Measuring impairments of functioning and health in patients with axial spondyloarthritis by using the ASAS Health Index and the Environmental Item Set: translation and cross-cultural adaptation into 15 languages

Performance of cut-offs of the ASAS Health Index to discriminate between treatment groups in patients with axial spondyloarthritis in the TICOSPA trial

OBJECTIVE

To test trial and longitudinal known group discrimination of thresholds of meaning for improvement and health states of the ASAS Health Index (ASAS HI) in patients with active axSpA treated in a randomized study.

METHODS

Data from baseline and week 48 from the tight-controlled, treat-to-target trial TICOSPA study were used. The performance of different thresholds to assess change or health states of the ASAS HI were evaluated between arms and against changes in patients' relevant outcomes and various external responder criteria. Analyses were performed by comparing the mean values t-tests or proportion of responders of continuous and dichotomous external criteria respectively. Trial discrimination of the ASAS HI thresholds were assessed by odds ratios and Phi coefficient in a large number of potential ASAS HI thresholds. Differences in health states in relevant external outcomes between ASAS HI responders and non-responders was assessed by comparing the best performing improvement and state thresholds by using t-tests and chi-square, as appropriate. Missing data on outcomes was handled by non-responder imputation (NRI).

RESULTS

All 160 patients had available ASAS HI data. Trial discrimination was larger for absolute ASAS HI change of ≥2.0, ≥2.5, and ≥3.0 points followed by ASAS HI 20 % improvement. Odds ratio ranged between 1.27 and 1.75 for absolute and between 1.0 and 1.64 for relative improvement outcomes. Longitudinal discrimination of ASAS HI improvement ≥30 % or ≥ 3.0 points had a larger reduction in patient global and disease activity and reached more often remission compared to patients with no significant improvement in global functioning. Patients who achieved ASAS HI ≤ 5.0 compared with patients who did not achieve such states were more likely to have ASAS partial remission, ASDAS inactive disease or ASDAS low activity at week 48.

CONCLUSIONS

The data-driven thresholds of the ASAS HI identified in a longitudinal observational setting perform well in the context of a randomized trial.

Clinical performance of the ASAS health index in chinese patients with ankylosing spondylitis and its influencing factors

OBJECTIVE

The aim of this study was to investigate the status of health-related quality of life in Chinese patients with ankylosing spondylitis (AS) and to analyze factors associated with the Assessment of SpondyloArthritis international Society Health Index (ASAS-HI) in AS and its relationship with disease activity and psychological status.

METHODS

A cross-sectional study of 484 patients with AS attending 10 hospitals in China from March 2021 to September 2023 was recruited. The ASAS-HI assessed general health and functional status; the Depression Anxiety Stress Scales (DASS-21) assessed psychological disorders such as anxiety, depression, and stress; and the Functional Assessment of Chronic illness Therapy-Fatigue Scale (FACIT-F) assessed patients' fatigue symptoms; the Ankylosing Spondylitis Disease Activity Score-C-Reactive Protein (ASDAS-CRP), Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), Bath Ankylosing Spondylitis Functional Index (BASFI), and Bath Ankylosing Spondylitis Measurement Index (BASMI) were used to assess patients' disease activity and functional impairment. The correlation between ASAS-HI and the ASDAS, poor psychological status, and fatigue symptoms was observed. Univariate and multivariate logistic regression analyses were used to explore the relevant influencing factors of ASAS-HI.

RESULTS

A total of 484 patients were included in this study of whom 162 were in poor health, 139 in moderate health, and 183 in good health. On univariate analysis, disease activity is an important factor affecting ASAS-HI. People with extremely high disease activity (ASDAS ≥ 3.5) had a 12 times elevated risk of having poor health status (OR = 12.53; P < 0.001). Other significant covariates included age ≥ 36 (OR = 1.58; P = 0.015), BMI ≥ 24 kg/m2 (OR = 2.93; P = 0.013), smoke (OR = 1.96; P = 0.002), BASFI (OR = 1.49; P < 0.001), BASMI (OR = 1.22; P < 0.001), fatigue (OR = 6.28; P < 0.001), and bad psychological conditions such as depression (OR = 10.86; P < 0.001), anxiety (OR = 3.88; P < 0.001), and stress (OR = 4.65; P < 0.001). The use of bMARDs is inversely associated with the appearance of adverse health status (OR = 0.54; P = 0.012). There was no significant relationship between HLA-B27 and sex. Multivariable logistic regression showed that higher disease activity (ASDAS ≥ 3.5) (OR = 5.14; P = 0.005), higher scores of BASMI (OR = 1.10; P = 0.009), self-reported depression (OR = 3.68; P = 0.007), and fatigue (OR = 2.76; P < 0.001) were factors associated with adverse health status.

CONCLUSION

The health status of AS patients is related to age, BMI, smoking, disease activity, poor psychological status, and fatigue and is influenced by a combination of multiple factors such as emotional state, economic level, pain, and dysfunction. Therefore, clinicians should pay attention to the early assessment of ASAS-HI in order to improve the prognosis of the disease. Key Points •Ankylosing spondylitis (AS) is a chronic inflammatory autoimmune disease with a long course and heavy disease burden, which greatly affects patients' quality of life. Therefore, this study aims to evaluate the health status of ankylosing spondylitis in the Chinese population and its influencing factors. •This is a multi-center cross-sectional study in China, which can better reflect the overall situation of the Chinese population.

