Impact of Comorbidity on Physical Function in Patients With Ankylosing Spondylitis and Psoriatic Arthritis Attending Rheumatology Clinics: Results From a Cross-Sectional Study.

OBJECTIVE: To evaluate the impact of comorbidities on physical function in patients with ankylosing spondylitis (AS) and psoriatic arthritis (PsA). METHODS: This was a cross-sectional analysis of the baseline visit from the Cardiovascular in Rheumatology study. Multivariate models with physical function as the dependent variable (Bath Ankylosing Spondylitis Functional Index and Health Assessment Questionnaire for AS and PsA, respectively) were performed. Independent variables were a proxy for the Charlson Comorbidity Index (CCIp; range 0-27), sociodemographic data, disease activity (erythrocyte sedimentation rate [ESR] and Bath Ankylosing Spondylitis Disease Activity Index [BASDAI] in AS; Disease Activity Score in 28 joints [DAS28] using the ESR in PsA), disease duration, radiographic damage, and treatments. Results were reported as beta coefficients, 95% confidence intervals (95% CIs), and P values. RESULTS: We included 738 patients with AS and 721 with PsA; 21% of patients had >1 comorbidity. Comorbidity burden (CCIp) was independently associated with worse adjusted physical function in patients with PsA (ß = 0.11). Also, female sex (ß = 0.14), disease duration (ß = 0.01), disease activity (DAS28-ESR; ß = 0.19), and the use of nonsteroidal antiinflammatory drugs (ß = 0.09), glucocorticoids (ß = 0.11), and biologics (ß = 0.15) were associated with worse function in patients with PsA. A higher education level was associated with less disability (ß = -0.14). In patients with AS, age (ß = 0.03), disease activity (BASDAI; ß = 0.81), radiographic damage (ß = 0.61), and the use of biologics (ß = 0.51) were independently associated with worse function on multivariate analyses, but CCIp was not. CONCLUSION: The presence of comorbidities in patients with PsA is independently associated with worse physical function. The detection and control of the comorbidities may yield an integral management of the disease.

Power Doppler ultrasonography assessment of entheses in spondyloarthropathies: response to therapy of entheseal abnormalities.

OBJECTIVE: To investigate the response to therapy of entheseal abnormalities assessed with power Doppler (PD) ultrasound (US) in spondyloarthropathies (SpA). METHODS: A total of 327 patients with active SpA who were starting anti-tumor necrosis factor (TNF) therapy were prospectively recruited at 35 Spanish centers. A PDUS examination of 14 peripheral entheses was performed by the same investigator in each center at baseline and at 6 months. The following elementary lesions were assessed at each enthesis (presence/absence): morphologic abnormalities (hypoechogenicity and/or thickening), entheseal calcific deposits, cortical abnormalities (bone erosion and/or proliferation), adjacent bursitis and intraenthesis and perienthesis (tendon body and/or bursa) PD signal. Response to therapy of each elementary lesion was assessed by calculating change in the cumulative presence from baseline to 6 months. Intraobserver reliability of PDUS was evaluated by blindly assessing the stored baseline images 3 months after the real-time examination. RESULTS: Complete data were obtained on 197 patients who received anti-TNF therapy for 6 months. In 91.4% of the patients there were gray-scale or PD elementary lesions at baseline and at 6 months. Cumulative entheseal morphologic abnormalities, intraenthesis PD, perienthesis PD, and bursitis showed a significant decrease from baseline to 6 months (p < 0.05). There was high intraobserver reliability for all elementary lesions (interclass correlation coefficient > 0.90, p < 0.0005). CONCLUSION: Entheseal morphologic abnormalities, PD signal, and bursitis were US abnormalities that were responsive to anti-TNF therapy in SpA. PDUS can be a reproducible method for multicenter monitoring of therapeutic response in enthesitis of SpA.

Validity, reproducibility, and responsiveness of a twelve-joint simplified power doppler ultrasonographic assessment of joint inflammation in rheumatoid arthritis.

OBJECTIVE: To investigate the validity, reproducibility, and responsiveness of a simplified power Doppler ultrasound (PDUS) assessment of joint inflammation compared with a comprehensive 44-joint PDUS assessment in patients with rheumatoid arthritis (RA) who started therapy with a biologic agent. METHODS: A total of 160 patients with active RA who started a biologic agent were prospectively recruited in 18 Spanish centers. The patients underwent clinical and laboratory assessment and blinded PDUS examination at baseline and 6 months. A PDUS examination of 128 synovial sites in 44 joints was performed. US synovitis and PD signal were semiquantitatively graded from 1 to 3 in all synovial sites. US count and index for synovitis and PD signal were obtained. PDUS intraobserver and interobserver reliability were evaluated. A process of data reduction based on the frequency of involvement of synovial sites by both synovitis and PD signal was conducted. Construct and discriminant validity of a simplified PDUS assessment was investigated. RESULTS: A PDUS simplified assessment including 24 synovial sites from 12 joints detected 100% of patients with synovitis and 91% of patients with PD signal. There was a highly significant correlation between the 44-joint count and index for synovitis and PD signal and the 12-joint count and index for synovitis and PD signal at baseline and 6 months (r = 0.84-0.90, P < 0.0005). The smallest detectable difference was lower than the mean change in simplified PDUS variables. CONCLUSION: A 12-joint PDUS assessment of RA joint inflammation may be a valid, feasible method for multicenter monitoring of therapeutic response to biologic agents.