Effect of a Home-Based Exercise Program on Indices of Physical Function and Quality of Life in Elderly Maintenance Hemodialysis Patients.

BACKGROUND: Patients on maintenance hemodialysis (MHD) exhibit muscle wasting and impaired physical function which can be reversed with regular exercise, but accessibility to exercise programs for this unique population is lacking. We assessed the efficacy of a home-based exercise program on a broad range of indices of physical function, quality of life (QoL), and cognitive decline in patients with MHD. DESIGN AND METHODS: Twenty-eight MHD patients, mean age 66 ± 7 years, were randomized to a 12-week home-based, case-managed aerobic and resistance exercise program or to usual care (13 exercise and 15 usual care). Comparisons were made for peak VO2, ventilatory inefficiency, 6-min walk test (6MWT), 1-min sit-to-stand (1STS), muscle strength, body composition, QoL, and cognitive measures. RESULTS: Peak VO2 improved significantly in the exercise group (p = 0.01 between groups); exercise time improved by 41 and 36% at the ventilatory threshold and peak exercise, respectively (p < 0.01 between groups), but there were no differences in ventilatory efficiency. Trends for improvements in 6MWT and 1STS in the exercise group were observed, but no differences were observed in strength or body composition. Among measures of QoL, general health determined by the SF-36 improved in the exercise group, but there were no differences between groups in cognitive function. CONCLUSIONS: MHD patients improved exercise capacity and some indices of QoL following a 12-week home-based exercise program. Home-based exercise is feasible for patients undergoing MHD and may help to obviate accessibility barriers to regular exercise.

Association of physical function and performance with peak VO2 in elderly patients with end stage kidney disease.

BACKGROUND: Physical function is impaired in end stage renal disease (ESRD). Various instruments have been used to assess the functional capabilities and health status of patients with ESRD, but it is not known which has the best association with peak VO2. AIMS: To assess the association between functional measures in ESRD. METHODS: Thirty nine elderly ESRD patients were evaluated with commonly used functional, health status, and quality of life measures, including maximal cardiopulmonary exercise testing (CPET), 6-min walk (6MWT), sit-to-stand test (STS), Veterans Specific Activity Questionnaire (VSAQ), upper and lower body strength, pulmonary function tests, and body composition determined by dual X-ray absorptiometry. The association between performance on these functional tools, clinical variables, and exercise test responses was assessed, and a non-exercise test multivariate model was developed to predict peak VO2. RESULTS: Peak VO2 was modestly related to VSAQ score (r = 0.59, p < 0.01), indices of upper and lower body strength (r = 0.45, p < 0.01 for both), and FEV1 (r = 0.51, p < 0.01). Functional and quality of life questionnaires were generally poorly related to one another and to peak VO2. In a multivariate model, 6MWT performance, forced expiratory volume in 1 s (FEV1), and VSAQ score were the best predictors of peak VO2, yielding a multiple R = 0.82, accounting for 67% of the variance in peak VO2. CONCLUSION: Exercise capacity can be reasonably estimated using non-exercise test variables in patients with ESRD, including a symptom questionnaire (VSAQ), 6MWT and FEV1. CLINICAL TRIAL INFORMATION: ClinicalTrials.gov identifier: NCT01990495. Registered Nov 21, 2013.

A randomized controlled trial of exercise to prevent muscle mass and functional loss in elderly hemodialysis patients: Rationale, study design, and baseline sample.

BACKGROUND: Elderly maintenance hemodialysis (MHD) patients exhibit muscle wasting and impaired physical function. This trial determines whether MHD patients benefit from a 12-week home-based exercise program, protein supplementation, or both. DESIGN: and Methods: This is a randomized, blinded controlled trial involving 60 elderly MHD patients with impaired exercise capacity and function. Patients are randomized into either a homebased exercise program or normal care over a 12-week period. Measures at baseline include peak VO2, strength and body composition as well as cognitive and disease-specific questionnaires. Muscle biopsies are obtained and analyzed for protein signaling, expression of IGF-1, androgen receptors, and myostatin. RESULTS: At baseline, patient characteristics in the exercise and normal care groups were similar by age, gender and anthropomorphic measures. Peak VO2 was impaired (14.7 ±â€¯3.3 ml/kg/min), representing 55 ±â€¯14% of the age-predicted value. Six-minute walk distance was 322 ±â€¯71 m, and the mean 1-min sit to stand test was 18 ±â€¯8 repetitions, representing 69 ±â€¯16% and 55 ±â€¯22% of the age-predicted values, respectively. Indices of muscle function, including upper and lower body and hand grip strength all indicate marked impairment. Quality of life (QoL) using the SF36, the Beeson cognitive test, and KDQOL all suggest marked impairments compared to age-expected reference values for non-MHD patients. CONCLUSIONS: Patients undergoing MHD exhibit markedly reduced physical function and QoL. Thus, there are potentially significant gains to be made through a program of aerobic and resistance exercise. We anticipate this trial will demonstrate that home-based exercise improves cardiopulmonary function, protein signaling and QoL, and increases muscle mass, strength, and body composition.

