Kirsten L. Johansen

Significance of Frailty among Dialysis Patients

The construct of frailty has been associated with adverse outcomes among elderly individuals, but the prevalence and significance of frailty among patients with end-stage renal disease have not been established. The aim of the current study was to determine the prevalence and predictors of frailty

Effects of Resistance Exercise Training and Nandrolone Decanoate on Body Composition and Muscle Function among Patients Who Receive Hemodialysis: A Randomized, Controlled Trial

Patients who are on hemodialysis commonly experience muscle wasting and weakness, which have a negative effect on physical functioning and quality of life. The objective of this study was to determine whether anabolic steroid administration and resistance exercise training induce anabolic effects among patients who receive maintenance hemodialysis. A randomized 2 x 2 factorial trial of anabolic steroid administration and resistance exercise training was conducted in 79 patients who were receiving maintenance hemodialysis at University of California, San Francisco-affiliated dialysis units. Interventions included double-blinded weekly nandrolone decanoate (100 mg for women; 200 mg for men) or placebo injections and lower extremity resistance exercise training for 12 wk during hemodialysis sessions three times per week using ankle weights. Primary outcomes included change in lean body mass (LBM) measured by dual-energy x-ray absorptiometry, quadriceps muscle cross-sectional area measured by magnetic resonance imaging, and knee extensor muscle strength. Secondary outcomes included changes in physical performance, self-reported physical functioning, and physical activity. Sixty-eight patients completed the study. Patients who received nandrolone decanoate increased their LBM by 3.1 +/- 2.2 kg (P < 0.0001). Exercise did not result in a significant increase in LBM. Quadriceps muscle cross-sectional area increased in patients who were assigned to exercise (P = 0.01) and to nandrolone (P < 0.0001) in an additive manner. Patients who exercised increased their strength in a training-specific fashion, and exercise was associated with an improvement in self-reported physical functioning (P = 0.04 compared with nonexercising groups). Nandrolone decanoate and resistance exercise produced anabolic effects among patients who were on hemodialysis. Further studies are needed to determine whether these interventions improve survival.

Exercise in the End-Stage Renal Disease Population

Many of the known benefits of exercise in the general population are of particular relevance to the ESRD population. In addition, the poor physical functioning that is experienced by patients who are on dialysis is potentially addressable through exercise interventions. The study of exercise in the ESRD population dates back almost 30 yr, and numerous interventions, including aerobic training, resistance exercise training, and combined training programs, have reported beneficial effects. Recently, interventions during hemodialysis sessions have become more popular and have been shown to be safe. The risks of exercise in this population have not been rigorously studied, but there have been no reports of serious injury as a result of participation in an exercise training program. It is time that we incorporate exercise into the routine care of patients who are on dialysis, but identification of an optimal training regimen or regimens, according to patient characteristics or needs, is still needed to facilitate implementation of exercise programs.

Survival and hospitalization among patients using nocturnal and short daily compared to conventional hemodialysis: a USRDS study

We estimated the survival and hospitalization among frequent hemodialysis users in comparison to those patients undergoing thrice-weekly conventional hemodialysis. All patients had similar characteristics and medical histories. In this cohort study of frequent hemodialysis users and propensity score-matched controls, the collaborating clinicians identified 94 patients who used nocturnal hermodialysis (NHD) and 43 patients who used short-duration daily hemodialysis (SDHD) for a minimum of 60 days. Ten propensity score-matched control patients for each NHD and SDHD patient were identified from the United States Renal Data System database. Primary outcomes were risk for all-cause mortality and risk for the composite outcome of mortality or major morbid event (acute myocardial infarction or stroke) estimated using Cox proportional hazards models. Risks for all-cause, cardiovascular-related, infection-related, and vascular access-related hospital admissions were also studied. Nocturnal hemodialysis was associated with significant reductions in mortality risk and risk for mortality or major morbid event when compared to conventional hemodialysis. There was a reduced but non-significant risk of death for patients using SDHD compared to controls. All-cause and specific hospitalizations did not differ significantly between NHD and SDHD patients and their matched control cohorts. Our study suggests that NHD may improve patient survival.

