Extra-articular manifestations in 587 Italian patients with rheumatoid arthritis.

The aim of the study was to evaluate the frequency of extra-articular manifestations (EAMs) of rheumatoid arthritis (RA) in a series of patients from nine Italian rheumatology clinics. A total of 587 patients underwent direct questioning, complete physical evaluation, and review of medical records and laboratory data. The relationships between EAMs and the eosinophilic count, IgM rheumatoid factor (RF), and antinuclear antibodies (ANA) were studied. EAMs were present in 240/587 (40.9%) patients. The most common features were sicca syndrome (17.5%) and rheumatoid nodules (16.7%). EAMs were significantly more frequent in male patients (OR = 1.68), patients with ANA positivity (OR = 2.82), high anatomical class (OR = 2.3), and rheumatoid factor seropositivity (OR = 2.22). EAMs were more common in patients from southern Italy than in those from northern Italy (P < 0.001). EAMs seem to be rarer in Italy than in the Anglo-Saxon populations of northern Europe and the USA. Differences in prevalence of EAMs can exist even within the same country.