Low physical activity and risk of cardiovascular and all-cause mortality in renal transplant recipients

Abstract

Background and objectives: Low physical activity (PA) is a risk factor for mortality in the general population. This is largely unexplored in renal transplant recipients (RTRs). We studied whether PA is associated with cardiovascular and all-cause mortality in a prospective cohort of RTR.

Design, setting, participants, & measurements: Between 2001 and 2003, 540 RTRs were studied (age, 51 ± 12 years; 54% male). PA was assessed using validated questionnaires (Tecumseh Occupational Activity Questionnaire and the Minnesota Leisure Time Physical Activity Questionnaire). Cardiovascular and all-cause mortality were recorded until August 2007.

Results: Independent of age, PA was inversely associated with metabolic syndrome, history of cardiovascular disease, fasting insulin, and triglyceride concentration, and positively associated with kidney function and 24-hour urinary creatinine excretion (i.e., muscle mass). During follow-up for 5.3 years (range, 4.7 to 5.7 years), 81 RTRs died, with 37 cardiovascular deaths. Cardiovascular mortality was 11.7, 7.2, and 1.7%, respectively, according to gender-stratified tertiles of PA (P=0.001). All-cause mortality was 24.4, 15.0, and 5.6% according to these tertiles (P<0.001). In Cox regression analyses, adjustment for potential confounders including history of cardiovascular disease, muscle mass, and traditional risk factors for cardiovascular disease did not materially change these associations.

Conclusions: Low PA is strongly associated with increased risk for cardiovascular and all-cause mortality in RTRs. Intervention studies are necessary to investigate whether PA improves long-term survival after renal transplantation.

© 2011 by the American Society of Nephrology

Figures

Figure 1.

(A) Kaplan-Meier curves of cardiovascular mortality according to gender-stratified tertiles of PA. *Adjusted for age (P < 0.001). (B) Kaplan-Meier curves of mortality according to gender-stratified tertiles of PA. *Adjusted for age (P < 0.001).