Fatigue in Ankylosing Spondylitis Is Associated With Psychological Factors and Brain Gray Matter

The status and correlation factors of fatigue in patients with ankylosing spondylitis (FACIT-F): a cross-sectional study based on the Chinese population

OBJECTIVE

To analyze the status and correlation factors of fatigue in patients with ankylosing spondylitis (AS), and provide a reference for improving the fatigue status of patients with AS.

METHOD

Using the AS-specific disease database of the Chinese Rheumatology Registration and Research Information Platform, patients with AS from 9 centers in China were selected as study subjects from March 2022 to September 2023. Functional Assessment of Chronic Illness Therapy Scale (FACIT-F) score, AS disease activity score-C-reactive protein (ASDAS-CRP), AS disease activity score-erythrocyte sedimentation rate (ASDAS-ESR), Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), Bath Ankylosing Spondylitis Function Index (BASFI), Bath Ankylosing Spondylitis Measurement Index (BASMI), Patient Global Assessment (PGA) score, night pain score, Depression Anxiety Stress Scale (DASS-21) and AS International Community Health Index Assessment (ASAS-HI) were observed. Human leukocyte antigen B27 (HLA-B27), C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) of the patients were detected. The data were analyzed by Spearman correlation and multiple linear regression.

RESULT

A total of 338 patients with AS were included in this study. Spearman correlation analysis results of 338 AS patients with fatigue showed that age, disease course, ASDAS-CRP, ASDAS-ESR, BASDAI, PGA, BASFI, BASMI, ASAS-HI and so on were the main correlation factors of fatigue (P < 0.05); Multiple linear regression analysis showed that BASDAI, ASAS-HI, depression and so on were independent predictors of fatigue in AS patients (P < 0.05). Spearman correlation analysis of no or very mild fatigue group showed that age, ASDAS-CRP, ASDAS-ESR, BASDAI, BASFI, ASAS-HI and so on were the main correlation factors of fatigue (P < 0.05); Multiple linear regression analysis showed that age, BASDAI, ASAS-HI were the independent predictor of fatigue in AS patients (P < 0.05). Spearman correlation analysis in the mild and moderate fatigue group showed that ASDAS-CRP, BASDAI, PGA, BASFI, ASAS-HI and so on were the main factors influencing fatigue (P < 0.05); Multiple linear regression analysis showed that BASDAI, depression and stress were independent predictors of fatigue in AS patients (P < 0.05).

CONCLUSION

In this study, fatigue was obvious in 37.9% of AS patients, and patients' fatigue levels were closely related to disease activity (ASDAS, BASDAI and PGA) and psychological factors (anxiety, depression and stress). At the same time, the higher the degree of fatigue, the more obvious the impact of disease activity and psychological factors on fatigue.

Prediction model for psychological disorders in ankylosing spondylitis patients based on multi-label classification

Objective

This study aims to develop a predictive model to assess the likelihood of psychological disorders in patients with ankylosing spondylitis (AS) and to explore the relationships between different factors and psychological disorders.

Methods

Patients were randomly divided into training and test sets in an 8:2 ratio. The Boruta algorithm was applied to select predictive factors, and a multi-label classification learning algorithm based on association rules (AR) was developed. Models were constructed using Random Forest (RF), K-Nearest Neighbor (KNN), RF-AR, and KNN-AR, and their performance was assessed through receiver operating characteristic (ROC) curves on the test set.

Results

A total of 513 AS patients were included, with 410 in the training set and 103 in the test set. The Boruta algorithm identified five key variables for the model: fatigue, ASAS-HI score, disease duration, disease activity, and BMI. The RF-AR model performed best, with an accuracy of 0.89 ± 0.06, recall of 0.78 ± 0.1, F1-score of 0.86 ± 0.08, Hamming loss of 0.05 ± 0.03, and a Jaccard similarity coefficient of 0.75 ± 0.12. The area under the curve (AUC) for the training set was 0.94.

Conclusion

This study developed a predictive model for assessing the risk of psychological disorders in AS patients. The model effectively captures the presence of psychological disorders, providing clinicians with valuable insights for adjusting treatment strategies.

Fatigue in Inflammatory Joint Diseases

Fatigue is a prevalent symptom in various rheumatic diseases, such as rheumatoid arthritis, psoriatic arthritis, and ankylosing spondylitis. It is characterised as a subjective, enduring feeling of generalised tiredness or exhaustion, impacting the patient's life quality and exacerbating disability. The fatigue nature is multifaceted, encompassing physiological, psychological, and social factors, and although the exact cause of inflammatory joint diseases is not fully understood, several factors are believed to contribute to its development. Despite high prevalence and importance, the symptom is often underestimated in clinical practice. Chronic inflammation, commonly associated with rheumatic diseases, has been proposed as a potential contributor to fatigue development. While current treatments effectively target inflammation and reduce disease activity, fatigue remains a persistent problem. Clinical evaluation of rheumatic diseases primarily relies on objective criteria, whereas fatigue, being a subjective symptom, is solely experienced and reported by the patient. Managing fatigue in inflammatory joint diseases involves a multifaceted approach. Identifying and comprehensively assessing the subjective components of fatigue in individual patients is crucial for effectively managing this symptom in everyday clinical practice.

