Objectives We aimed to assess the prevalence of hip involvement and its characteristics, its correlates and its impact on patients’ quality of life (QoL) in Moroccan ankylosing spondylitis (AS).
Methods One-hundred-twenty patients with AS according to New York Classification criteria were consecutively recruited. To assess hip involvement were specified: presence of hip tenderness, range of passive and active motion, BASRI-Hip (≥hip involvement if ≥2) and functional impact (using the Lequesne index and the Harris hip Score) For all patients were collected: sociodemographic data; disease activity (evaluated by the Bath ankylosing spondylitis disease activity index (BASDAI)); functional disability (assessed by the Bath Ankylosing spondylitis functional index (BASFI)); spinal mobility (measured by the Bath Ankylosing Spondylitis Metrology Index (BASMI)) and radiographic damage (assessed by the Bath Ankylosing Spondylitis Radiologic Index (BASRI total score)). The erythrocyte sedimentation rate (ESR) and serum C-reactive protein (CRP) were determined. The quality of life (QoL) was measured by the generic instrument SF-36.
Results At the study inclusion, 75 patients (62.5%) had hip tenderness (70 (93.3% had bilateral hip tenderness)) with a mean pain intensity of 54.8±14.4. Sixty-eight patients (56.6%) had limited articular motion. In our data, 64 patients (53.3%) had radiographic hip involvement (59 patients (92.2%) had bilateral hip involvement) with a mean BASRI-Hip=3.1±1.2. Seven patients (5.8%) had a total articular replacement. The functional impact was high with a mean Lequesne score=13.9±6.3 and a mean Harris score=61.8±17.4 (49 patients (40.8%) have a Harris score ≥70 (indicating poor function)). Patients treated with biologic agents have best scores of Lequesne (p=0.011). Radiographic hip involvement was associated to an early age at onset (p=0.006), diagnosis delay (p=0.001), altered spinal mobility (p<0.001), high disease activity (BASDAI; p=0.025), severe functional disability (BASFI; p<0.001), structural damage (BASRI total score; p<0.001) and to altered physical and social domains of QoL (for all p≤0.001). Logistic regression analysis revealed a significant relationship between hip involvement and early age at onset, spinal mobility, functional disability, structural damage and disease activity (for all p≤0.01). In univariate and multivariate linear regression, the scores of Lequesne and Harris were significantly correlated with diagnosis delay, impaired spinal mobility, severe functional disability, radiographic damage; higher scores of BASRI-hip and altered physical and social domains of QoL (for all p≤0.05).
Conclusions Hip involvement is a major and highly prevalent issue in our AS patients that influences negatively patients’ QoL. Among our AS, there were significant associations between functional and radiographic hip scores and the impairment of spinal mobility, functional status and structural damage of AS. Taking into account the frequency and impact of hip involvement in the course of AS and considering the young age ate onset, the severity of functional impairment and the importance of diagnosis delay in Moroccan ankylosing spondylitis, as previously shown by several studies, it is necessary in our context to highlight the early recognition and management of AS especially with the advent of new treatments.
Disclosure of Interest None Declared