Increased Physical Activity Linked to Reduced Mortality In Peritoneal Dialysis

New research in patients undergoing peritoneal dialysis (PD) suggests an incremental increase in physical activity level is associated with a 31% reduction in all-cause mortality risk.1

“Although the causality cannot be established, this retrospective cohort study demonstrated that higher physical activity levels and longer daily walking time were associated with favorable clinical outcomes in peritoneal dialysis patients,” wrote study investigator Chun-yan Su, a PhD student in the department of nephrology at Peking University Third Hospital.1

Previous studies have suggested an association between physical activity and the health status of patients undergoing PD, including mood disturbance, malnutrition, and sarcopenia progression. Physical activity has emerged as a potential predictor of health outcomes in PD, but few studies have explored this association.1,2

To address this gap in research, Su and colleagues conducted a retrospective observational cohort study assessing the association between physical activity behavior and mortality in participants with a median follow up of 4.40 years. The primary outcomes examined were all-cause mortality on PD, censored for loss to follow up, renal transplantation, transferred to hemodialysis due to technical failure, transferred to other dialysis centers, or end of study.1

They measured physical activity using the self-reported International Physical Activity Questionnaire (IPAQ). Based on participants' activity level, frequency, and duration, they were stratified into 3 groups: highly physically active, moderately physically active, and low physical activity.1

Investigators classified vigorous physical activity as heavy-intensity exercise for ≥ 3 days/ week with a cumulative energy expenditure >1500 metabolic equivalent minutes/week, daily walking and/or moderate-to-vigorous intensity activities > 3000 metabolic equivalent minutes/week. Participants at the moderate-level met the following criteria: moderate exercise ≥ 3 days/week (≥ 20 min/day), moderate physical activity or walking ≥ 5 days/week (≥ 30 min/day), or combined moderate/vigorous physical activity ≥ 5 days/week (>600 metabolic equivalent-minutes/week). Any participants not meeting these benchmarks were classified as having low-intensity levels.1

The study included 117 patients undergoing peritoneal dialysis for ≥ 3 months at the Peking University Third Hospital. The cohort distribution was: 31.6% low-intensity, 48.7% moderate-intensity, and 19.7% vigorous-intensity physical activity.1

Patients in the low-intensity physical activity group were significantly older, demonstrated significantly lower serum potassium and urea nitrogen levels, and exhibited significantly reduced hand grip strength as compared to patients with moderate-intensity physical activity and vigorous-intensity physical activity.1

Upon analysis, investigators found a correlation with patient survival and physical activity levels, with a statistically significant difference found among the 3 physical activity groups (log rank score 10.854, P = .002). Median survival time of patients with moderate-intensity physical activity (7.16 years, 95% Confidence Interval [CI], 6.02–8.29; log-rank score, 6.618; P = .011) and patients with vigorous-intensity physical activity (8.55 years, 95% CI, 6.97–10.13; log rank score 7.651; P = .005) were significantly longer than patients with low-intensity physical activity (4.88 years; 95% CI, 3.63–6.14), respectively.1

In univariate cox regression analysis, investigator identified several factors, including age (P <.001), ALB (P < .001), sodium groups (P = .027), dietary energy intake groups (P = .032), nutrition status assessed by subjective global assessment (SGA) (P < .001), hand grip strength (P = .003), walking time (minutes/day) (P = .026), metabolic equivalent (P = .005) and physical activity levels (P = .002) as predictors of survival.1

After adjusting for confounding factors, the increased level of physical activity (adjusted hazard ratio [aHR], 0.68, 95% CI, 0.46–0.98, P = .040) and daily walking time per 30 min/day (aHR 0.86, 95% CI 0.75-1.00, P = .045) were independently associated with reduced mortality in peritoneal dialysis patients.1

“Given that limited mobility is associated with poorer outcomes, these findings may suggest that the utility of a holistic patient-centered care approach for these patients care planning and prognostic discussions,” concluded investigators.1

References

1. Wang J, Nie J, Tang W, Su C. Physical activity levels and mortality in peritoneal dialysis patients. BMC Nephrology. 2025;26(1):694-694. doi:https://doi.org/10.1186/s12882-025-04607-0

2. Tarca B, Shilpanjali Jesudason, Bennett PN, Wycherley TP, Ferrar KE. Characteristics and Frequency of Physical Activity and Exercise-Related Side-Effects in People Receiving Peritoneal Dialysis. Journal of Renal Nutrition. 2023;34(4):359-367. doi:https://doi.org/10.1053/j.jrn.2023.12.003