This study suggests that long-term exercise training improves physical impairment, arterial stiffness and health-related quality of life in patients with predialysis CKD. A larger randomized trial is required to examine the impact of exercise on markers of cardiovascular risk and quality of life in predialysis CKD patients.

Abstract. Cardiovascular disease remains the primary cause of mortality in patients who are maintained on hemodialysis. Arterial stiffness and insulin resistance are independent risk factors for cardiovascular mortality in this population. In healthy individuals, higher physical conditioning is associated with reduced arterial stiffness. Exercise reduces insulin resistance and glucose intolerance in sedentary, overweight individuals and diabetic patients. The purpose of this study was to determine the impact of an exercise program on arterial stiffness and insulin resistance in a group of patients on hemodialysis. The effect of exercise training on arterial stiffness and insulin resistance in 11 patients who were on chronic hemodialysis was evaluated. Exercise classes of 1-h duration were conducted twice weekly for 3 mo. Arterial stiffness was assessed using the radial artery pressure waveform analysis. Aerobic exercise improved arterial stiffness from 17 Ϯ 3 u at baseline to 12.2 Ϯ 3 u at the end of the intervention (P ϭ 0.01). After 1 mo of detraining, arterial stiffness reverted to preexercise levels (17.3 Ϯ 3 u). Pulse pressure paralleled arterial stiffness changes, and the correlation between them was statistically significant (r ϭ 0.725, P ϭ 0.012). Insulin resistance was calculated using the homeostatic model assessment formula. Exercise at the intensity and duration used in our study had no impact on insulin resistance (P ϭ 0.38). These findings suggest that 3 mo of aerobic exercise training improves arterial stiffness, an independent risk factor for cardiovascular mortality in patients who are on hemodialysis, and has no impact on insulin resistance. The beneficial effect on arterial stiffness dissipates within 1 mo of detraining. To obtain therapeutic benefits, an exercise program for patients who are maintained on hemodialysis should be designed to promote regular long term exercise, Ͼ3 h/wk. Despite significant advances in the technique and quality of their treatment, patients who are on hemodialysis (HD) continue to display high morbidity and mortality. Cardiovascular (CV) events account for up to 50% of deaths in this population (1). Recent studies have demonstrated that both arterial stiffness and insulin resistance are independent risk factors for CV mortality in patients with ESRD (2,3).In patients who are on HD, arterial stiffness is associated with increased left ventricular afterload, left ventricular hypertrophy, decreased subendocardial perfusion, and increased mechanical fatigue of the arteries. Moreover, uremic patients are universally insulin resistant. Insulin resistance may be involved in the pathogenesis of atherosclerosis, hypertension, and dyslipidemia.Rehabilitation programs, focusing on exercise, benefited patients after myocardial infarction, bypass surgery, chronic lung disease, rheumatologic disorders, strokes, and other neurologic conditions. Central effects of exercise training in patients who are on HD include improved left ventricular function, a beneficial effect on corona...

SummaryBackground and objectives Exercise capacity is impaired at a younger age in CKD patients than in the general population. This study examined the reliability of the Duke Activity Status Index (DASI) questionnaire as a measure of exercise capacity in medically stable adults with stage 3-4 CKD (estimated GFR [eGFR], 15-59 ml/min per 1.73 m 2 ).Design, setting, participants, & measurements Peak oxygen uptake ( _ VO 2 peak), estimated from DASI responses and cardiopulmonary exercise test measurements, was obtained at baseline and 6 months in a derivation sample (n=23) and once in a validation sample (n=20). Bland-Altman analysis and linear mixed models were used to estimate bias, concordance correlation coefficients, and intraclass correlation coefficients as the proportion of the variance due to participant (intertest reliability) and method (test-retest reliability).Results The two samples were homogeneous with respect to age (mean 60614 years), eGFR (35.5615 ml/min per 1.73 m 2 ), male sex (53%), and diabetes (56%). Mean measured _ VO 2 peak was 16.564 ml/kg per min. The DASI questionnaire overestimated _ VO 2 peak by 4.3 ml/kg per min. Intertest reliability was 53% when eGFR was $35 ml/min per 1.73 m 2 (median) and 60% when eGFR was ,35 ml/min per 1.73 m 2 (P,0.01). Test-retest reliability was 81% when eGFR was ,35 ml/min per 1.73 m 2 and 71% when eGFR was $35 ml/min per 1.73 m 2 (P,0.01).Conclusions The DASI questionnaire may be a reliable measure of exercise capacity in CKD patients, especially when eGFR is ,35 ml/min per 1.73 m 2 . Larger prospective studies are needed to determine its prognostic value.

No abstract