Disease activity and widespread pain are main contributors to patient-reported global health in axial spondyloarthritis: an analysis of 6064 patients

Global health (GH) and health-related quality of life are patient priorities in axial spondyloarthritis (axSpA). Our objective was to assess the relative importance of disease-related factors including disease activity, and patient-related factors including comorbidities, to explain GH in axSpA. Post hoc cross-sectional analyses of 4 sets (COMOSPA, PERSPA, COMEDSPA, and DESIR) of patients fulfilling ASAS criteria for axSpA. GH was assessed through the ASAS Health Index (ASAS-HI) or the EuroQoL-5D-3L (EQ-5D). Disease-related factors included disease activity (ASDAS, psoriasis, arthritis, enthesitis, and CRP), disease duration, diagnostic delay, bamboo spine, and treatment. Non-disease-related factors included sociodemographic characteristics, comorbidities and chronic widespread pain. Multivariable logistic and linear regressions and partial variances (R2) were applied to identify independent determinants of GH. In 6064 patients (range 284-2756 across datasets), mean age ranged 38.9-45.8 years, 51-68% were male. GH was generally moderate: median ASAS-HI ranged 5.0-7.0. GH was explained by ASDAS (range of odds ratios, OR, 2.60-4.48) and chronic widespread pain (range of OR 2.19-8.39); other determinants included comorbidities and sociodemographic characteristics. Only 47-57% of the total variance in GH could be explained by the models; disease activity (partial variance, 16-26%) and chronic widespread pain (partial variance 12-15%) were the key contributing variables. A wide range of disease and non-disease-related variables usually collected in studies could only explain 47-57% of the variability in GH. Among these, disease activity and chronic widespread pain were most relevant and of similar magnitude of importance. These findings will be helpful for shared decision-making.

The ASAS Health Index and Environmental Factors Item Set: validity and reliability of the Swedish translations in Swedish patients with ankylosing spondylitis

OBJECTIVES

To translate the Assessment of SpondyloArthritis international Society (ASAS) Health Index (HI) Environmental Factors Item Set (EFIS) into Swedish and culturally adapt it for a Swedish context, and to assess the construct validity of the Swedish version of the ASAS HI and test-retest reliability in ASAS HI and EFIS in Swedish patients with ankylosing spondylitis (AS).

METHOD

Translation and cross-cultural adaptation of the EFIS were carried out according to a forward-backward procedure consisting of five steps. The construct validity of the ASAS HI was tested using Spearman correlation with standard health outcomes for axial spondyloarthritis (axSpA). Reliability was analysed by internal consistency with the Cronbach's alpha coefficient for ASAS HI, and test-retest reliability with intraclass correlation coefficients (ICCs) for ASAS HI and kappa agreement for the individual items of EFIS.

RESULTS

The translation of EFIS showed acceptable face and content validity. ASAS HI showed an acceptable internal consistency (Cronbach's alpha 0.79), and excellent test-retest reliability (ICC 0.87). Test-retest reliability for EFIS showed varied results, with kappa agreement for the individual items ranging from poor (-0.027) to good (0.80).

CONCLUSIONS

The Swedish version of ASAS HI proved to be valid and reliable and is recommended for assessing the impact of AS on global functioning and health. A Swedish version of EFIS has been produced and uploaded on the ASAS website. The EFIS proved to have acceptable face and content validity, and may contribute to the contextual interpretation of the ASAS HI.

Comparison of the ASAS Health Index in patients classified as radiographic axial spondyloarthritis (axSpA) or non-radiographic axSpA in the ASAS Health Index international validation study

OBJECTIVES

To determine if there were differences in the Assessment of SpondyloArthritis international Society Health Index (ASAS HI) scores between patients classified as radiographic axial spondyloarthritis (r-axSpA) and non-radiographic axSpA (nr-axSpA), and to identify factors associated with higher ASAS HI scores in both disease phenotypes.

METHODS

This study was an ancillary analysis of the ASAS HI international validation project performed in 23 countries. Patients were included if they were ≥18 years of age and diagnosed with axSpA. Univariable and multivariable analysis were performed to determine if ASAS HI scores differed between the axSpA phenotypes, and to identify other variables associated with ASAS HI scores. We also tested for potential interactions between the axSpA phenotype and significant variables identified through the multivariable regression.

RESULTS

A total of 976 patients were included, with 703 having r-axSpA and 273 nr-axSpA. Patients with r-axSpA reported higher (worse) ASAS HI scores compared with those with nr-axSpA (6.8 (4.4) vs 6.0 (4.0), p=0.02), but the axSpA phenotype was not associated with ASAS HI scores in the multivariable regression (β: -0.19, 95% CI: -0.56 to 0.19). Female gender, having worse physical function (Bath Ankylosing Spondylitis Functional Index), disease activity (Ankylosing Spondylitis Disease Activity Score) and anxiety and depressive symptoms (Hospital Anxiety and Depression Scale) were associated with higher ASAS HI scores. No interactions were found to be significant.

CONCLUSION

Overall health and functioning are similarly affected in patients with r-axSpA and nr-axSpA. Female patients, having worse physical function, disease activity, anxiety and depressive symptoms were independently associated with higher ASAS HI scores.

Translation and cross-cultural adaptation of the mSQUASH into Spanish

BACKGROUND

There is a lack of outcome measures for the assessment of physical activity in patients with axial spondyloarthritis (axSpA). For this matter, the modified Short QUestionnaire to Assess Health (mSQUASH) was developed and validated, originally in Dutch.

OBJECTIVE

To translate and cross-culturally adapt the mSQUASH into Spanish and to evaluate the equivalence of the translated version in patients with axSpA.

METHODS

The mSQUASH was translated following forward-backward procedure according to the protocol of Beaton. Two bi-lingual translators produced independent forward translations of the mSQUASH into Spanish, and the versions were harmonized in a consensual version. Another translator back translated the synthesized version into Dutch. A scientific committee reached consensus on discrepancies and developed a pre-final version of the questionnaire. The field test with cognitive debriefing involved 10 patients with axSpA with different gender, age, disease duration, educational level and working status.

