Renal replacement therapy in the Canary Islands: demographic and survival analysis

BACKGROUND: The continuous increase in the number of patients on renal replacement therapy (RRT) has heightened the importance of renal patient registries to respond to the demand for data on the state of health, quality and cost of care provided for these patients. Our aim was to analyze the epidemiological profile of this population in the Canary Islands. METHODS: All patients on RRT between January 1999 and December 2003 were considered in this analysis. The information was obtained from the database of the Canary Registry of Renal Patients. RESULTS: We observed a continuous increase in incidence throughout the study period (from 138 per million population (pmp) in 1999 to 160 pmp in 2003), being more evident in patients >65 yrs. Prevalence followed a similar course, increasing from 875 to 972 pmp, being especially evident in the 65-74 yr age group. An alarming finding was the high incidence (43.5%) and prevalence (37.5%) of diabetic nephropathy. While the proportion of hemodialysis (HD) or transplant patients increased, that of peritoneal dialysis (PD) remained low and stable (prevalence of 5% in 2003). Almost half the RRT patients had functioning grafts, with a notably high rate of 58 transplants pmp in 2003, and a prevalence of 425 pmp. Age (hazard ratio (HR) [95% confidence interval (95% CI)] 1.04 [1.03-1.05]; p < 0.001) and diabetic nephropathy (1.47 [1.19-1.82]; p < 0.001) were independently associated with mortality in dialysis patients. Those returning to dialysis after graft loss had a 69% greater risk of death than incident dialysis patients (1.69 [1.06-2.69]; p = 0.026). Cardiovascular events were the main cause of death in all dialysis modalities. Patient death was the main cause of graft loss. CONCLUSIONS: The most outstanding finding was the high incidence and prevalence of patients on RRT, mainly due to diabetic nephropathy. Renal transplant rates were among the highest reported in renal patient registries.