Healthy lifestyle may help prolong lives of individuals with chronic kidney disease

Certain lifestyle factors—such as not smoking, getting regular physical activity, and avoiding a low body weight—may help prolong the lives of individuals with chronic kidney disease (CKD), according to a study appearing in an upcoming issue of the Clinical Journal of the American Society of Nephrology (CJASN).

More than 26 million individuals in the United States have CKD. In the general population, a healthy lifestyle is linked with a lower risk of dying prematurely, but little is known about such a link in individuals with CKD, who are at higher risk for developing heart problems and dying from heart disease.

To investigate, Ana Ricardo, MD (University of Illinois Hospital and Health Sciences System) and her colleagues assessed the association of four lifestyle factors (diet, physical activity, body mass index (BMI), and smoking) with death among 2,288 participants with CKD in the Third National Health and Nutrition Examination Survey.

After an average follow-up of 13 years, 1,319 deaths occurred. Among the major findings:
•Compared with individuals with the lowest healthy lifestyle score, participants with the highest score (nonsmokers who exercised regularly, had a healthy diet, and kept a BMI above 22 kg/m2) were 53% less likely to die from any cause.
•Individuals with a BMI of 18.5 to <22 had a 30% increased mortality rate compared with those with a BMI of 22 to <25 kg/m2. (Normal BMI is 18.5 to 24.9 kg/m2.)
•There was a 46% decreased mortality with never vs current smoking, and 20% decreased mortality with regular vs no physical activity.
•Diet was not significantly associated with mortality.

"Examination of individual components of the healthy lifestyle score, with adjustment for other components, suggested that the greatest reduction in all-cause mortality was related to nonsmoking," said Dr. Ricardo.

The findings reinforce the importance of smoking abstinence counseling in CKD patients and point to the possible benefits of regular physical activity and maintaining a healthy weight. The authors noted that additional work is needed to confirm the results and to investigate what the optimal diet and BMI are in CKD patients.

In an accompanying editorial, Srinivasan Beddhu, MD and Jo Abraham, MD (VA Healthcare System and University of Utah School of Medicine) stated that this study should stimulate interest in lifestyle interventions in CKD and dialysis patients, although because it was observational in nature, it cannot be said for certain that a healthier lifestyle caused prolonged survival. However, when considering the findings of this and other studies, "it seems clear that a healthy lifestyle of not smoking, increased physical activity and a diet high in fruits and vegetables and low in concentrated sweets is warranted," they wrote. "Interventions that increase muscle mass and decrease fat mass are likely to be beneficial in the CKD and dialysis population," they added.