Variation in the Level of eGFR at Dialysis Initiation across Dialysis Facilities and Geographic Regions

Abstract

Background and objectives The relative influence of facilities and regions on the timing of dialysis initiation remains unknown. The purpose of the study is to determine the variation in eGFR at dialysis initiation across dialysis facilities and geographic regions in Canada after accounting for patient-level factors (case mix).Design, setting, participants, & measurements In total, 33,263 dialysis patients with an eGFR measure at dialysis initiation between January of 2001 and December of 2010 representing 63 dialysis facilities and 14 geographic regions were included in the study. Multilevel models and intraclass correlation coefficients were used to evaluate the variation in timing of dialysis initiation by eGFR at the patient, facility, and geographic levels.Results The proportion initiating dialysis with an eGFR$10.5 ml/min per 1.73 m 2 was 35.3%, varying from 20.1% to 57.2% across geographic regions and from 10% to 67% across facilities. In an unadjusted, intercept-only linear model, 90.7%, 6.6%, and 2.7% of the explained variability were attributable to patient, facility, and geography, respectively. After adjustment for patient and facility factors, 96.9% of the explained variability was attributable to patient case mix, 3.1% was attributable to the facility, and 0.0% was attributable to the geographic region. These findings were consistent when the eGFR was categorized as a binary variable ($10.5 ml/min per 1.73 m 2 ) or in an analysis limited to patients with .3 months of predialysis care.Conclusions Patient characteristics accounted for the majority of the explained variation regarding the eGFR at the initiation of dialysis. There was a small amount of variation at the facility level and no variation among geographic regions that was independent of patient-and facility-level factors.

What Drives Early Dialysis Initiation and How Do We Optimize Timing of RRT?

“…The authors observed that patient-related factors accounted for .95% of the explained variability of eGFR at dialysis initiation (8). Many of the specific patient characteristics associated with earlier dialysis initiation are similar to those previously observed in United States cohorts (2,7,9), and include female sex and presence of comorbidities.…”

“…In the Canadian study, facility characteristics explained only 3.1% of eGFR variability with increase in interfacility variation among hemodialysis patients compared with PD patients (8). It is no surprise that the dialysis facility has little influence over the timing of dialysis initiation.…”

“…The study by Sood et al also demonstrated an association between lower phosphorus levels and earlier dialysis initiation (8). Although this may represent poor nutritional status, it may also represent residual confounding.…”

“…The link between the facility and the patient's timing of dialysis initiation is likely mediated through the provider. Unfortunately, in the study by Sood et al, there was no information available about the provider (8).…”

“…Prior studies have evaluated both patient and provider characteristics associated with timing of dialysis initiation (2,7). In this issue of CJASN, Sood et al aimed to determine how patient, facility, and geographic characteristics influence the variation of eGFR at dialysis initiation across Canada (8).…”