Objective: To compare Health Assessment Questionnaire (HAQ) scores of patients with rheumatoid arthritis (RA) with HAQ scores from a sex- and age-adjusted population.
Methods: Patients with RA (n = 1,095) and control subjects (n = 1,530) completed a mailed questionnaire that comprised the HAQ, pain and global health scores, education level, and comorbidities, as well as height, weight, and lifestyle attitudes, including smoking and exercise habits.
Results: The HAQ scores increased (indicating declining function) with older age in patients and controls. The HAQ scores were above the reference values (>95th percentile of the HAQ scores of the age- and sex-matched population) in 17-45% of women with RA and in 7-32% of men with RA ages 30-79 years, while the HAQ scores of the patients > or =80 years were similar to those of the age- and sex-matched population. In a logistic regression model, the odds ratio for disability (HAQ score > or =1; at least some difficulties in most activities of daily living) was 7.7 (95% confidence interval 5.3-11.1; P < 0.001) among patients with RA compared with community controls, when adjusted for age, sex, education, smoking, exercise, body mass index, number of comorbidities, and pain.
Conclusion: RA is associated with a >7-fold risk of disability compared with that in a general population of adults in the same community. The impact of disability due to RA appears to be greater in younger and middle-age people than in elderly patients.