Walking May Lower Risk for Death or Need for Dialysis in CKD

Veronica Hackethal, MD

May 21, 2014

Walking could significantly decrease mortality and the need for dialysis in individuals with chronic kidney disease (CKD), according to a study published online May 15 in the Clinical Journal of the American Society of Nephrology.

"Walking is the most popular exercise in [patients with CKD] and is associated with lower risk of overall mortality and lower risk of renal replacement therapy," write I-Ru Chen, MD, from the Kidney Institute and Division of Nephrology, Department of Internal Medicine, China Medical University Hospital, Taichung, Taiwan, and colleagues. "The benefit of walking is independent of patients' age, renal function, and comorbidity."

Past studies have associated walking with improvements in cardiorespiratory and physical fitness, blood pressure control, a malnutrition-inflammation complex syndrome common in chronic disease, and overall better quality of life in patients with CKD, the authors note.

They enrolled all patients with stage 3 to 5 CKD in the China Medical University Hospital, Taiwan, outpatient CKD program from June 2003 to May 2013. The institution's internal review board waived the need for informed consent. Participants self-reported the type, frequency, and duration of physical activity during the 3 months before enrollment, with families or caregivers being asked to provide confirmation.

Overall, 6363 patients enrolled in the study, with a mean follow-up time of 1.3 years; 552 patients (8.7%) were lost to follow-up.

Participants reported walking as their most common exercise (n = 1341; 21.1%). No significant differences existed between walking and nonwalking groups concerning hematopoietin treatment, body mass index, renal function, and the prevalence of comorbid conditions (diabetes, chronic glomerulonephritis, hypertension, coronary artery disease, stroke, or cancer within the last 5 years).

However, the analysis suggests that walkers had 33% lower likelihood of mortality and 21% lower likelihood of needing renal replacement therapy (adjusted subdistribution hazard ratio, 0.67 [95% confidence interval, 0.53 - 0.84; P < .001] and 0.79 [95% confidence interval, 0.73 - 0.85; P < .001], respectively).

Moreover, the benefits of walking seemed to accrue with increased time spent walking. Compared with nonwalkers, participants who walked 1 to 2, 3 to 4, 5 to 6, and 7 or more times per week had an overall reduction in the risk for death of 17%, 28%, 58%, and 59%, respectively. Likewise, participants who walked 1 to 2, 3 to 4, 5 to 6, and 7 or more times per week had a 19%, 27%, 43%, and 44% lower likelihood for renal replacement therapy.

After adjusting for age, renal function, and comorbidities, walkers had significantly lower incidence of mortality compared with nonwalkers.

Limitations included the inability to assess the influence of caregivers and physicians on frequency and duration of exercise, as well as overall outcomes. Other limitations included lack of information on the continuation of exercise during follow-up or on factors that could affect participants' ability to walk, such as claudication or need for assistance.

"We have shown that CKD patients with comorbidities were able to walk if they wanted to, and that walking for exercise is associated with improved patient survival and a lower risk of dialysis," coauthor Che-Yi Chou, MD, PhD, said in a journal press release, "A minimal amount of walking — just once a week for less than 30 minutes — appears to be beneficial, but more frequent and longer walking may provide a more beneficial effect."

The authors have disclosed no relevant financial relationships.

Clin J Am Soc Nephrol. Published online May 15, 2014. Abstract


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.