RESULTS

The translation process of the mSQUASH was completed without major issues. The first translation needed several iterations due to small discrepancies in the wording. Back-translation was performed without difficulties, and the scientific committee agreed upon a final version of the questionnaire. Cognitive debriefing showed the Spanish questionnaire to be clear, relevant, understandable and comprehensive. The preliminary version was accepted with minor modifications.

CONCLUSIONS

The resulting Spanish version of the mSQUASH showed good linguistic and face validity according to the field test, revealing potential for use in clinical practice and research. In order to conclude the cross-cultural adaptation of the mSQUASH into Spanish, the next step is the assessment of psychometric properties of the Spanish version.

Evaluation of the relationship between blood cell markers and inflammation, disease activity, and general health status in ankylosing spondylitis

OBJECTIVE

The aim of this study was to assess the relation of systemic immune inflammation index, systemic inflammation response index, and systemic inflammation aggregate index with disease activity, functional status, and general health status in ankylosing spondylitis.

METHODS

Patients with ankylosing spondylitis and healthy volunteers were included in this cross-sectional study. Demographic data; disease activity measurements such as the Bath Ankylosing Spondylitis Disease Activity Index, the Ankylosing Spondylitis Disease Activity Score with C-reactive protein, and the Ankylosing Spondylitis Disease Activity Score with erythrocyte sedimentation rate; functional status such as the Bath Ankylosing Spondylitis Functional Index; and general health status such as the Assessment of Spondyloarthritis International Society Health Index of the patients were recorded. C-reactive protein, erythrocyte sedimentation rate, platelet to lymphocyte ratio, neutrophil to lymphocyte ratio, monocyte to lymphocyte ratio, systemic immune inflammation index, systemic inflammation response index, and systemic inflammation aggregate index values were recorded. Patients were grouped as active and remission according to the Bath Ankylosing Spondylitis Disease Activity Index score and as inactive-low and high-very high disease activity according to the Ankylosing Spondylitis Disease Activity Score. The correlation of laboratory parameters with disease-related parameters was tested.

RESULTS

The indexes were significantly higher in patients compared to controls (p<0.001, for platelet to lymphocyte ratio p=0.03). No significant differences existed in any blood cell-derived indexes among patient groups categorized by disease activity (p<0.05 for all). Systemic immune inflammation index was weakly correlated with Ankylosing Spondylitis Disease Activity Score with C-reactive protein (ρ=0.197 and p=0.049) and Ankylosing Spondylitis Disease Activity Score-erythrocyte sedimentation rate (ρ=0.201 and p=0.045). Systemic immune inflammation index was not correlated with Bath Ankylosing Spondylitis Disease Activity Index, Bath Ankylosing Spondylitis Functional Index, and Assessment of Spondyloarthritis International Society Health Index. No correlation was found between other indexes and disease-related variables. Platelet to lymphocyte ratio, systemic immune inflammation index, systemic inflammation response index, and systemic inflammation aggregate index showed a weak positive correlation with C-reactive protein and erythrocyte sedimentation rate (ρ=0.200-0.381).

CONCLUSION

Systemic immune inflammation index, systemic inflammation response index, and systemic inflammation aggregate index can be used to indicate systemic inflammatory burden in ankylosing spondylitis patients. However, these indexes are not effective in indicating patients' disease activity, general health status, and functional status.

Work participation in patients with axial spondyloarthritis: high prevalence of negative workplace experiences and long-term work impairment

INTRODUCTION

Axial spondyloarthritis (axSpA) is a chronic inflammatory disease that typically affects people in their second and third decades of life, which are important years for establishing a professional career. We aim to study outcomes of work participation (WP) and their associations with demographic and clinical confounders, in addition to prevalence of negative workplace experiences in axSpA.

METHODS

In total, 770 patients with axSpA participated in the multicentre, observational ATTENTUS-axSpA survey in Germany. Demographic information, clinical parameters and patient-related outcomes (including disease activity and function) with a focus on WP were prospectively recorded.

RESULTS

A high prevalence of negative workplace experiences was reported among the 770 patients analysed. Overall, 23.4% of patients were not employed and 6.5% received disability pensions. Current work cessation was prevalent in 120 patients, and 28 of those were out of work for 10 years or longer. Of the 590 currently employed patients, 31.9% reported absenteeism and 35.9% reported presenteeism for >1 month within the past year. Multivariate logistic regression identified low disease activity (Bath Ankylosing Spondylitis Disease Activity Index), better physical function (Bath Ankylosing Spondylitis Functional Index) and better global functioning (Assessment of SpondylAarthritis International Society-Health Index) as the main predictors for unimpaired WP (n=242). Importantly, biological treatment, disease duration, age, sex, education level and body mass index were not reliable predictors.

DISCUSSION

Despite improvements in pharmacological treatment options, we still observed substantially impaired WP in patients with axSpA. These data emphasise the high unmet need for targeted strategies to provide improved medical and social care.

Coping with rheumatic stressors (CORS) questionnaire: Spanish translation and cross-cultural adaptation

BACKGROUND

Rheumatic and Musculoskeletal Diseases (RMDs) substantially impact the lives of patients, with complex associations between disease severity and self-perceived health status. In this regard, the Coping with Rheumatic Stressors (CORS) questionnaire was developed to measure how patients with RMDs cope with stressors such as pain, limitations or dependency. The CORS is not currently available in Spanish, and therefore the adaptation of this instrument is needed.

OBJECTIVE

First, to cross-culturally adapt the CORS into Spanish for Spain. Secondly, to test the conceptual equivalence of the translated version in patients with axial spondyloarthritis (axSpA).