Effect of a Dialysis Access Coordinator on Preemptive Access Placement among Veterans: A Quality Improvement Initiative.

BACKGROUND AND OBJECTIVES: Preemptive placement of permanent dialysis access is recommended in order to reduce the morbidity associated with central venous catheters. We assessed the effect of a dialysis access coordinator on preemptive access placement in veterans who are at high risk for end-stage renal disease (ESRD). DESIGN, SETTING, PARTICIPANTS, AND MEASUREMENTS: Pre-post evaluation of a dialysis access coordinator in the nephrology clinics of the Veterans Affairs Palo Alto. The access coordinator streamlined access referrals, prioritized surgical waiting lists and addressed patient barriers. We compared the frequency of preemptive access referral, surgery, and use for dialysis during the intervention period, July 1, 2013 to May 31, 2016, to a pre-intervention period, January 1, 2011 to December 31, 2013, among all patients with a predicted 1-year risk for ESRD ≥20%. RESULTS: There were 156 patients in the historical cohort and 131 in the intervention cohort. The mean age was 69.9 ± 11.6 years and the mean estimated glomerular filtration rate was 14.5 ± 5.7 ml/min/1.73 m2. The intervention was associated with an 11.8% increase in access referral (p value = 0.03), and a 9.4% increase in completed access surgery (p value = 0.05). Increases in permanent access at the start of dialysis (15.2%), and functional permanent access at the start of dialysis (12.4%) did not reach statistical significance. Among patients who received access surgery, there was no significant difference in the prevalence of unused access. CONCLUSIONS: Implementation of an access coordinator was associated with a modest increase in preemptive access placement among patients who are at high risk for ESRD without increasing the prevalence of unused access.

Managing diabetic nephropathy: recent studies.

PURPOSE OF REVIEW: This review summarizes recent studies designed to identify improved treatments for diabetic nephropathy. RECENT FINDINGS: Recent data support the concept that angiotensin converting enzyme inhibitors and angiotensin II receptor blockers have similar renoprotective effects. Aggressive blockade of the renin-angiotensin system appears to have benefits beyond those achieved with conventional doses of single agents. Dual blockade using angiotensin converting enzyme inhibitors and angiotensin II receptor blockers is effective. Aldosterone receptor antagonists may potentiate the effect of these two classes of compounds. It remains unclear, however, whether maximum benefit can be obtained by the combination of angiotensin converting enzyme inhibitors and angiotensin II receptor blockers or aldosterone receptor antagonists as compared to larger doses of single agents. Not enough data are available currently to recommend thiazolidinedione hypoglycemic agents for renal protection. Trials are being conducted with several new classes of agents. SUMMARY: Evidence from short-term studies favors aggressive blockade of the renin-angiotensin system. Long-term studies, however, remain to be performed. A multifactorial approach that incorporates established interventions affords our best means to retard the progression of diabetic nephropathy.

Increasing dialysate flow and dialyzer mass transfer area coefficient to increase the clearance of protein-bound solutes.

Clinical hemodialysis systems achieve high single pass extraction of small solutes that are not bound to plasma proteins. But they clear protein-bound solutes much less effectively. This study examines the extent to which clearance of a protein-bound test solute is improved by increasing the dialyzer mass transfer area coefficient (KoA) and the dialysate flow rate (Qd). A reservoir containing test solutes and artificial plasma with albumin concentration approximately 4 g/dl was dialyzed with a standard clinical dialysate delivery system. The clearance of phenol red (ClPR) was compared with the clearances of urea and creatinine at a plasma flow rate (Qp) of 200 ml/min with varying values of KoA and Qd. ClPR increased from 11 +/- 2 ml/min to 23 +/- 2 ml/min when KoA for phenol red, KoAPR, was increased from 238 to 640 ml/min and Qd was increased from 286 +/- 6 ml/min to 734 +/- 9 ml/min. Increasing either KoAPR or Qd alone had lesser effects. Clearance values for phenol red were much lower than clearance values for the unbound solutes urea and creatinine, which ranged from 150 to 200 ml/min and were less affected by varying KoA and Qd. A mathematical model was developed to predict ClPR from values of Qp, Qd, the fraction of phenol red bound to albumin (94% +/- 1%) and KoAPR. The model accurately predicts the pattern of measured results and shows further that ClPR can be made to approach Qp only by very large increases in both KoAPR and Qd.