The increase in the incidence of elderly patients starting dialysis has been as sharp, during the 1980s-1990s, as an epidemic (+70%, +150% in different settings). According to this study, performed in Piemonte, northern Italy, the process is still ongoing. During the period 1981-93, according to the Regional Registry of Dialysis and Transplantation (RPDT: data on 100% of centres and patients), the cohort on treatment increased by 79.5% and the annual incidence by 48.3%; the increase is limited to older people and is greater in males. Nephroangiosclerosis/ischaemic renal disease and diabetes mellitus are the main diagnoses. Since the increase of elderly patients is still ongoing, forecasts are difficult; according to a computer simulation, a plateau of patients on treatment is reached only if incidence is stabilized, While it is impossible to exclude a decrease in hidden selection or an increase in referral, complex modifications at the overall population level are presumably at the basis or the increase of elderly patients on dialysis. Despite the increase in average age, however, survival improved throughout the period; this confirms the interest towards the open dialysis system adopted in Piemonte, which is characterized by easy shifts among treatments and by the widespread use of high tolerance techniques.