METHODS

A translation of the CORS into Spanish was performed adhering to the forward-backward procedure described by Beaton. Two translators produced independent forward translations of the item content, response options, and instructions of the CORS into Spanish. Both versions were harmonized in a consensual version. Another translator back-translated the synthesized version into Dutch. A scientific committee including all the translators, one methodologist and a rheumatologist, held a meeting and reached consensus on discrepancies to develop a final draft version of the Spanish CORS. Then, a field test with cognitive debriefing was conducted, involving a sample of 10 patients with axSpA.

RESULTS

The translation process of the CORS was completed after the discussion of some discrepancies throughout the process. The first translation was done without major complications. Back-translation presented some discrepancies. These led to minor modifications in the wording in one response option and 15 questionnaire items. The scientific committee agreed upon a final version of the questionnaire. Cognitive debriefing, led to minor modifications; for example, three respondents indicated that one of the statements in the instructions was syntactically complex ("indique cuán a menudo usted ha llevado a cabo dicho comportamiento") which led to its adjustment. The process indicated that the final CORS Spanish questionnaire was clear and understandable to all patients.

CONCLUSIONS

The Spanish version of the CORS showed good cross-cultural validity and good face validity according to the field test. Before the Spanish CORS is implemented, further validation is in progress to test the psychometric properties of the instrument in patients with axSpA.

Development of an environmental contextual factor item set relevant to global functioning and health in patients with axial Spondyloarthritis

OBJECTIVE

To describe the development of an Environmental contextual factors (EF) Item Set (EFIS) accompanying the disease specific Assessment of SpondyloArthritis international Society Health Index (ASAS HI).

METHOD

First, a candidate item pool was developed by linking items from existing questionnaires to 13 EF previously selected for the ICF/ASAS Core Set. Second, using data from two international surveys, which contained the EF item pool as well as the items from the ASAS HI, the number of EF-items was reduced based on the correlation between the item and the ASAS HI sum score combined with expert opinion. Third, the final English EFIS was translated into 15 languages and cross-culturally validated.

RESULTS

The initial item pool contained 53 EF addressing 4 ICF EF-chapters: products and technology (e1), support and relationship (e3), attitudes (e4) and health services (e5). Based on 1754 responses of axial spondyloarthritis patients in an international survey, 44 of 53 initial items were removed based on low correlations to the ASAS HI or redundancy combined with expert opinion. 9 items of the initial item pool (range correlation 0.21-0.49) form the final EFIS. The EFIS was translated into 15 languages and field tested in 24 countries.

CONCLUSIONS

An EFIS is available complementing the ASAS HI and helps to interpret the ASAS HI results by gaining an understanding of the interaction between a health condition and contextual factors. The EFIS emphasizes the importance of support and relationships, as well as attitudes of the patient and health services in relation to self-reported health.

The ASAS health index: a new era for health impact assessment in spondyloarthritis

The concept of spondyloarthritis (SpA) encompasses a series of entities that share clinical and imaging characteristics and a common genetic basis. These diseases can affect 0.20 to 1.6% of the general population, limiting functioning and affecting the quality of life of patients. Considering the patient perspective in the management of the disease and ensuring patients are sufficiently prepared to participate in decisionmaking is critical to treatment success as well as for optimal health outcomes. The overall picture of impairments, limitations, and restrictions in activities or social participation of patients with SpA is not adequately assessed in SpA-specific instruments. Therefore, it is quite relevant to measure the broader range of impairments that can affect SpA patients and integrate these into one measure of overall functioning in daily life. The Assessment of SpondyloArthritis international Society-Health Index (ASAS HI) is a recently introduced health instrument for evaluating SpA based on the International Classification of Functioning, Disability and Health, also known as ICF, that could cover a good part of the health metric needs in SpA. This review addresses its origins, its measurement properties, its use in routine clinical practice, as well as its prospects for future use.

Association of sleep disturbance with calcitonin, disease severity and health index among patients with ankylosing spondylitis

To investigate the association of sleep disturbance with calcium regulatory hormones, disease severity and health index among the patients with ankylosing spondylitis (AS).There were 104 AS patients enrolled in the cross-sectional study, and their sleep quality was recorded. Serum levels of calcium, parathyroid hormone, vitamin D3 and calcitonin were measured. We evaluated patient's disease activity, functional ability, patient's global assessment, physical mobility, radiographic damage and health index. Blood ESR and CRP levels were tested.Sleep quality was positively correlated with serum calcitonin levels (r = 0.260, P = .008). Bad sleep and advanced radiographic damage were found among the AS patients with detectable serum calcitonin levels (P < .05). Sleep quality was significantly correlated with disease duration, CRP, BASDAI, ASDAS-ESR, ASDAS-CRP, BASFI, BAS-G, BASMI and ASAS-HI among the AS patients (all P < .05). Female gender, longer disease duration, higher ASDAS-CRP and serum calcitonin levels (OR [95% CI] = 3.210 [1.012-10.181], P = .048) were independent factors associated with bad sleep. Inflammation, disease activity, functional ability, patient's global assessment and cervical rotation were useful in predicting bad sleep among the AS patients, and ASDAS-CRP was the best predictor (AUC = 0.772, P < .001).Serum calcitonin levels was elevated in the AS patients with bad sleep, and may participate in the pathophysiology of sleep disturbance. Bad sleep was associated with female gender, longer disease duration, higher inflammation, disease activity, functional impairment, mobility restriction, poor patient's global assessment and health index in AS. ASDAS-CRP was best in predicting bad sleep.

