SURVIVAL ON RENAL REPLACEMENT THERAPY IN EUROPE - IS THERE A CENTER EFFECT

Objective. Survival is the ultimate outcome measure in renal replaceme nt therapy (RRT) and may be used to compare performance among centres. Such comparison, however, is meaningless if the influences of comorbi dity, age and early deaths are not considered. We therefore studied su rvival rates on RRT in seven centres in Europe after taking into accou nt the influence of age, early deaths, primary renal diagnoses, and co morbidity. Design. A retrospective survival analysis was carried out o n 1407 patients who commenced RRT in seven centres across five Europea n countries during a 7-year period. Patients were stratified into low- , medium- and high-risk groups based mainly on comorbidity and to a le sser extent on age at commencement of RRT. Kaplan-Meier survival and C ox's proportional hazards model were used to compare survival. Results . Before risk stratification overall 2-year survival across the seven centres ranged from 60.2 to 85.3% (69.3-89.9% after excluding early de aths) masking a range of survivals of 27.4% for the high-risk group wi th the worst survival to 100% in the low-risk group with the best surv ival. After excluding early deaths 2-year survival in the low risk gro ups (n = 596) was greater than 90% in all centres. Multivariate analys is showed that the mortality risk increased four fold from low- to med ium- and a further 1.6-fold from medium- to high-risk group. However, despite this adjustment for comorbidity and age there still remained a significant difference in survival among some centres, i.e. a 'centre effect' which ranked the centres. Conclusion. Risk stratification dim inishes the variance in survival between centres but a centre effect r emains despite adjusting for age and comorbidity. Multicentre prospect ive studies are urgently required to identify the reasons for this app arent centre effect.