Body Composition and Its Clinical Outcome in Maintenance Hemodialysis Patients

Previous epidemiological cohorts demonstrated that higher body mass index (BMI) was associated with greater survival in patients treated by hemodialysis. Although BMI is a simple measure of adiposity in general population, it may be an inaccurate indicator of nutritional status, particularly among dialysis patients given that it does not differentiate between muscle mass and fat as well as body fat distribution. This problem might be aggravated in end-stage renal disease patients because of wasting or edema. In addition, individuals with higher BMI usually have both higher muscle and fat mass than those with lower BMI. Therefore, more sophisticated tool of body composition analysis is needed to address the query of which component is associated with mortality outcome among patients receiving hemodialysis. We summarized the current state of body composition, including lean and fat tissue evaluated by bioelectrical impedance analysis, dual X-ray absorptiometry, computerized tomography, or magnetic resonance imaging, and its association with clinical outcomes among hemodialysis patients. The studies using anthropometry for the estimation of muscle mass, either mid-arm muscle circumference as a proxy of muscle mass or skinfold thickness and waist circumference as a surrogate of body fat and visceral fat, respectively, were all included in this review

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

BackgroundA 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.MethodsSixty 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.ResultsThe 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.ConclusionA 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 registrationClinicalTrials.gov (NCT02623348). 02 December 2015

Consequences of CKD on Functioning

Chronic kidney disease (CKD) is highly prevalent in the United States and throughout the world,(1) with approximately 13% of adults affected.(2) In addition, according to recent estimates, almost half of patients with CKD stages 3 to 5 are 70 years of age and older.(2) In the United States, the number of prevalent end-stage renal disease cases continues to increase in patients older than age 65. In light of the demographic characteristics of patients with CKD and ESRD, there has been considerable focus on associations between CKD and cardiovascular outcomes.(3) Until recently, less attention had been paid to other consequences of CKD in general and among older individuals with CKD in particular, but there is now solid evidence linking CKD with impairments of physical function, cognitive function, and emotional function and quality of life. This review summarizes available literature on these topics, focusing specifically on physical functioning and frailty, cognitive function, emotional health, including depression and anxiety, and health-related quality of life

Higher Physical Activity Is Associated With Less Fatigue and Insomnia Among Patients on Hemodialysis

Introduction: Patients on hemodialysis experience a heavy burden of symptoms that may be related to the low levels of physical activity reported in this population. We hypothesized that physical activity would be inversely related to symptom severity and that depression might mediate this association. Methods: We designed a cross-sectional study of 48 patients receiving hemodialysis at 3 San Francisco dialysis clinics. Physical activity was measured using pedometers and recorded within 1 week of symptom assessment. Symptoms were assessed using total symptom burden and severity on the Dialysis Symptom Index (DSI; burden 0–29, severity 0–145), individual symptoms on the DSI (0–5), Kidney Disease Quality of Life Vitality scores, (0–100), and the Center for Epidemiologic Study-Depression (0–60). Results: Median daily step count was 2631 (25th, 75th percentile 1125, 5278). Seventy-three percent of patients reported fatigue. After adjustment for age, sex, diabetes, and serum albumin, physical activity was associated with 0.2 points lower fatigue severity per 1000 steps per day (95% confidence interval [CI] −0.3 to 0.0), P = 0.04. Physical activity was also associated with higher Vitality score (2.36 points per 1000 steps; 95% CI 0.07–4.65) and lower insomnia scores (−0.1 points per 1000 steps; 95% CI −0.3 to 0.0], P < 0.05) in our adjusted models. Physical activity was not associated with other symptoms. Conclusion: Because the study was cross-sectional, we cannot determine whether physical activity lowers fatigue and insomnia or whether less insomnia and fatigue increase physical activity. However, interventions to increase physical activity should be considered alongside current strategies as a possible approach to managing fatigue and insomnia. Keywords: dialysis, fatigue, physical activity, QoL, symptom

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.MethodsWe recruited patients receiving dialysis for ≥3 months from 3 dialysis facilities in San Francisco. Spontaneous walking activity was measured by pedometers over 7&nbsp;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&nbsp;minutes to administer. The LoPAQ also asks about time spent in sitting activities over 1&nbsp;week. Spearman correlation was used to determine whether the LoPAQ results correlate with step counts.ResultsSixty dialysis patients (HD&nbsp;=&nbsp;48, PD&nbsp;=&nbsp;12) completed the LoPAQ and wore a pedometer for 1&nbsp;week. Mean age was 58.0&nbsp;±&nbsp;12.7&nbsp;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&nbsp;=&nbsp;0.53, P&nbsp;&lt;&nbsp;.001). In addition, the overall activity reported on the LoPAQ correlated with weekly pedometer readings (rho&nbsp;=&nbsp;0.35, P&nbsp;=&nbsp;.01) and did not differ between HD and PD patients.ConclusionsThe 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

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

Rationale &amp; objectivePatients 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 designPilot randomized controlled trial.Setting &amp; participants60 dialysis patients from San Francisco dialysis clinics.InterventionParticipants were randomly assigned 1:1 to receiving pedometers with weekly step goals or usual care for 3 months.OutcomesThe 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%.Results49% 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&lt;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&nbsp;= 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.LimitationsThe Northern California study setting may limit generalizability. Walking does not capture the full spectrum of physical activity.ConclusionsA 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.FundingSupported 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 registrationRegistered at ClinicalTrials.gov with study identifier NCT02623348

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

BackgroundA 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.MethodsSixty 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.ResultsThe 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&nbsp;&lt; 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.ConclusionA 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 registrationClinicalTrials.gov (NCT02623348). 02 December 2015

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

Abstract 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  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