictive accuracy for death with an increase in C-statistic from 0.63 to 0.68. However, both gait slowness and hand grip weakness significantly improved the net reclassification index compared to models without performance measures (50.5% for slowness and 33.7% for weakness), whereas models with muscle size did not. Neither sarcopenia nor low muscle mass by itself was a better predictor of mortality than functional limitation alone in patients receiving hemodialysis. Thus, physical performance measures, including slow gait speed and weak hand grip strength, were associated with mortality even after adjustment for muscle size and other confounders.

The beneficial effects of weight reduction in overweight patients with chronic proteinuric immunoglobulin a nephropathy: a randomized controlled trial.

OBJECTIVE: This study was conducted to examine the effects of weight reduction on proteinuria, adipokines, and renal function in overweight immunoglobulin A nephropathy (IgAN) patients (body mass index > 23 kg/m2) with chronic proteinuria more than 6 months. DESIGN: This was a single-center, prospective, randomized controlled trial. The study was performed at the outpatient clinic at King Chulalongkorn Memorial Hospital, Bangkok, Thailand, from July 2012 to February 2013. SUBJECTS: Twenty-six overweight patients with chronic proteinuric biopsy-proven IgAN were randomized into a control group (n = 13) or a low-calorie normal protein diet group (n = 13). All patients received the maximum dosage of angiotensin-converting enzyme inhibitor or angiotensin receptor blocker and other antihypertensive agents to achieve a blood pressure less than 125/75 mmHg. INTERVENTION: The study intervention was a low-calorie diet (target energy per day as 500-kcal subtraction from total energy requirement) for a 6-month period. MAIN OUTCOME MEASURE: At baseline and after 6 months of a low-calorie diet, body weight, body content, and clinical and laboratory parameters were determined and compared. RESULTS: After initiating a low-calorie diet for 6 months, the normalized protein nitrogen appearance values were not different, indicating comparable protein intake. The low-calorie group had lower total daily calorie intake (1,307.1 ± 171.8 vs. 1,772.2 ± 315.4 kcal/d, P < .01) and significant reductions in body weight (-5.1 ± 3.3%, P < .001), fat content (-12.7 ± 14.1%, P < .05), and 24-hour urine protein (-45.2 ± 15.4%, P < .001). Blood pressure and renal function parameters were unaltered. The low-calorie group had approximately 20% lower plasma levels of leptin but unchanged adiponectin. There were positive correlations between the amount of protein reduction and the changes of body weight, fat mass, and leptin. CONCLUSIONS: A 6-month low-calorie diet leads to weight reduction and results in diminished fat content and decreased proteinuria in overweight IgAN patients with chronic proteinuria. This beneficial effect might be mediated by changes in adipokines.

Plant-based diets in patients with chronic kidney disease.

Dietary protein restriction has been considered to be a nutritional-related strategy to reduce risk for end-stage kidney disease among patients with non-dialysis-dependent chronic kidney disease (CKD). However, there is insufficient evidence to recommend a particular type of protein to slow down the CKD progression. Recently, various plant-based diets could demonstrate some additional benefits such as a blood pressure-lowering effect, a reduction of metabolic acidosis as well as hyperphosphatemia, and gut-derived uremic toxins. Furthermore, the former concerns about the risk of undernutrition and hyperkalemia observed with plant-based diets may be inconsistent in real clinical practice. In this review, we summarize the current evidence of the proposed pleiotropic effects of plant-based diets and their associations with clinical outcomes among pre-dialysis CKD patients.

The role of a low protein diet supplemented with ketoanalogues on kidney progression in pre-dialysis chronic kidney disease patients.

In slowing kidney progression, numerous pre-dialysis chronic kidney disease (CKD) patients could not adhere to the well-established dietary pattern, including a very low protein diet, 0.3-0.4 g/kg/day, plus a full dose ketoanalogues (KAs) of amino acids. We evaluated the role of a low protein diet (LPD), 0.6-0.8 g/kg/day, combined with KAs (LPD-KAs) on CKD progression. We extracted data in the retrospective cohort using electronic medical records (n = 38,005). Participants with LPD-KAs for longer than six months were identified. An unmatched control group, LPD alone, was retrieved from the same database. Cox proportional hazard models were performed to examine the associations between LPD-KAs and outcomes. The primary outcome was either a rapid estimated glomerular filtration rate (eGFR) decline > 5 mL/min/1.73m2/year or commencing dialysis. Other secondary outcomes include changes in proteinuria, serum albumin, and other metabolic profiles were also assessed. A total of 1042 patients were finally recruited (LPD-KAs = 543). Although patients with LPD-KAs had significantly lower eGFR and a prevalence of diabetes, age, and dietary protein intake were comparable between LPD-KAs (0.7 ± 0.2 g/kg/day) and LPD alone groups (0.7 ± 0.3 g/kg/day, p = 0.49). During a median follow-up of 32.9 months, patients treated with LPD-KAs had a significantly lower risk of kidney function decline (HR 0.13; 95% CI 0.09-0.19, p < 0.001) and dialysis initiation (HR 0.24; 95% CI 0.12-0.49, p < 0.001) than LPD alone after adjusting for confounders. The annual rate of eGFR decline in patients receiving LPD-KAs was 4.5 [3.4-5.5] mL/min/1.73m2 compared with 7.7 [6.0-9.4] mL/min/1.73m2 in LPD alone (p = 0.001). According to KAs dose-response analysis, the daily dose of ≤ 5 tablets was conversely associated with a higher risk of the primary endpoint, whereas the association disappeared among patients receiving a dose of > 6 tablets. The spot urine protein creatinine ratio and serum phosphate levels were not significantly different between groups. LPD-KAs could retard kidney progression compared with LPD alone. This favorable effect was significant among CKD patients receiving a daily KAs dose of more than six tablets. Future randomized controlled trials should be performed to verify these findings.

