Epidemiology of musculoskeletal symptoms, rheumatologic disorders, and disability in the Zoroastrian population in Yazd, Iran: a WHO-ILAR COPCORD study (stage 1)

Background: The purpose of this study was to determine the prevalence of musculoskeletal complaints, rheumatologic diseases, and disability among the Zoroastrian population in Iran. Methods: The city of Yazd, in central Iran was selected for this study, with the highest population of Zoroastrians in Iran. Subjects were selected by cluster sampling of 9 neighborhoods populated with Zoroastrians. Subjects >= 15 years old were interviewed by trained interviewers in their houses. The validated Farsi translation of Community Oriented Program for the Control of Rheumatic Disease (COPCORD) Core Questionnaire (CCQ) was used for this study. Subjects with musculoskeletal complaints (pain, stiffness and/or swelling) were examined by a rheumatologist. Laboratory tests and radiographic exams were performed when deemed necessary. Results: Two-thousand subjects were interviewed during a 12-month period, of which 956 were male, and 1044 were female. The mean age was 41.1 +/- 18.3 years (95%CI: 40.3-41.9). 36.9% of the subjects had university-level education. In the 7 days prior to the interview, 27.6% of the subjects had musculoskeletal complaints, with the knee, dorsolumbar spine, and shoulder being the most common sites of complaints. The most common rheumatologic diagnoses were osteoarthritis (21.5%) and low back pain (10.3%). Rheumatoid arthritis was diagnosed in 1.2% of the subjects. Conclusions: The epidemiology of musculoskeletal complaints and rheumatologic disorders was inconsistent with previous COPCORD studies in Iran, with a lower prevalence of musculoskeletal complaints in general, lower rates of Behcet and lupus, and a higher prevalence of rheumatoid arthritis. The findings of this study can be for development of better prevention, screening, and treatment programs for the vulnerable population of Zoroastrians in Iran.