Prevalence of Inflammatory Back Pain in a Low-Income Population.

BACKGROUND: Inflammatory back pain (IBP) is a major criterion in identifying axial spondyloarthritis. Whether socioeconomic issues impact prevalence of IBP assessed using standardized questionnaires has not been assessed. We determined IBP prevalence and performance of IBP questionnaires in a low-income, low-literacy population. METHODS: Individuals were interviewed in Fortaleza, Brazil, for the prevalence of IBP using Calin's, Berlin, and ASAS IBP questionnaires; monthly family income (US dollars), literacy (>/≤8 school years [SYs]), and smoking habit (present/absent) were registered. RESULTS: Two hundred nineteen individuals were included (mean age, 38.2 ± 12.9 years), 110 (50.2%) men, 58 (26.4%) White, and 38 (17.3%) smokers. Overall, 152 (69.4%) declared