GlutenSpA trial: protocol for a randomised double-blind placebo-controlled trial of the impact of a gluten-free diet on quality of life in patients with axial spondyloarthritis

INTRODUCTION

Subclinical intestinal inflammation and gut dysbiosis have been reported in patients with spondyloarthritis (SpA). In common practice, rheumatologists are increasingly confronted with patients with inflammatory rheumatism who are on gluten-free diets (GFDs), despite the lack of reliable data from controlled studies. This study aims to determine the impact of a GFD on the quality of life of patients with axial SpA.

METHODS AND ANALYSIS

The GlutenSpA study is a 24-week, randomised, double-blinded, placebo-controlled, multicentre trial. Patients with axial SpA (n=200) will follow a 16-week GFD and be randomly assigned (1:1) to an experimental or control arm. In the experimental arm with receive at least 6 gluten-free breads per day + 200 g of gluten-free penne pasta per week + 6 rice flavour capsules per day. The control arm will receive at least 6 gluten-containing breads per day + 200 g of gluten-containing penne pasta per week + 6 vital gluten-containing capsules per day. The primary end-point is the variation in Assessment of SpondyloArthritis International Society-Health Index (ASAS-HI) questionnaire between week 16 and baseline. A second open-label period of 8 weeks will follow the intervention period, during which the patient will be free to decide whether they will follow the GFD. The secondary outcomes comprise several patient-reported outcomes (SpA activity (Bath Ankylosing Spondylitis Disease Activity Index)), fatigue (Functional Assessment of Chronic Illness Therapy), depression (Hospital Anxiety and Depression Scale), functional disability index (Bath Ankylosing Spondylitis Functional Index)), variations in body mass index and Homeostasis Model Assessment Index and variations in the abundance and type of bacterial species found in the gut microbiota for a subgroup of patients (n=40). The data will be analysed using the intention-to-treat principle.The regional ethics committee (CPP Nord-ouest IV) has approved the study (IDRCB 2018-A00309-46). The results of the trial will be submitted for publication in peer-reviewed journals. The authors have no relationship that may have influenced the submitted work.

TRIAL REGISTRATION NUMBER

NCT04274374.

The treatment journey for patients with axial spondyloarthritis in North Africa and the Middle East: From diagnosis to management

The management of axial spondyloarthritis (axSpA) is challenging worldwide, and the particular challenges shared by North Africa and the Middle East are mainly related to early diagnosis and standardized management. We believe there are several reasons for these challenges, including: (a) limited awareness of the disease manifestations and prevalence in the region among physicians; (b) the concept of nonradiographic axSpA, while accepted with some difficulty by the rheumatology community, may not be well understood by the referring primary care physicians; (c) access to, and training in magnetic resonance imaging varies greatly between countries in the North Africa and Middle East region, and this may have a large impact on early diagnosis; (d) country‐specific treatment guidelines are unavailable; and (e) economic and cultural factors influence patients’ attempts to seek and continue treatment. In this review, we will discuss the prevalence of axSpA in North Africa and the Middle East, as well as the challenges to diagnose and treat patients in this region. As rheumatologists practicing in North Africa and the Middle East, we also provide suggestions to assist physicians, other healthcare professionals, and researchers in facilitating early, accurate diagnosis and treatment of axSpA.

Clinical performance of ASAS Health Index in patients with ankylosing spondylitis and non-radiographic axial spondyloarthritis: real-world evidence from Multicenter Nationwide Registry

The Assessment of SpondyloArthritis international Society Health Index (ASAS HI) is used as a new instrument in measuring the function, disability and health of patients with spondyloarthritis (SpA). However, the real-world evidence of ASAS HI is very limited. In the present study, our objective is to evaluate the psychometric properties and performance of ASAS HI in the real-world setting as well as comparing ASAS HI with the current instruments to assess the construct validity and determine the cut-off points in patients with both ankylosing spondylitis (AS) and non-radiographic axial spondyloarthritis (nr-axSpA). A total of 991 patients with axSpA who fulfilled either the ASAS classification criteria for axial SpA (axSpA) or the Modified New York Criteria (mNY) for AS were recruited from the Biologic and targeted Synthetic antirheumatic drugs Registry (BioStaR) SpA. The construct validity of ASAS HI against the Bath Ankylosing Spondylitis Disease Activities Index (BASDAI) and Ankylosing Spondylitis Disease Activity Score-C-Reactive Protein (ASDAS-CRP) the Bath Ankylosing Spondylitis Functional index (BASFI) was performed. Using the receiver operating characteristic (ROC) curves analysis, the cut-off points were calculated. Of all the recruited patients, 851 (85.9%) were AS and 140 (14.1%) were nr-axSpA. The difference in the mean ASAS HI scores of the patients with AS and the ones with nr-axSpA were not statistically significant (6.12 ± 4.29 and 6.42 ± 4.86, respectively). The mean ASAS HI score was significantly higher in females and small city residents. The ASAS HI had a strong construct validity against ASDAS-CRP, BASDAI and BASFI. A cut-off point of ≤ 4 was determined to discriminate good and moderate, as well as ≥ 12 to discriminate moderate and poor health status. In conclusion, ASAS HI is a reliable instrument to evaluate health and functioning for both patients with AS and nr-axSpA in clinical practice.

Gender difference in ASAS HI among patients with ankylosing spondylitis

Objective

To assess the associations of the Assessment of Spondyloarthritis International Society Health Index (ASAS HI) with gender and other factors in patients with ankylosing spondylitis (AS).

Methods

From November 2017 to October 2018, we measured the Ankylosing Spondylitis Disease Activity Score (ASDAS), the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), the Bath Ankylosing Spondylitis Functional Index (BASFI), the modified Stoke Ankylosing Spondylitis Spinal Score (mSASSS) and the ASAS HI score for AS patients at the Taichung Veterans General Hospital. After adjusting for disease activity (ASDAS-erythrocyte sedimentation rate [ESR], ASDAS- C-reactive protein [CRP], BASDAI+ESR or BASDAI+CRP), mSASSS and other potential confounders including medications, comorbidities, and laboratory data, any associations between gender and the sum score of ASDAS HI were assessed using multiple linear regression analysis, as well as any associations between gender and an ASAS HI score >5 using multivariable logistic regression analysis.

