Survival of incident RRT patients in the UK (Chapter 12)

Abstract

This analysis presents the survival of patients starting renal replacement therapy (RRT) in UK renal units ('centres'), and includes an analysis of survival by centre. Data from 59 of the 70 UK centres are included. This is the first year that UK centre anonymity has been removed from analysis of patient survival by centre. Survival after adjustment for comorbidity is also reported for the first time although this analysis is restricted to those centres returning data on comorbidity in at least 85% of incident patients. The importance of adjusting for comorbidity can be seen in that for one centre, after adjustment of survival for age and diagnosis, the adjusted 1 year after 90 day survival was 84.6%. After adjusting to the average comorbidity present across centres, survival increased to 90.4%. Improved comorbidity data returns by renal units may require investment in informatics staff and creating structural process at renal unit level for clinicians to support these data returns. From the date of first RRT, the 1 year survival of all patients (unadjusted for age) is 79%. From the 90th day of RRT (to allow comparison with other countries' 1 year survival), the 1 year survival is 83%. The age adjusted (60 years) survival for the 1 year after 90 day period is 86%. There is a high death rate in the first 90 days on RRT (6% of all patients starting RRT), a period not included in reports by many registries and other studies. The 5 year survival (including deaths within the first 90 days) rates are 58, 53, 44, 28, 19 and 12%, respectively for patients aged 18-34, 35-44, 45-54, 55-64, 65-74 and >75 years. The 'vintage effect' of increasing hazard of death with length of time on RRT, prominent in data from the US, is only noted in older age groups (65-75 and 75+ years) at 5-6 years after starting RRT. Six centres had a figure for the 1 year after 90 day survival which was outside 2 SDs from the mean for the UK: in three cases this was better survival, and in three, poorer survival, than expected. Poor reporting by renal units of patient comorbidity makes interpretation of these apparent differences in patient survival between centres difficult and a relationship to clinical performance cannot yet be inferred.