Characteristics and Outcomes of Patients With Systemic Sclerosis (Scleroderma) Requiring Renal Replacement Therapy in Europe: Results From the ERA-EDTA Registry
Abstract
Rationale & Objective: Data for outcomes of patients with end-stage renal disease (ESRD) secondary to systemic sclerosis (scleroderma) requiring renal replacement therapy (RRT) are limited. We examined the incidence and prevalence of ESRD due to scleroderma in Europe and the outcomes among these patients following initiation of RRT.
Study Design: Registry study of incidence and prevalence and a matched cohort study of clinical outcomes. Setting & Participants: Patients represented in any of 19 renal registries that provided data to the European Renal Association-European Dialysis and Transplant Association (ERA-EDTA) Registry between 2002 and 2013.
Predictor: Scleroderma as the identified cause of ESRD. Outcomes: Incidence and prevalence of ESRD from scleroderma.
Recovery from RRT dependence, patient survival after ESRD, and graft survival after kidney transplantation. Analytical Approach: Incidence and prevalence were calculated using population data from the European Union and standardized to population characteristics in 2005.
Patient and graft survival were compared with 2 age- and sex-matched control groups without scleroderma: (1) diabetes mellitus as the cause of ESRD and (2) conditions other than diabetes mellitus as the cause of ESRD. Survival analyses were performed using Kaplan-Meier analysis and Cox regression.
Results: 342 patients with scleroderma (0.14% of all incident RRT patients) were included. Between 2002 and 2013, the range of adjusted annual incidence and prevalence rates of RRT for ESRD due to scleroderma were 0.11 to 0.26 and 0.73 to 0.95 per million population, respectively.
Recovery of independent kidney function was greatest in the scleroderma group (7.6% vs 0.7% in diabetes mellitus and 2.0% in other primary kidney diseases control group patients, both P < 0.001), though time required to achieve recovery was longer. The 5-year survival probability from day 91 of RRT among patients with scleroderma was 38.9% (95% CI, 32.0%-45.8%), whereas 5-year posttransplantation patient survival and 5-year allograft survival were 88.2% (95% CI, 75.3%-94.6%) and 72.4% (95% CI, 55.0%-84.0%), respectively.
Adjusted mortality from day 91 on RRT was higher among patients with scleroderma than observed in both control groups (HRs of 1.25 [95% CI, 1.05-1.48] and 2.00 [95% CI, 1.69-2.39]). In contrast, patient and graft survival after kidney transplantation did not differ between patients with scleroderma and control groups.
Limitations: No data for extrarenal manifestations, treatment, or recurrence. Conclusions: Survival of patients with scleroderma who receive dialysis for more than 90 days was worse than for those with other causes of ESRD.
Patient survival after transplantation was similar to that observed among patients with ESRD due to other conditions. Patients with scleroderma had a higher rate of recovery from RRT dependence than controls.