Recently diagnosed axial spondyloarthritis: gender differences and factors related to delay in diagnosis

Sex differences in biomarkers and biologic mechanisms in psoriatic diseases and spondyloarthritis

Psoriasis and spondyloarthritis (SpA), including psoriatic arthritis (PsA), are immune-mediated inflammatory conditions that affect the skin and musculoskeletal system. Males and female patients with psoriatic disease and SpA exhibit differences in clinical presentation, disease progression, and treatment response. The underlying biological mechanisms driving these sex differences remain poorly understood. This review explores the current evidence on sex-related differences in biomarkers and biological pathways in psoriasis, PsA, and SpA. While no conclusive sex-specific biomarkers have been validated, this review highlights several sex-related differences in biomarkers and biological pathways, including differences in bone turnover markers, IL-23/IL-17 pathway activity, pro-inflammatory cytokines, and cardio-metabolic profiles that may partially contribute to the clinical differences observed between male and female patients. Sex hormones may contribute to the altered bone metabolism and immune regulation in females. To effectively identify and validate sex-specific biomarkers, there is a need to prioritize sex as a biological variable in future research. Adopting such an approach should enhance more personalized therapeutic strategies and improve management for male and female patients with psoriatic disease and SpA.

Prevalence of Axial Spondyloarthritis in Young People With Chronic Low Back Pain at a Hospital-Based Health Management Organization: A 10-Year Database Study

INTRODUCTION

There is scarce information on the prevalence of axial spondylarthritis (axSpA) using the Assessment of SpondyloArthritis International Society (ASAS) criteria and even less in Latin America. This study aimed to estimate the prevalence of axSpA by applying the ASAS 2009 criteria to a medical records review study of young people with chronic low back pain (LBP) at a university hospital-based health management organization.

METHODS

Electronic medical records from the Hospital Italiano de Buenos Aires health management organization were reviewed to estimate the prevalence of axSpA (radiographic axSpA [r-axSpA] and nonradiographic axSpA [nr-axSpA]) using the ASAS 2009 axSpA criteria in all patients with chronic LBP (≥3 months) aged <45 years at the first LBP appointment, observed between 2009 and 2019.

RESULTS

Among 795 young people with CLBP, the estimated prevalence of axSpA was 5.78% (r-axSpA, 2.76%; nr-axSpA, 3.02%). Ten of 46 patients (21.74%) with axSpA (all nr-axSpA) were undiagnosed, with an undiagnosed axSpA prevalence of 1.26%. The median interval between the first LBP appointment and diagnosis was 34.6 months for axSpA (58.7 vs. 23.1 months for r-axSpA vs. nr-axSpA). Previously diagnosed r-axSpA and nr-axSpA patients had comparable use of biological disease-modifying antirheumatic drugs (bDMARDs) (45% vs. 36%) and delays between nonsteroidal anti-inflammatory drug failure and bDMARD initiation (median, 2.76 vs. 2.66 months).

CONCLUSION

In our cohort of young persons with chronic LBP, the prevalence of axSpA was approximately 6%, with a high prevalence of undiagnosed axSpA, which could explain the low prevalence of axSpA reported in previous studies in Latin America.

A lower frequency of inflammatory back pain in male patients with ankylosing spondylitis compared with female patients

In routine rheumatology practice, we noticed that a significant number of male ankylosing spondylitis (AS) patients did not experience inflammatory back pain (IBP). Based on this observation, we aimed to investigate the prevalence of IBP in male AS patients and compare it to that in female patients. Patients with AS who fulfilled the modified New York criteria were subjected to a face-to-face interview with a standardized questionnaire that addressed the IBP components based on the Berlin criteria. The study also included 63 patients with chronic mechanical back pain (MBP). Erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) levels were measured, and Bath Ankylosing Spondylitis Disease Activity, Function, and Metrology Indexes (BASDAI, BASFI, and BASMI) were evaluated in patients with AS. There were 181 patients with AS (124 males, mean age 41.2 years; 57 females, mean age 44.6 years) and 63 patients with MBP (28 males, mean age 47.2 years; 35 females, mean age 43.5 years). The prevalence of IBP was found to be 87.7% in female and 66.1% in male patients with AS (p = 0.002). The specificity of the criteria was determined to be high both in females (85.7%) and males (89.2%). Female patients with AS had higher BASDAI levels than males (p = 0.048), but no difference was found in BASFI, BASMI, or serum CRP levels between genders. A considerable proportion of male patients with AS did not experience IBP, although they had similar CRP levels compared with females.

Sex Bias in Diagnostic Delay: Are Axial Spondyloarthritis and Ankylosing Spondylitis Still Phantom Diseases in Women? A Systematic Review and Meta-Analysis

Diagnostic delay (DD) is associated with poor radiological and quality of life outcomes in axial spondyloarthritis (ax-SpA) and ankylosing spondylitis (AS). The female (F) population is often misdiagnosed, as classification criteria were previously studied mostly in males (M). We conducted a systematic review to investigate (i) the difference in DD between the sexes, the impact of HLA*B27 and clinical and social factors (work and education) on this gap, and (ii) the possible influence of the year of publication (before and after the 2009 ASAS classification criteria), geographical region (Europe and Israel vs. extra-European countries), sample sources (mono-center vs. multi-center studies), and world bank (WB) economic class on DD in both sexes. We searched, in PubMed and Embase, studies that reported the mean or median DD or the statistical difference in DD between sexes, adding a manual search. Starting from 399 publications, we selected 26 studies (17 from PubMed and Embase, 9 from manual search) that were successively evaluated with the modified Newcastle-Ottawa Scale (m-NOS). The mean DD of 16 high-quality (m-NOS > 4/8) studies, pooled with random-effects meta-analysis, produces results higher in F (1.48, 95% CI 0.83-2.14, p < 0.0001) but with significant results at the second analysis only in articles published before the 2009 ASAS classification criteria (0.95, 95% CI 0.05-1.85, p < 0.0001) and in extra-European countries (3.16, 95% CI 2.11-4.22, p < 0.05). With limited evidence, some studies suggest that DD in F might be positively influenced by HLA*B27 positivity, peripheral involvement, and social factors.

