Late onset systemic lupus erythematosus: no substantial differences using different cut-off ages.

To compare the clinical, laboratory and immunological features of a group of Caucasian systemic lupus erythematosus (SLE) patients in relation to age at disease onset. Three groups of patients with different ages at disease onset were analysed and compared: group A (30 patients, >or=65 years); group B (62 patients, 50-64 years) and group C (163 patients, <50 years). All patients were regularly followed-up for a mean period of 6.5 years. Female predominance was reduced in groups A and B. Time-lapse between disease onset and diagnosis was longer in group A and B. There were no statistically significant differences in clinical features. The only relevant difference was observed in peripheral nervous system (PNS) involvement, more frequent in group A. Anti-dsDNA and RF were more frequent in group A. Complement levels were reduced more frequently in group C. No differences were observed in disease activity scores, while SLICC/ACR score was higher in group A. In Caucasian SLE patients, age at disease onset is not associated with differences in clinical features apart from a more frequent PNS involvement in elderly patients. In the same group, the organ damage seems to develop more rapidly mostly due to higher susceptibility to jatrogenic side effects.