Time- and exercise-dependent gene regulation in human skeletal muscle.

BackgroundSkeletal muscle remodeling is a critical component of an organisms response to environmental changes. Exercise causes structural changes in muscle and can induce phase shifts in circadian rhythms, fluctuations in physiology and behavior with a period of around 24 hours that are maintained by a core clock mechanism. Both exercise-induced remodeling and circadian rhythms rely on the transcriptional regulation of key genes.ResultsWe used DNA microarrays to determine the effects of resistance exercise (RE) on gene regulation in biopsy samples of human quadriceps muscle obtained 6 and 18 hours after an acute bout of isotonic exercise with one leg. We also profiled diurnal gene regulation at the same time points (2000 and 0800 hours) in the non-exercised leg. Comparison of our results with published circadian gene profiles in mice identified 44 putative genes that were regulated in a circadian fashion. We then used quantitative PCR to validate the circadian expression of selected gene orthologs in mouse skeletal muscle.ConclusionsThe coordinated regulation of the circadian clock genes Cry1, Per2, and Bmal1 6 hours after RE and diurnal genes 18 hours after RE in the exercised leg suggest that RE may directly modulate circadian rhythms in human skeletal muscle.

Exercise in Individuals With CKD

There are few studies evaluating exercise in the nondialysis chronic kidney disease (CKD) population. This review covers the rationale for exercise in patients with CKD not requiring dialysis and the effects of exercise training on physical functioning, progression of kidney disease, and cardiovascular risk factors. In addition, we address the issue of the risk of exercise and make recommendations for implementation of exercise in this population. Evidence from uncontrolled studies and small randomized controlled trials shows that exercise training results in improved physical performance and functioning in patients with CKD. In addition, although there are no studies examining cardiovascular outcomes, several studies suggest that cardiovascular risk factors such as hypertension, inflammation, and oxidative stress may be improved with exercise training in this population. Although the current literature does not allow for definitive conclusions about whether exercise training slows the progression of kidney disease, no study has reported worsening of kidney function as a result of exercise training. In the absence of guidelines specific to the CKD population, recent guidelines developed for older individuals and patients with chronic disease should be applied to the CKD population. In sum, exercise appears to be safe in this patient population if begun at moderate intensity and increased gradually. The evidence suggests that the risk of remaining inactive is higher. Patients should be advised to increase their physical activity when possible and be referred to physical therapy or cardiac rehabilitation programs when appropriate.

Frailty, Dialysis Initiation, and Mortality in End-Stage Renal Disease

BACKGROUND In light of the recent trend toward earlier dialysis initiation and its association with mortality among patients with end-stage renal disease, we hypothesized that frailty is associated with higher estimated glomerular filtration rate (eGFR) at dialysis start and may confound the relation between earlier dialysis initiation and mortality. METHODS We examined frailty among participants of the Comprehensive Dialysis Study (CDS), a special study of the US Renal Data System, which enrolled incident patients from September 1, 2005, through June 1, 2007. Patients were followed for vital status through September 30, 2009, and for time to first hospitalization through December 31, 2008. We used multivariate logistic regression to model the association of frailty with eGFR at dialysis start and proportional hazards regression to assess the outcomes of death or hospitalization. RESULTS Among 1576 CDS participants included, the prevalence of frailty was 73%. In multivariate analysis, higher eGFR at dialysis initiation was associated with higher odds of frailty (odds ratio [OR], 1.44 [95% CI, 1.23-1.68] per 5 mL/min/1.73 m(2); P < .001). Frailty was independently associated with mortality (hazard ratio [HR], 1.57 [95% CI, 1.25-1.97]; P < .001) and time to first hospitalization (HR, 1.26 [95% CI, 1.09-1.45]; P < .001). While higher eGFR at dialysis initiation was associated with mortality (HR, 1.12 [95% CI, 1.02-1.23] per 5 mL/min/1.73 m(2); P = .02), the association was no longer statistically significant after frailty was accounted for (HR, 1.08 [95% CI, 0.98-1.19] per 5 mL/min/1.73 m(2); P = .11). CONCLUSIONS Frailty is extremely common among patients starting dialysis in the United States and is associated with higher eGFR at dialysis initiation. Recognition of signs and symptoms of frailty by clinicians may prompt earlier initiation of dialysis and may explain, at least in part, the well-described association between eGFR at dialysis initiation and mortality.

