ABSTRACT
OBJECTIVE: To confirm the reliability and applicability of the Polymyalgia Rheumatica Disease Activity Score (PMR-AS), and to establish a threshold for remission. METHODS: First, 78 patients with PMR (50 women/28 men, mean age 65.97 years) were enrolled in a cross-sectional evaluation. The PMR-AS, patient's satisfaction with disease status (PATSAT; range 1-5), erythrocyte sedimentation rate (ESR; first hour), and a visual analog scale of patients' general health assessment (VAS patient global; range 0-100) were recorded. Subsequently, another 39 PMR patients (24 women/15 men, mean age 68.12 years) were followed longitudinally. Relationships between the PMR-AS, PATSAT, ESR, and VAS patient global were analyzed by the Kruskal-Wallis test, Spearman's rank correlation, and kappa statistics. PMR-AS values in patients with a PATSAT score of 1 and a VAS patient global <10 formed the basis to establish a remission threshold. RESULTS: PMR-AS values were significantly related to PATSAT (P < 0.001), VAS patient global (P < 0.001), and ESR (P < 0.01). PATSAT and VAS patient global were reasonably different (kappa = 0.226). The median PMR-AS score in patients with PATSAT score 1 and VAS patient global <10 was 0.7 (range 0-3.3), and the respective 75th percentile was 1.3. To enhance applicability, a range from 0 to 1.5 was proposed to define remission in PMR. The median ESR in these patients was 10 mm/hour (range 3-28), indicating external validity. CONCLUSION: We demonstrated the reliability, validity, and applicability of the PMR-AS in daily routine. Moreover, we proposed a remission threshold (0-1.5) founded on patient-dependent parameters.
Subject(s)
Glucocorticoids/therapeutic use , Health Status , Polymyalgia Rheumatica , Severity of Illness Index , Adult , Aged , Aged, 80 and over , Blood Sedimentation , Cross-Sectional Studies , Female , Humans , Longitudinal Studies , Male , Middle Aged , Patient Satisfaction/statistics & numerical data , Polymyalgia Rheumatica/diagnosis , Polymyalgia Rheumatica/drug therapy , Polymyalgia Rheumatica/physiopathology , Remission Induction , Reproducibility of Results , Treatment OutcomeABSTRACT
OBJECTIVE: To assess the factorial structure of the Disease Activity Score including a 28-joint count (DAS28) if applied in patients with rheumatoid arthritis (RA) and psoriatic arthritis (PsA). METHODS: DAS28 values from 85 consecutive PsA outpatients and 2 RA patient cohorts comprising 85 patients each were compared. The first RA cohort (RA1) consisted of age- and sex-matched patients seen during the same period as the patients with PsA. The first 85 RA outpatients from September 2003 were included in the second cohort (RA2). Item weighting, factor loading, and internal consistency were assessed by factor analysis, principal component analysis, and calculation of Cronbach's alpha. RESULTS: The mean +/- SD DAS28 scores of patients in the PsA, RA1, and RA2 cohorts were 3.2 +/- 1.31, 3.21 +/- 1.45, and 3.79 +/- 1.44, respectively. A significant difference between the PsA and RA2 cohorts was found for DAS28 (P = 0.0063), swollen joint count (P = 0.007), and patient's global assessment (P < 0.001), but not for erythrocyte sedimentation rate. Internal consistency of the DAS28 in patients with PsA was considerably lower, item weighting showed remarkable differences, and factor analysis revealed that the DAS28 constitutes a bidimensional instrument in patients with PsA, whereas in both RA cohorts it appeared to be monodimensional. CONCLUSION: With respect to its statistical properties, the DAS28 proved to be considerably different in PsA compared with RA. Therefore its application for disease activity assessment in patients with PsA cannot be recommended without a formal validation procedure.
