Open AccessCorrelates of the disability index of the health assessment questionnaire: A measure of functional impairment in systemic sclerosis
Author(s) -
Clements Philip J.,
Wong Weng Kee,
L. Hurwitz Eric,
Furst Daniel E.,
Mayes Maureen,
White Barbara,
Wigley Fredrick,
Weisman Michael,
Barr Walter,
Moreland Larry,
Medsger Thomas A.,
Steen Virginia,
Martin Richard,
Collier David,
Weinstein Arthur,
Lally Edward,
Varga John,
Weiner Steven,
Andrews Brian,
Abeles Micha,
Seibold James
Publication year - 1999
Publication title -
arthritis & rheumatism
Language(s) - English
Resource type - Journals
eISSN - 1529-0131
pISSN - 0004-3591
DOI - 10.1002/1529-0131(199911)42:11<2372::aid-anr16>3.0.co;2-j
Subject(s) - medicine , odds ratio , confidence interval , logistic regression , scleroderma (fungus) , body mass index , physical therapy , pathology , inoculation
Objective To evaluate functional impairment in systemic sclerosis (SSc) patients with diffuse cutaneous scleroderma at the time of entry into a trial of a therapeutic intervention (D‐penicillamine). Methods The 20‐item Disability Index of the Health Assessment Questionnaire (HAQ‐DI) was administered to 134 patients as they entered a multicenter trial of high‐dose versus low‐dose D‐penicillamine. All patients had diffuse SSc of <18 months' duration. SSc patients who had severe organ system involvement and recent renal crisis and who were receiving prednisone >10 mg/day were excluded from entry. Logistic regression modeling was used to examine the relationship of HAQ‐DI scores to SSc skin and organ system involvement. Odds ratios (OR) and 95% confidence intervals (95% CI) were used to estimate effects. Results The mean (±SD) HAQ‐DI score at entry was 1.04 ± 0.67. Fifty‐three percent of patients had HAQ‐DI scores ≥1.0 (signifying moderate‐to‐severe functional impairment). Multivariate logistic regression demonstrated that impaired fist closure ≥23 mm (OR 4.24, 95% CI 1.68–10.70), reduced handspread ≤175 mm (OR 4.5, 95% CI 1.80–11.24), joint tenderness count ≥1.0 (OR 2.93, 95% CI 1.16–7.40), age ≥43 years (OR 2.44, 95% CI 1.01–5.95), platelet count ≥330,000/mm 3 (OR 2.30, 95% CI 0.96–5.57), and female sex (OR 2.43, 95% CI 0.77–7.73) were the most important correlates of HAQ‐DI scores ≥1.0. Conclusion Increased HAQ‐DI scores at baseline were correlated with reduced fist closure, reduced handspread, elevated platelet count, presence of tender joints, older age, and female sex. The most important contributor to functional impairment was hand dysfunction. Even within the first 18 months after SSc onset, moderate–severe functional impairment (HAQ‐DI scores ≥1.0) was frequent (53%) in this group of diffuse SSc patients. In early diffuse SSc, the self‐administered HAQ‐DI is therefore a valuable assessment of function that correlates with objective physical and laboratory measures of SSc disease involvement. Abnormal HAQ‐DI scores may support patient claims of functional impairment, help to focus physician attention on implementing measures to reduce functional impairment, and be useful in reflecting the disease course over time.