Physical Functioning and Exercise Capacity in Patient on Dialysis

Patients on dialysis have extremely limited exercise capacity, and poor physical functioning has been linked to low quality of life and high mortality in this population. The reason for the debility of patients on dialysis is far from clear despite years of study. The anemia of chronic renal disease is clearly a contributing factor, but uremic myopathy and resulting decreased muscle oxygen utilization have a significant impact on the physical functioning of patients on dialysis as well. Although it is likely that factors related to uremia adversely affect muscle function, some of the abnormalities demonstrated in uremic muscle are consistent with disuse atrophy. The clear contribution of anemia and the possible role of limited physical activity have led to studies of the effects of erythropoietin and aerobic exercise training on exercise capacity in end-stage renal disease patients. Both of these interventions result in increased exercise capacity. Thus vigorous treatment of anemia and uremia and encouragement of physical activity are important interventions to maximize the physical functioning of patients on dialysis. In addition, more studies are needed to clarify the causes of debility in this population and the impact of interventions on physical functioning, quality of life, and mortality.

Exercise and chronic kidney disease: current recommendations.

AbstractPatients with chronic kidney disease (CKD) are inactive and have reduced physical functioning and performance. Aerobic exercise interventions have been shown to increase maximal oxygen consumption in selected patients. In addition, preliminary evidence, although mixed, suggests that aerobic exercise training can improve blood pressure control, lipid profiles and mental health in this population. A few larger studies are now available showing that aerobic training can also improve physical functioning and performance. The impact on survival or hospitalisation has not been determined. Resistance exercise training, although less studied, appears to increase muscle strength and size and may also improve functioning. There have been several reports of successful combined exercise interventions, but the designs have not allowed evaluation of the relative benefits of aerobic and resistance training on physical functioning. Despite the evidence that exercise is safe and beneficial in patients with CKD, dialysis patients remain inactive, and exercise assessment, counselling and training is not widely offered to patients with CKD.Studies of the barriers to patient participation in exercise and to provider assessment and recommendations are needed so that more widely generalisable interventions can be developed. However, in the interim, patients should be encouraged to participate in moderate physical activity to meet the US Surgeon General’s recommendations. Patients who are weak can benefit from strength-training interventions. Resistance and aerobic exercise programmes should be initiated at relatively low intensity in patients with CKD and progressed as slowly as tolerated in order to avoid injury and discontinuation of exercise. For patients on haemodialysis, incorporation of exercise into the dialysis session may increase patient participation and tolerance of exercise.

Influence of Race on Kidney Transplant Outcomes within and outside the Department of Veterans Affairs

Inferior outcomes after kidney transplantation among African Americans are poorly understood. It was hypothesized that unequal access to medical care among transplant recipients might contribute to worse posttransplantation outcomes among African Americans and that racial disparities in kidney transplant outcomes would be less pronounced among patients who receive health care within versus outside the Department of Veterans Affairs (VA), because eligible veterans who receive care within the VA are entitled to receive universal access to care, including coverage of prescription drugs. A study cohort of 79,361 patients who were undergoing their first kidney transplant in the United States between October 1, 1991, and October 31, 2000, was assembled, with follow-up data on graft survival obtained through October 31, 2001. After multivariable proportional hazards adjustment for a wide range of recipient and donor characteristics, African-American patients were at increased risk for graft failure compared with non-African-American patients (relative risk [RR] 1.31; 95% confidence interval [CI] 1.26 to 1.36). African-American race was associated with a similarly increased risk for graft failure among patients who were VA users (RR 1.31; 95% CI 1.11 to 1.54) and non-VA users (RR 1.31; 95% CI 1.26 to 1.36). In conclusion, racial disparities in kidney transplant outcomes seem to persist even in a universal access-to-care system such as the VA. Reasons for worse outcomes among African Americans require further investigation.