|Increasing prevalence - dialysis|
|Professionals - Epidemiology|
Increasing prevalence of End-Stage Kidney Disease (ESKD) in adult patients treated by dialysis in the Republic of Ireland between 31/12/2003 and 31/12/2008
W.D. Plant (1,2) & F. MacHale(1)
1) Health Service Executive National Renal Office; 2) Department of Renal Medicine, Cork University Hospital
There is not yet a National Renal Registry in the Republic of Ireland. Until this is established, it is difficult to access epidemiological data to inform future planning and configuration of End-Stage Kidney Disease (ESKD) services.
To estimate (with as much validity as is possible) the growth in numbers of adult ESKD patients treated by dialysis in the Republic of Ireland between 31/12/03 and 31/12/08 and to evaluate patterns of growth in the numbers treated by haemodialysis (HD) and peritoneal dialysis (PD).
Over the last 6 years, the National Renal Strategy Review (NRSR), the National Hospitals’ Office of the HSE and the National Renal Office (NRO) have conducted an Annual Survey of activity in Renal Units in the Republic of Ireland.
The annual census date is 31st December. Data collection utilises a standardised self-report survey instrument. The survey is not patient-linked and does not have a mechanism for external validation of the self-reported data provided by each Unit.
Data generated by these Surveys were examined to generate the descriptive epidemiological results presented. Data from the Central Statistics Office Census 2002 and 2006 were used to define populations. Rates are expressed per million population (p.m.p.)
The total number of patients treated for ESKD by dialysis rose from 1013 (258 p.m.p.) on 31/12/03 to 1601 (377 p.m.p.) on 31/12/08.
This represents an increase of 588 patients (58%) over 5 years. Almost all (575) of this increase was in the numbers treated by HD. Those treated by HD have increased by 70%.
Table 1 illustrates the national prevalence of HD and PD patients on each of the 6 Survey dates. Although absolute numbers of those treated by PD have changed little, the proportion treated by this modality has declined from 18% to 12%.
Table 1: Prevalence of ESKD patients, by dialysis modality, on 31st December each year. *2006 Census
The increment in patient numbers during each of the years 2004-2008 has been highly variable (Table 2). There are insufficiently detailed data from the earlier Surveys to allow for robust commentary on increments/decrements within smaller catchment areas (such as HSE Areas). Table 3 illustrates the mean (95% confidence interval (C.I.)) growth observed for both modalities during this period of observation. The denominator population changes in 2006, reflecting the rise in population observed in the National Census 2006, compared with that observed in 2002.
Table 2: Annual increase in ESKD patients, by dialysis modality.
Table 3: Mean and spread of the increase in ESKD patients, by dialysis modality, over 5 years.
These data illustrate the very significant variation that occurs from year to year in the growth of the ESKD population treated by dialysis. The wide variation in the 95% C.I. for mean increment makes future planning of ESKD services to a high level of precision difficult.
Most growth occurs within the HD population. Recalling that most patients treated by HD require at least 156 treatments per annum, we note a rise in total annual HD treatments from c.129,000 in 2003 to c.219,000 in 2008. HD patients now have c.444,000 trips to and from HD facilities each year.
The prevalence of ESKD treated by dialysis has increased by 58% in the last 5 years. The prevalence of ESKD treated by HD has increased by 70% in that interval.
The annual increment is very variable (and has geographical variation within it) making future planning of ESKD services difficult. Anticipating relatively little change in numbers treated by PD seems reasonable. Anticipating a mean annual increment in HD patients of between 20 and 30 p.m.p. seems reasonable (85 to 130 individuals). However, spare capacity is needed to cover for potential increases of up to 45 p.m.p. in a single year.