ABSTRACT
RATIONALE & OBJECTIVE: Prolonged end-stage kidney disease (ESKD) is a risk factor for frailty and the number of patients in Japan receiving maintenance dialysis for more than 20 years is large and growing. This study aimed to characterize the association of dialysis vintage and frailty among patients receiving dialysis in Japan. STUDY DESIGN: Cross-sectional study. SETTING & PARTICIPANTS: Patients with ESKD aged over 50 years of age who received maintenance dialysis in 2018 as represented in the JSDT Renal Data Registry database (n=227,136). EXPOSURES: Dialysis vintage categorized as: 0-<5 years, 5-<10 years, 10-<20 years, 20-<30 years, and over 30 years. OUTCOMES: The frailty and bedridden status were defined as graded ≥2 and graded 4, respectively, according to the Eastern Cooperative Oncology Group Performance Status scale. ANALYTICAL APPROACH: Poisson regression models with robust error variance adjusted for potential covariates were used to estimate the adjusted prevalence ratios (aPRs) for frailty and bedridden status. Clinical characteristics of patients undergoing dialysis for ≥ 30 years were also described. RESULTS: Among the study cohort, 5510 patients (2.4%) had been undergoing dialysis for 30 years or more. The prevalence of frailty in the group with over 30 years of dialysis history was 36.2%, while the rate of being bedridden was 6.4%. Compared to <5 years, dialysis vintages of 5-<10 years, 10-<20 years, 20-<30 years, and over 30 years were associated with frailty (aPRs [95% confidence intervals]: 1.06 [1.05-1.08], 1.10 [1.08-1.11], 1.14 [1.10-1.17], and 1.67 [1.60-1.73]), respectively. Compared to <5 years, dialysis vintages of 5-<10 years, 10-<20 years, 20-<30 years, and over 30 years were associated with being bedridden (aPRs [95% confidence intervals]: 1.17 [1.13-1.22], 1.26 [1.20-1.31], 1.17 [1.08-1.26], and 1.66 [1.49-1.86], respectively. LIMITATIONS: Patients receiving short-term dialysis may have more unmeasured comorbidities compared to patients receiving long-term dialysis. CONCLUSIONS: Long-term dialysis therapy, particularly exceeding 30 years, is associated with deterioration of physical function and frailty.
