The clinical features, serology behaviour, scintiscan characteristics and the degree of X-ray progression according to the disease duration were compared in two RA groups with a disease onset after 65 years of age (LORA) and before 65 (EORA) respectively. No differences emerged in either the clinical findings or in the scintiscan picture. A sub-group of LORA showed acute flares of the illness presenting with very high ESR values and high fever. The erosive index (EI) evaluated in three areas (carpal-bone and wrist, MCP and PIP joints) revealed an undistinguishable degree of X-ray damage either in seropositive or seronegative patients, whereas seropositive EORA fared clearly worse than seronegative ones. A prospective study in two small sub-groups of LORA and EORA revealed a progression of X-ray erosions despite second line drug treatment in both groups, especially in LORA.