The prevalence of rheumatoid arthritis in Argentina: a capture-recapture study in a city of Buenos Aires province.

ABSTRACT

OBJECTIVE: The objective of this study was to assess the prevalence of rheumatoid arthritis (RA) in the population of a city of 70,000 inhabitants located in Buenos Aires, Argentina. METHODS: Based on the hypothesis that RA is an underdiagnosed disease in Argentina, a capture-recapture method was applied. A local registry of RA patients of Luján City was taken as the primary source; a telephone survey was specifically carried out as a secondary source of information. Patients suspected of having RA were referred to a local hospital to be examined by a team of 12 rheumatologists. Anamnesis and physical examination were followed by hand and foot radiography and erythrocyte sedimentation rate and rheumatoid factor measurements. RESULTS: According to the American College of Rheumatology criteria, a prevalence rate of 0.94% (95% confidence interval [CI], 0.86%-1.02%) was found in the surveyed population; in agreement with other studies, this prevalence was higher in women when compared with men (for female, 1.54% [95% CI, 1.40%-1.69%]; for male, 0.40% [95% CI, 0.32%-0.49%]). CONCLUSION: The prevalence of RA in a representative sample of the population of a city from the central region of Argentina seems to be close to 1%.