Increasing age at onset has been associated with worse outcome in rheumatoid arthritis (RA) though there are few data from unselected inception cohorts. We tested the hypothesis that increasing age is associated with a higher risk of erosions at presentation, and that this increase is not explained by age-related disease confounders. SUBJECTS: and methods: 222 subjects (median onset age 59 years) were studied from a primary-care based register of new onset inflammatory polyarthritis patients with hand and feet radiographs taken within 12 months from symptom onset. Films were scored by 2 readers using the Larsen score. The risk of erosions in those aged 50-69 and inverted exclamation markY70 years at onset was compared to those aged under 50, both before and after adjustment for possible age-related disease variables. RESULTS: The prevalences of erosions were 22%, 52% and 71% in those aged