Functional Dependence and Mortality in the International Dialysis Outcomes and Practice Patterns Study (DOPPS)

Area of Science:

• Nephrology
• Gerontology
• Public Health

Background:

• Long-term dialysis patients face high mortality and hospitalization rates.
• Functional dependence is a known risk factor for disability, hospitalization, and mortality in nonrenal populations.
• Studies indicate a growing burden of functional dependence with worsening kidney function, potentially impacting dialysis patient outcomes.

Purpose of the Study:

• To investigate the association between functional status and all-cause mortality in hemodialysis patients.
• To determine if functional dependence is an independent predictor of mortality in this population.

Main Methods:

• Prospective cohort study of 7,226 hemodialysis patients across 12 countries (Dialysis Outcomes and Practice Patterns Study - DOPPS Phase 4).
• Functional status was assessed using self-reported ability to perform 13 activities of daily living, creating a functional status score.
• Cox regression analysis was employed to evaluate the relationship between functional status and mortality, adjusting for demographic and clinical factors.

Main Results:

• 36% of patients were functionally independent (score=13), while 14% exhibited high functional dependence (score < 8).
• Functionally independent patients were younger and had better health indicators.
• Adjusted analysis revealed a 2.37-fold increased mortality risk for patients with high functional dependence (score < 8) compared to functionally independent patients.

Conclusions:

• A significant burden of functional dependence exists across diverse dialysis patient groups and countries.
• Functional dependence was identified as a strong, consistent predictor of mortality, even after accounting for known risk factors.
• Findings underscore the importance of assessing and addressing functional status in hemodialysis patients to mitigate mortality risk.