Trends in the incidence, sociodemographic characteristics, and comorbidities of patients starting their first dialysis treatment were studied in nine French regions participating in the Rein registry (Network for Epidemiology and Information in Nephrology) from 2004 to 2007. These trends are characterized by a stable number of patients treated and an increase in their age. Overall, the number of comorbidities remains stable, but after adjusting for age, there is a decrease in cardiovascular comorbidities. These results, combined with changes in biological parameters, suggest that despite the aging of patients, there is no deterioration in their health status and that the management of chronic kidney disease has improved, thus generating cautious optimism for the future. (R.A.)