Results

A total of 307 AS patients (62 [20.2%] females, mean age 46.4 years [S.D. 13.3], mean symptom duration 20.6 years [S.D. 12.1]) were included. Multiple linear regression analysis showed that the male gender was significantly associated with a lower ASAS HI (B = -1. 91, 95% confidence interval [CI], −2.82–−1.00, p <0.001). Multivariable logistic regression analysis revealed that males also had a lower risk of achieving scores of ASAS HI > 5 than females (odds ratio = 0.15, 95% CI, 0.07–0.36, p <0.001). Disease activity measures, including ASDAS-ESR, ASDAS-CRP and BASDAI, had positive correlations with ASAS HI.

Conclusion

This single-center, cross-sectional study revealed that a higher ASAS HI score was significantly associated with female gender and higher disease activity measures.

Validity, reliability, and factor structure of the Istanbul Low Back Pain Disability Index in axial spondyloarthritis

OBJECTIVE

To investigate the validation and reliability of Istanbul Low Back Pain Disability Index (ILBPDI) in axial spondyloarthritis (Ax-SpA).

METHODS

Patients with Ax-SpA according to The Assessment of SpondyloArthritis International Society criteria were recruited. The validation was assessed by face, content, and construct (convergent and divergent) validities, whereas the reliability was assessed by internal consistency and test-retest reliability. Factor analysis was performed. Convergent validity was assessed by correlations of ILBPDI with functional parameters (The Bath Ankylosing Spondylitis Functional Index, The Dougados Functional Index, and The Health Assessment Questionnaire). Divergent validity was assessed by correlations of ILBPDI with non-functional parameters.

RESULTS

Two hundred forty patients were recruited. Cognitive debriefing showed ILBPDI to be clear, relevant, and comprehensive. Cronbach's alpha coefficient was 0.953. The test-retest reliability was good with the intraclass correlation coefficient of 0.870. ILBPDI was represented by three-factor groups of activity: axial bending, sitting/rest, and standing activities. ILBPDI had good correlations with the functional parameters (rho changes between 0.809 and 0.580), and it had poor or non-significant correlations with the non-functional parameters (absolute rho changes between 0.669 and 0.001).

CONCLUSION

ILBPDI is a practical, accurate, and non-time-consuming scale which is valid and reliable to evaluate the functional disability in patients with Ax-SpA.

Measuring outcomes in ankylosing spondylitis: pearls and pitfalls

PURPOSE OF REVIEW

Patients with ankylosing spondylitis (AS) warrant a comprehensive clinical assessment because of the lack of biomarkers of disease activity, prognosis and response to biologic therapy. Multiple AS-related questionnaires have been developed to assess the disease status accurately, but feasibility remains a problem in clinical practice. The purpose of this review is to assess the pearls and pitfalls of AS-related outcome measures.

RECENT FINDINGS

Single-item questionnaires to measure pain, stiffness and fatigue in patients with AS are easily administrable but may lack a sufficient degree of responsiveness on an individual patient level. The Bath Ankylosing Disease Activity Index remains the gold standard for assessing disease activity in a routine practice, despite poor correlation with C-reactive protein (CRP) levels and MRI inflammation. The Ankylosing Spondylitis Disease Activity Score, a validated and highly discriminatory tool for assessing disease activity in AS, has been developed but lacks feasibility as erythrocytic sedimentation rate and CRP values are often not available during a clinic visit. RAPID-3 appears feasible to assess patients with AS quantitatively over time in busy clinical settings.

SUMMARY

The assessment of disease status in AS is complex and is impacted by multiple factors. The biggest challenge in AS is to incorporate the disease-specific indices into a routine practice. VIDEO ABSTRACT: http://links.lww.com/COR/A42.

Validity and reliability of the Assessment of Spondyloarthritis International Society Health Index in English-speaking patients with axial spondyloarthritis in Singapore

OBJECTIVES

To assess the validity and reliability of the Assessment of Spondyloarthritis International Society Health Index (ASAS HI) among patients with axial spondyloarthritis (axSpA) in Singapore.

METHODS

We collected data from English-speaking patients with axSpA seen at a dedicated axSpA clinic in a Singapore tertiary referral hospital from 2017 to 2018. Face validity of the English version of ASAS HI was assessed through cognitive debriefing interviews (CDIs). Structural validity was assessed with confirmatory factor analysis. Convergent construct validity was assessed with 12 a priori hypotheses about the magnitude and direction of correlations between the ASAS HI summary score and other patient-reported outcome measures. Internal consistency was assessed using Cronbach's alpha. Test-retest reliability was assessed by intraclass correlation coefficient (ICC). Measurement error was assessed by analyzing smallest detectable change (SDC).

RESULTS

Ten patients (age range 22-46 years, 50% male) participated in CDIs and face validity was supported. Among 108 patients (median age: 37 [21-77], 80.6% males), unidimensionality was confirmed (comparative fit index = 0.960, Tucker-Lewis Index = 0.952, root mean square error of approximation = 0.038, standardized root mean residuals = 0.068, model Chi-square test P = 0.1251) in the 17-item ASAS HI. The ASAS HI showed good internal consistency of 0.83 and excellent test-retest reliability (ICC = 0.95; 95% CI 0.91-0.98) when baseline was compared with week 2. SDC was 1.02. Convergent validity was supported as hypotheses were confirmed in 100% of the results.

