Background/Purpose: The aim of the study was to develop and validate a Spanish-language translation of the ASAS Heath Index (ASAS-HI) testing its reliability, construct validity and responsiveness in Colombian patients with SpA

Methods: Translation was done using a standardized operating procedure (forward-backward procedure). Patients fulfilling ASAS classification criteria for either axial (axSpA) or peripheral SpA (pSpA) participated. Test-retest reliability was assessed by intraclass correlation coefficient (ICC) in patients without treatment changes (stable disease state). In patients who required a therapeutic change because of high disease activity, responsiveness was assessed using a standardized response mean (SRM). Construct validity against other health outcomes was evaluated by Spearman correlation. Internal consistency (Cronbachs-α) and discriminative ability between ASAS-HI and ASDAS were assessed

Results: In total 50 patients were included: 54% male, mean (SD) age 44.8 (13.1) years, symptom duration 15.8 (9.7) years, BASDAI 4.6 (2.2), BASFI 4.7 (2.5), ASDAS-CRP 2.2 (1.0). The diagnosis of axSpA was established in 44 patients (AS =30, nr-axSpA =14) and pSpA in 6 patients. The total score of the ASAS-HI was 8.2 (5.1). The test-retest reliability (n=18) was good ICC: 0.84 (95%CI 0.71 to 0.93, p<0.001). Sensitivity to change was tested in 10 patients and SMR was 2.58 (1.75 to 3.37), and 2.94 (2.13 to 4.24) for those patients receiving TNFi (n=7). Construct validity showed a good correlation with clinical parameters (r≥0.60) for pain, BASDAI, BASFI, and ASDAS (Table 1). A high internal consistency was found with a Cronbachs-α of 0.91. The ASAS-HI discriminated well between patients with different stages of disease activity and function irrespective of the tool applied (BASDAI, BASFI and ASDAS) Table 2

Conclusion: The Spanish-language translation of the ASAS Health index was found relevant and comprehensive by patients with SpA. This version is available to evaluate the state of health and functioning in these patients and can be used in clinical practice   Table 1 Correlation coefficient (95%IC) between ASAS-HI and clinical characteristics

ASAS HI, The Assessment of Spondyloarthritis international Society Health Index; BASDAI, Bath ankylosing spondylitis activity disease indez; BASFI, Bath ankylosing spondylitis functional index; ASDAS, Ankylosing Spondylitis Disease Activity Score; NRS, numerical rating scale; EQ-5D, EuroQol standardized instrument; SF-36, Short form Health Survey 36 items; HAD-S, Hospital Anxiety and Depression Scale Table 2 Discriminant ability of ASAS-HI stratified by disease activity (mean±SD)