Association analysis of body composition with survival among prevalent peritoneal dialysis patients.

PURPOSE: Progressive decline in lean mass and gain of fat mass are common in patients treated with peritoneal dialysis (PD). It is unclear whether body composition or its longitudinal changes contribute to increased mortality among prevalent PD patients. METHODS: This was a retrospective cohort study. Body composition was assessed using bioelectrical impedance spectroscopy (BIS). Lean and fat tissue indices were derived from lean and fat mass indexed to height-squared, respectively. The patient's baseline BIS results were used to explore its mortality risk prediction for the entire cohort. Among patients with subsequent BIS measurements, changes of lean and fat mass over time were also examined with survival outcomes. RESULTS: Among all participants (n = 555, PD vintage 38 months), higher baseline lean tissue index was associated with lower mortality after adjusting for fat tissue index and confounders (HR 0.90; 95% CI 0.84-0.97, p = 0.01). However, this association was no longer significance after the final adjustment with serum albumin level (p = 0.06). A total of 136 patients had repeated BIS data. After the interval of 10.1 months during two consecutive BIS measurements, there was a strong inverse correlation between the percentage changes of lean and fat tissue indices (r = - 0.73, p < 0.001). The longitudinal changes in lean mass, either high or low categories, were not significantly associated with all-cause mortality. In contrast, patients who were classified as having low values of fat tissue index (below median) from baseline to the next BIS measurements had a lower odds of death in the univariable (HR 0.32; 95% CI 0.12-0.84, p = 0.02) but not in the adjusted models. CONCLUSION: Among prevalent PD patients, higher baseline lean mass was independently associated with better survival. However, the longitudinal changes in lean mass were not significantly associated with mortality. In contrast, the maintenance of low fat status over time appeared to be associated with a lower likelihood of death among PD population.

The beneficial effects of intradialytic parenteral nutrition in hemodialysis patients with protein energy wasting: a prospective randomized controlled trial.

In hemodialysis (HD) patients, protein-energy wasting (PEW) is highly prevalent and firstly treated with oral nutritional supplements (ONS). The extent to which intradialytic parenteral nutrition (IDPN) contributes to improve PEW status in HD patients intolerable to ONS remains unclear. Maintenance PEW HD patients being unable to tolerate ONS adverse effects, and having spontaneous energy and protein intake of ≥ 20 kcal/kg/day and ≥ 0.8 g/kg/day, respectively were randomly assigned 1:1 into IDPN and control groups. In IDPN group, most concentrated 3-in-1, fish-oil based parenteral nutrition was infused during HD for 3 months. The control group received intensive dietary counselling once weekly for 3 months. Both groups were then followed for additional 3 months after intervention. A total of 38 patients were randomized (mean age 67.6 years). After 3 months, serum albumin was significantly higher in the IDPN (n = 18) compared with control group (from 3.5 ± 0.3 to 3.8 ± 0.2 vs from 3.6 ± 0.3 to 3.5 ± 0.3 g/dL, respectively, p = 0.01). Spontaneous dietary intake (p = 0.04), body weight (p = 0.01), and malnutrition inflammation score (MIS, p = 0.01) were improved in the IDPN, but not in the control group. Muscle mass, strength, serum prealbumin, interleukin-6, high sensitivity-c reactive protein, and acylated ghrelin were not significantly different but leptin levels increased in the control group after 3 months (p = 0.03). At 6 months, serum albumin in the IDPN group was persistently higher than baseline (p = 0.04). Neither volume overload nor uncontrolled hyperglycemia was found throughout the study. In conclusion, a 3-month IDPN supplementation demonstrated a significant increase in serum albumin, body weight, spontaneous oral intake, and MIS; and appeared to be superior to continuing intensive dietary counselling among HD patients intolerable to ONS. The impacts of IDPN therapy on clinical outcomes may require larger scale with longer period of study.