CONCLUSIONS

This study supports the ASAS HI as a valid and reliable measure of health status for use in patients with axSpA in Singapore.

Development of one general and six country-specific algorithms to assess societal health utilities based on ASAS HI

Objective

Health utilities represent preference values that persons attach to health states. This study aims to develop one general and six country-specific algorithms to calculate societal preference values for health of patients with spondyloarthritis (SpA), as assessed by the disease-specific Assessment of SpondyloArthritis international Society Health Index (ASAS HI).

Methods

A survey was performed in random population samples from six European countries. In a best-worst choice experiment, subjects were asked to indicate repeatedly which of 4 random aspects of the 17-item ASAS HI was were most and least important. Bayesian analysis provided the relative importance of each of the 17 items. To rescale the relative importance scores on the absolute utility scale between 0 and 1, participants additionally completed two lead time trade-off experiments, one for 'severe SpA' and one for 'best health' without SpA. Six country-specific algorithms and one general algorithm were derived. The general algorithm was tested in 199 patients with axial SpA (axSpA).

Results

3039 subjects, mean age 47 years (SD 15) and 52% female completed the experiments. The population's health utility value for SpA varied between - 0.24 for 'worst' SpA (country range -0.35 to 0.03), and 0.88 for 'best' health (country range 0.81 to 0.90). Among 199 patients with axSpA, the mean utility was 0.36 (SD 0.30, range -0.24 to 0.88) and discriminated well between patients having high (Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) ≥ 4) or low (BASDAI < 4) disease activity (0.18 (SD 0.24) vs 0.51(SD 0.27), p<0.01).

Conclusion

One general and six country-specific algorithms are available to convert scores from the ASAS HI into disease-specific societal utility values.

A qualitative study of quality of life domains and subdomains relevant to patients with spondyloarthritis

AIMS

To identify quality of life (QoL) domains and subdomains relevant to patients with different spondyloarthritis (SpA) subtypes in Singapore, and to assess how identified QoL domains and subdomains map onto currently used patient-reported outcome measures (PROMs).

METHODS

Nine focus group discussions (FGDs), including two previously conducted FGDs from the Updating the Psoriatic Arthritis Core Domain Set Study, were conducted with patients with SpA in Singapore. The FGDs were organized by SpA subtype and language spoken. All FGDs were audio-taped, transcribed verbatim. After thematic analysis through open and axial coding, the domains were organized using the World Health Organization Quality of Life (WHOQOL) framework. Identified QoL domains and subdomains were mapped to currently used PROMs.

RESULTS

The nine FGDs included 51 patients. In total, 27 domains and 92 subdomains were identified and then organized within the 7 broad categories of the WHOQOL framework. Patients in Singapore were more concerned about "financial resources, " "work satisfaction" and "positive feelings" while less concerned about "freedom, physical safety and security" than patients in Western countries. "Home environment" and "work satisfaction" emerged as unique QoL domains relevant to patients with axial SpA (axSpA). PROMs for psoriatic arthritis (PsA) can capture both identified domains of PsA and axSpA.

CONCLUSIONS

A wide range of QoL domains and subdomains are relevant to SpA patients in Singapore, and there appears to be minimal differences in their relative importance between SpA subtypes. This study supports the development and validation of common QoL-specific PROMs for usage in SpA.

The Patient-Reported Outcomes Thermometer-5-Item Scale (5T-PROs): Validation of a New Tool for the Quick Assessment of Overall Health Status in Painful Rheumatic Diseases

Objective

To investigate the construct validity, reliability (internal consistency and retest reliability), and feasibility of the patient-reported outcomes thermometer–5-item scale (5T-PROs), a new tool to measure overall health status in patients with painful chronic rheumatic diseases such as rheumatoid arthritis (RA), psoriatic arthritis (PsA), axial spondyloarthritis (axialSpA), and fibromyalgia (FM).

Methods

Consecutive patients have been involved in this study. The following analyses were performed to establish the validity of the 5T-PROs: (1) principal component factor analysis was used to identify the presence of a relatively small number of underlying latent factors than can be used to represent relations among sets of many variables; (2) Cronbach's alpha was calculated as an indicator of internal consistency; and (3) Pearson product-moment correlations were conducted to assess the convergent validity. The 5T-PROs was also administered a second time (two weeks after the initial administration) to a subset of sample (n = 426) to allow for calculation of test-retest reliability. We used the intraclass correlation coefficient (ICC) as an estimate of test-retest reliability. Additionally, discriminant validity was tested using analysis of variance (ANOVA) with Bonferroni post hoc multiple comparisons, in different disease conditions. Feasibility was analyzed by the time taken in completing the 5T-PROs and the proportion of patients able to complete the 5 item.

Results

1,199 patients (572 with RA, 251 with axialSpA, 150 with PsA, and 226 with FM) were examined. The mean age was 55.7 (standard deviation: 13.1; range: 20 to 80) years. Factor analysis yielded two factors which accounted for 62.54% of the variance of the 5T-PROs. The first factor “Symptom Summary Score” (35.57% of the variance) revealed a good internal consistency (alpha = 0.88); the internal consistency of the second factor “Psychological Summary Score” (26.97% of the variance) was moderate (alpha = 0.69). The reliability of the whole instrument was good (alpha = 0.82). A very high correlation was obtained between Symptom Summary Score and SF-36 PCS and between pain thermometer intensity and SF-36 bodily pain. For all five items and summary scale scores of the SF-36, there was strong evidence that the mean rank of the scores differs significantly between the groups (Kruskal–Wallis tests, p < 0.001). Discriminant validity, assessed by comparing the 5T-PRO dimensions in patients with different states of disease activity, showed that the 5T-PROs show moderate association with the presence of comorbidities. It was also noted that it was inversely correlated (p=0.01) to years of formal education.