Impairment in cognitive function in patients with axial spondyloarthritis and psoriatic arthritis

Spondyloarthritis may contribute to deficits in cognition. The objective of this study was to compare cognitive abilities in patients with axial spondyloarthritis (axSpA) or psoriatic arthritis (PsA) with matched reference groups. This investigator-initiated, cross-sectional, exploratory study of adults with axSpA or PsA was conducted at two German rheumatology centres (November 2018-September 2019). All data on patient and disease characteristics and cognitive abilities were collected at a single visit. Cognitive function was assessed by the previously validated Memory and Attention Test subscores of selective attention, episodic working memory, and episodic short-term memory and compared with subscores from healthy age-, sex-, and education-matched reference subjects. The mean patient age was 51.1 and 55.8 years in the axSpA (n = 101) and PsA (n = 117) groups, respectively, and mean symptom duration was 13.7 and 10.3 years. Compared with matched reference subjects, axSpA and PsA patients showed significant impairments in selective attention (mean difference of -6.5 and -4.5, respectively, on a 45-point scale; P < 0.001 for both) and no significant differences in episodic working memory. The PsA cohort, but not the axSpA cohort, had significantly better episodic short-term memory subscores compared with matched reference subjects (mean change of 2.0 on a 15-point scale; P < 0.001). Explorative subgroup analyses were unable to identify factors influencing cognitive changes, including disease activity, pain, and function, but may have been underpowered. We conclude that impairments in selective attention may impact the ability of axSpA and PsA patients to process information. These findings warrant additional studies, including longitudinal analyses, in patients with spondyloarthritis.

Identification of symptom clusters in patients with ankylosing spondylitis

Symptom cluster refers to a group of 3 or more related symptoms that occur together. Our objectives were to: (1) investigate the frequency, severity and gender difference of symptoms in patients with ankylosing spondylitis (AS); and (2) identify symptom clusters in AS patients. A cross-sectional questionnaire-based survey was conducted using the Patient Health Questionnaire Symptoms Group combined with self-designed variables. Demographic and symptom variables between male and female patients in terms of C-reactive protein (CRP) and human leukocyte antigen (HLA)-B27 status were analyzed with 2-tailed independent t test for continuous variables and Chi-square or Fisher's exact test for categorical variables. Symptom clusters were extracted and analyzed by principal component analysis. There were 122 AS patients included in the study. The most severe symptoms included severe back pain, extremity or joint pain, difficulty in breathing, constipation, intestine discomfort and diarrhea. Stomachache was more prevalent in male patients in which odds ratio was 4.60 (CI 1.59-12.97) (P = .006). Patients with HLA-B27 negativity or a higher CRP value were more likely to have dry mouth. Four symptom clusters were classified, which explained 58.4% of the total variation. They were named as the gastrointestinal-cardiac cluster, the fatigue-sleep disturbance cluster, the headache-chest pain cluster, and the mouth-eye cluster. The symptoms appeared to cluster into 4 groups in AS patients, which should be noticed in clinical care.

Exploring the Prevalence and Factors Associated With Fatigue in Axial Spondyloarthritis in an Asian Cohort in Singapore

Aim: To evaluate the prevalence of fatigue and the factors associated with fatigue among patients with axial spondyloarthritis (axSpA) within an Asian population.

Method: We used the baseline data from a clinic registry in a tertiary referral center. All patients fulfilled the 2009 Assessment of SpondyloArthritis international Society (ASAS) classification criteria for axSpA. Severe fatigue was defined as Bath Ankylosing Spondylitis Disease Activity Index-fatigue (BASDAI-fatigue) ≥5/10 and vitality domain of Short Form-36 Health Survey (SF-36 VT) ≤10th percentile of the general population.

Results: We included 262 consecutive patients with axSpA (79% men, 82.4% Chinese). The mean (standard deviation, SD) age and duration of disease were 41.7 (13.7) and 10.1 (8.3) years, respectively. 145 (55.3%) and 52 (31.1%) patients reported severe fatigue by the BASDAI-fatigue and SF-36 VT criteria, respectively. Patients with severe fatigue had worse scores across all disease activity assessments and disease impact measures compared to those without severe fatigue. Using principal component analyses, disease activity and impact were associated with BASDAI-fatigue, while disease activity and impact, and disease chronicity were associated with SF-36 VT. In the univariable analyses, all disease activity assessments and disease impact measures correlated with both BASDAI-fatigue and SF-36 VT. In the multivariable analyses, BASDAI-axial pain, BASFI, BAS-G, and ethnicity were associated with BASDAI-fatigue, while ASQoL and BASDAI-morning stiffness were associated with SF-36 VT.

Conclusion: Fatigue is prevalent amongst patients with axSpA in Asia and is associated with disease activity, disease impact as well as patient related factors.