title: Lack of correlation of the health assessment questionnaire disability index with lung parameters in systemic sclerosis associated pulmonary arterial hypertension.
abstract: OBJECTIVE
  Pulmonary arterial hypertension (PAH) affects the quality of life (QoL) and the ability to perform the activities of daily living (ADLs) in patients with systemic sclerosis (SSc). We determined whether the Health Assessment Questionnaire-Disability Index (HAQ-DI), a self-assessment measure of function, correlates with a patient's PAH status in a population of SSc patients with PAH.
  
  
  METHODS
  Forty-one patients from one centre with systemic scleroderma, dyspnea and PAH were included. All patients filled in a HAQ-DI, and underwent evaluation with pulmonary function tests (PFTs), 6-minute walk distance (6MWD), degree of dyspnea (Borg dyspnea index), NYHA functional class, and expert PAH physician global assessment every 6 months. Change in HAQ DI was studied to determine relationship to changes in PAH.
  
  
  RESULTS
  The HAQ-DI scores had no significant correlation with PAH, including NYHA functional class (r=0.38, p=0.39), Borg dyspnea index (r=0.60, p=0.37), 6MWD (r=-0.04, p=0.86), % predicted DLCO (r=0.31, p=0.25), % predicted FVC (r=0.02, p=0.93), and expert PAH physician global assessment (r=0.06, p=0.97).
  
  
  CONCLUSIONS
  HAQ-DI is not an adequate measure of PAH status in SSc patients with PAH. Although PAH causes severe morbidity and death, changes in PAH severity were not reflected in an overall functional status change as assessed by the HAQ-DI. Thus, HAQ-DI changes do not reflect PAH status in SSc.
authors.affiliation: Departments of Rheumatology and Respirology, Schulich School of Medicine, University of Western Ontario, London, Ontario, Canada.
authors.forename: S
authors.initials: S
authors.lastname: Chow
authors.forename: J E
authors.initials: JE
authors.lastname: Pope
authors.forename: S
authors.initials: S
authors.lastname: Mehta
mesh_terms: D000328:Adult; D000368:Aged; D004185:Disability Evaluation; D004417:Dyspnea / Q000453:epidemiology / Q000503:physiopathology; D006304:Health Status; D006801:Humans; D006976:Hypertension, Pulmonary / Q000453:epidemiology / Q000503:physiopathology*; D008875:Middle Aged; D009017:Morbidity; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D012307:Risk Factors; D012595:Scleroderma, Systemic / Q000453:epidemiology / Q000503:physiopathology*; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires / Q000592:standards*