Conclusion

The 5T-PROs is easily administered, reliable and a valid instrument for evaluating the extensive multidimensional impact associated with chronic painful rheumatic conditions.

Validation and reliability of translation of the ASAS Health Index in a Colombian Spanish-speaking population with spondyloarthritis

To validate a Spanish language translation of the ASAS Heath-Index (ASAS-HI) testing, its reliability, construct validity, and responsiveness in Colombian patients with spondyloarthritis. Translation was done following a forward-backward procedure. Patients fulfilling the Assessment of Spondyloarthritis international Society (ASAS) criteria for either axial or peripheral spondyloarthritis (SpA) participated. Test-retest reliability was assessed by intra-class correlation coefficient (ICC) in patients without treatment changes. In patients who required a therapeutic intervention, responsiveness was assessed using the standardized response mean (SRM). Construct validity was evaluated by Spearman correlation. Internal consistency (Cronbach's α) and discriminative ability of the ASAS-HI were assessed. Fifty patients were included: 54% male, mean (SD) age 44.8 (13.1), symptom duration 15.8 (9.7) years, Bath Ankylosing Spondylitis Disease Index (BASDAI) 4.6 (2.2), Bath Ankylosing Spondylitis Functioning Index (BASFI) 4.7 (2.5), Ankylosing Spondylitis Disease Activity Score with C-Reactive Protein (ASDAS-CRP) 2.2 (1.0). Axial SpA was established in 44 patients (ankylosing spondylitis (AS) = 30, non-radiographic axial SpA (nr-axSpA) = 14) and peripheral SpA in 6 patients. The score of the ASAS-HI was 8.2 (5.1). The test-retest reliability was good with an ICC of 0.84. SRM was 2.58 (1.75-3.37) in 10 patients with any intervention and 2.94 (2.13-4.24) for 7 patients starting TNF blockers. Construct validity showed a good correlation between ASAS-HI and pain, BASDAI, BASFI, and Ankylosing Spondylitis Disease Activity Score (ASDAS) (r ≥ 0.60). A high internal consistency was found with a Cronbach's α of 0.91. ASAS-HI discriminated well between patients with different stages of disease activity (BASDAI and ASDAS). Those with higher disease activity had higher ASAS-HI scores. The Spanish language translation of the ASAS-HI has proven to be psychometrically valid for Colombian 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.

[Validation of the German translation of the ASAS health index : A questionnaire to assess functioning and health in patients with spondyloarthritis]

INTRODUCTION

The aim of this study was the validation of the German translation of the ASAS Health Index (ASAS HI), which measures functioning and health in patients with axial and peripheral spondyloarthritis (SpA).

METHOD

Patients with SpA who fulfilled the ASAS classification criteria for axial (axSpA) or peripheral SpA (pSpA) were included in this study. Constuct validity of the ASAS HI was tested by using Spearman's correlation coefficients. Reliability was analyzed by intraclass correlation coefficients (ICC) in patients with stable disease. In patients requiring an important therapeutic change because of unacceptable high disease activity, the sensitivity to change was analyzed using standardized response mean (SRM).

RESULTS

A total of 171 patients (57.9% male, age 44.4 ± 13.0 years) were included. The internal consistency was high with a Cronbach's alpha of 0.83. The reliability (n = 63) was good (ICC = 0.94; 95% confidence interval [CI] 0.90-0.96). The sensitivity to change of the ASAS HI was low for a relatively small number of cases (n = 33) with a SRM of -0.27 but showed a good ability to discriminate between various stages of disease activity and physical functioning.

DISCUSSION

We showed that the German translation of the ASAS HI provide good psychometric properties to assess functioning and health in patients with SpA. This reliable and sensitive to change questionnaire therefore enables the assessment of disease-specific global functioning and severity in patients with all forms of SpA.

Measurement properties of the ASAS Health Index: results of a global study in patients with axial and peripheral spondyloarthritis

OBJECTIVES

To evaluate construct validity, interpretability, reliability and responsiveness as well as determination of cut-off points for good and poor health within the original English version and the 18 translations of the disease-specific Assessment of Spondyloarthritis international Society Health Index (ASAS HI) in 23 countries worldwide in patients with spondyloarthritis (SpA).

METHODS

A representative sample of patients with SpA fulfilling the ASAS classification criteria for axial (axSpA) or peripheral SpA was used. The construct validity of the ASAS HI was tested using Spearman correlation with several standard health outcomes for axSpA. Test-retest reliability was assessed by intraclass correlation coefficients (ICCs) in patients with stable disease (interval 4-7 days). In patients who required an escalation of therapy because of high disease activity, responsiveness was tested after 2-24weeks using standardised response mean (SRM).

RESULTS

Among the 1548 patients, 64.9% were men, with a mean (SD) age 42.0 (13.4) years. Construct validity ranged from low (age: 0.10) to high (Bath AnkylosingSpondylitisFunctioning Index: 0.71). Internal consistency was high (Cronbach's α of 0.93). The reliability among 578 patients was good (ICC=0.87 (95% CI 0.84 to 0.89)). Responsiveness among 246 patients was moderate-large (SRM=-0.44 for non-steroidal anti-inflammatory drugs, -0.69 for conventional synthetic disease-modifying antirheumatic drug and -0.85 for tumour necrosis factor inhibitor). The smallest detectable change was 3.0. Values ≤5.0 have balanced specificity to distinguish good health as opposed to moderate health, and values ≥12.0 are specific to represent poor health as opposed to moderate health.

CONCLUSIONS

The ASAS HI proved to be valid, reliable and responsive. It can be used to evaluate the impact of SpA and its treatment on functioning and health. Furthermore, comparison of disease impact between populations is possible.