Biomechanics in the onset and severity of spondyloarthritis: a force to be reckoned with

Increasing evidence suggests that there is a pivotal role for physical force (mechanotransduction) in the initiation and/or the perpetuation of spondyloarthritis; the review contained herein examines that evidence. Furthermore, we know that damage and inflammation can limit spinal mobility, but is there a cycle created by altered spinal mobility leading to additional damage and inflammation?Over the past several years, mechanotransduction, the mechanism by which mechanical perturbation influences gene expression and cellular behaviour, has recently gained popularity because of emerging data from both animal models and human studies of the pathogenesis of ankylosing spondylitis (AS). In this review, we provide evidence towards an appreciation of the unsolved paradigm of how biomechanical forces may play a role in the initiation and propagation of AS.

Sex-specific diagnostic efficacy of MRI in axial spondyloarthritis: challenging the 'One Size Fits All' notion

OBJECTIVES

Sex-specific differences in the presentation of axial spondyloarthritis (axSpA) may contribute to a diagnostic delay in women. The aim of this study was to investigate the diagnostic performance of MRI findings comparing men and women.

METHODS

Patients with back pain from six different prospective cohorts (n=1194) were screened for inclusion in this post hoc analysis. Two blinded readers scored the MRI data sets independently for the presence of ankylosis, erosion, sclerosis, fat metaplasia and bone marrow oedema. Χ2 tests were performed to compare lesion frequencies. Contingency tables were used to calculate markers for diagnostic performance, with clinical diagnosis as the standard of reference. The positive and negative likelihood ratios (LR+/LR-) were used to calculate the diagnostic OR (DOR) to assess the diagnostic performance.

RESULTS

After application of exclusion criteria, 526 patients (379 axSpA (136 women and 243 men) and 147 controls with chronic low back pain) were included. No major sex-specific differences in the diagnostic performance were shown for bone marrow oedema (DOR m: 3.0; f: 3.9). Fat metaplasia showed a better diagnostic performance in men (DOR 37.9) than in women (DOR 5.0). Lower specificity was seen in women for erosions (77% vs 87%), sclerosis (44% vs 66%), fat metaplasia (87% vs 96%).

CONCLUSION

The diagnostic performance of structural MRI markers is substantially lower in female patients with axSpA; active inflammatory lesions show comparable performance in both sexes, while still overall inferior to structural markers. This leads to a comparably higher risk of false positive findings in women.

The Impact of Spondyloarthritis on Health-Related Quality of Life and Healthcare Resource Utilization in Saudi Arabia: A Narrative Review and Directions for Future Research

Spondylarthritis (SpA) is an umbrella term that encompasses a wide range of rheumatological disorders. Several studies demonstrated that SpA is associated with increased healthcare resource utilization (HCRU) and a lower health-related quality of life (HRQoL). This review aimed to summarize the current literature regarding the multidimensional impact of SpA on HRQoL and HCRU in Saudi Arabia and explore the correlation of the extent of severity of SpA with HRQoL and HCRU. Although the prevalence of SpA varies across different populations and is correlated with HLA-B27 prevalence, the magnitude of SpA in the Saudi population has not been extensively evaluated. Few studies have investigated the impact of SpA on HRQoL and HCRU in Saudi Arabia and the Middle East. There is a need to study the cost-effectiveness of various SpA treatment strategies, including biologic disease-modifying anti-rheumatic drugs (bDMARDs), to prioritize healthcare spending in the Saudi healthcare system. Data on SpA in Saudi Arabia and the Middle East region are mainly based on expert views, with few population-based studies compared to other regions. Therefore, there is an imperative need to develop high-quality, national-level epidemiological studies that assess the following: (1) more accurate estimates of the current prevalence of SpA in Saudi Arabia, including the prevalence of axial SpA and psoriatic arthritis; (2) the phenotypes/clinical characteristics of SpA, including disease severity and extra-articular involvement; (3) the impact of SpA on the HRQoL of the patients and the factors that can predict the extent of impaired HRQoL in such population, which can represent the first step in developing psychological interventions that should be personalized to this patient population; (4) the impact of implementing formal assessment of disease activity on the management of the patients and, subsequently, their HRQoL; and (5) the HCRU and costs for patients with SpA, and how treatment patterns can affect this cost.

Impact of sex and gender on axSpA diagnosis and outcomes

Axial spondyloarthritis (axSpA) was historically considered a disease of men, largely due to the recognition of a more severe, progressive phenotype, ankylosing spondylitis (AS; or radiographic axSpA, r-axSpA) aiding the clinical diagnosis [1,2]. Data demonstrating the near equal prevalence of axSpA in women only started to emerge in the last decades, highlighting intrinsic differences in disease phenotype, and clinical and imaging characteristics between sexes, which partly explain the issue of underdiagnosis in women. