HOSPITALIZATION AMONG UNITED-STATES DIALYSIS PATIENTS - HEMODIALYSIS VERSUS PERITONEAL-DIALYSIS

Measurements of hospitalization in the dialysis population are important because they provide insight into the morbidity and the cost of treatment among dialysis patients. Prior comparisons of hospitalization for different dialysis modalities have had conflicting results. This study was designed to compare hospitalization for patients treated with peritoneal dialysis (PD) versus hemodialysis (HD) using the data from the U.S. Renal Data System 1993 Annual Data Report. The study population included all Medicare dialysis patients prevalent on January 1, 1988 through 1990. Patients were monitored to transplantation, death, or end of the calendar year for a total of 189,654 patient years. Hospital admission rates were computed from the total number of hospital admissions during the year divided by the total number of patient years at risk. Patients were classified by treatment modality (PD, HD), cause of ESRD (diabetes as a cause of ESRD versus all other causes), age (0 to 19, 20 to 44, 45 to 65, +65), and race (black, white). Rate ratios (RR:PD/HD) for hospital admissions per year at risk were estimated, while adjusting for the other factors with Poisson regression. On average, hospital admission rates per patient year at risk for dialysis patients treated with PD were 14% higher than for those treated with HD (RR = 1.14; 95% confidence interval (Cl), 1.13 to 1.15) when adjusting for race, age, gender, and cause of ESRD. The excess in the overall adjusted admission rates in PD patients compared with HD patients was higher for black than for white patients (RR:PD/HD = 1.22 versus RR = 1.11; 95% Cl, 1.10 to 1.13). The RR:PD/HD was significantly above 1.0 across all age groups. Diabetic patients treated with PD had higher admission rates per patient year at risk than did diabetics treated with HD (RR = 1.12; 95% Cl, 1.10 to 1.14), which was confirmed across all age groups except for the younger diabetic patients (age 20 to 44 yr), who had similar admission rates for PD and HD. The finding of higher hospitalization rates among continuous ambulatory PD compared with HD patients deserves further study to consider the causes for hospitalization and the role of unmeasured factors such as delivered dialysis dose and patient selection.