Validation of the Russian-language version of the ASAS Health Index
Authors: Akulova A. I. , Rebrov A. P. , Erdes Sh. , Gaydukova I. Z. 
Published: July 2019

The Assessment of Spondyloarthritis International Society (ASAS) Health Index (HI) is a comprehensive tool for quantifying the health of patients with axial (ax) spondyloarthritis (SpA), including ankylosing spondylitis (AS). ASAS HI was developed on the basis of the International Classification of Functioning, Disability, and Health (ICF). The questionnaire contains 17 questions, each of which is associated with a specific ICF pool (pain, emotions, sleep, sexual function, ambulation, self-care, and communication).

Objective: to study the psychometric properties of the Russian-language version of ASAS HI.

Subjects and methods. Examinations were made in 245 patients older than 18 years with axSpA or peripheral SpA, who met the ASAS criteria. The main psychometric properties of a questionnaire, such as validity, reliability (reproducibility), and sensitivity, were evaluated. SpA activity was assessed using the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) and the Ankylosing Spondylitis Disease Activity Score (ASDAS); the functional status of the patients was estimated by the Bath Ankylosing Spondylitis Functional Index (BASFI), and their spinal mobility was evaluated by the Bath Ankylosing Spondylitis Metrology Index (BASMI). The short-form 36 (SF-36) health questionnaire and the 5-dimensional EQ-5D version (EuroQoL) were used to assess quality of life in SpA patients. Patient satisfaction with their health status was estimated using the patient acceptable symptom state (PASS) index.

Results and discussion. The median age of the patients enrolled in the investigation was 39.5 [28.00; 48.00] years; disease duration – 102.5 [23.0; 196.5] months; there were 64.58% of men were and 78% of HLA-B27 positive patients. The median scores were for: BASDAI, 5.40 [3.20; 6.80]; ASDAS, 3.19 [2.55; 4.15]; BASFI, 5.60 [2.60; 7.50]; BASMI, 4.20 [3.00; 6.60]; ASAS HI, 9.00 [7.00; 12.00]; ASAS EF Items Set, 4.00 [3.00; 7.00]. There were statistically significant relationships between ASAS HI scores and C-reactive protein levels (Spearman correlation coefficient r=0.56), BASDAI (r=0.62), BASFI (r=0.67), ASDAS (r=0.38), BASMI (r=0.46), and patient's global assessment on a visual analogue scale (VAS) (r=0.49; p<0.05 for all measures). The ASAS EF Items Set scores correlated with the main clinical characteristics of the patients. There were statistically significant relationships between the ASAS HI/EF Items Set scores and the latter of eight SF-36 scales and the EQ-5D ques tionnaire. Statistically significant differences in ASAS HI scores were found in patients with positive and negative PASS indices (the median value of ASAS HI was 6.89 [3.00; 10.00] and 9.20 [7.00; 12.00], respectively; p=0.000086). Cronbach's internal consistency for ASAS HI was 0.988. There were statistically significant differences in ASAS HI scores before and after treatment (9 [7; 12] and 6 [3; 10], respectively; p=0.00025).

Conclusion. This study confirmed validity, reproducibility, and sensitivity to changes of the Russian-language version of ASAS HI for patients in the Russian Federation.