Factors influencing long-term survival in patients on chronic dialysis.

Japan has the highest prevalence of dialysis patients in the world. According to the Annual Report of the Japanese Society for Dialysis Therapy (JSDT; 2002), the total dialysis population was 229 538 (1801.5 patients per million population) at the end of 2002. The annual crude mortality rate has been less than 10%. Survival rates in the incident dialysis patients were 0.874 for 1 year, 0.609 for 5 years, and 0.391 for 10 years. Despite the increased acceptance for dialysis of elderly patients, those with comorbid conditions, and those with diabetes mellitus, the adjusted hazard ratios for death have been improving since 1983. This improvement was obtained by delivering a dialysis dose of Kt/V 1.33 and dialysis sessions of 4 h. Independently of the JSDT registry, there exists a local dialysis registry in Okinawa, the Okinawa Dialysis Study (OKIDS) registry, in which are filed the records of every chronic dialysis patient from the beginning of dialysis therapy in 1971 to the end of 2000. Several outcome studies have been conducted to determine the factors related to survival, using the data in that registry. There are distinct differences in environmental and socioeconomic conditions and lifestyles within a given country, and between countries and ethnic groups, that may affect the survival of dialysis patients. In this article, both the JSDT registry and OKIDS data are reviewed in order to identify factors related to the survival of chronic dialysis patients.