Sparing of age-related macular degeneration in rheumatoid arthritis.

Age-related macular degeneration (AMD), for which inflammatory changes have been demonstrated, is the commonest cause of blindness in the elderly. We compared the prevalence of AMD in a prospectively followed cohort of rheumatoid arthritic (RA) patients from Saskatchewan with published data from four racially similar general populations. For individuals 65 years or older, only three cases of AMD were identified in the Saskatchewan cohort of 993 RA patients (0.2% prevalence). This compares with 67 out of 1955 subjects in the Beaver Dam survey (prevalence 3.43%); 101 out of 4071 in the Rotterdam survey (prevalence 2.48%); and 63 out of 1950 in the Blue Mountains survey (prevalence 3.23%). For individuals 75 years or older, only two cases out of 497 were identified in the RA cohort (prevalence 0.40%), compared with 516 cases out of 13,900 in the United Kingdom survey (prevalence 3.72%). Patients with RA appear to be relatively spared from AMD. We hypothesize that this results from long term antiinflammatory treatment. Genetic or environmental factors could also be responsible.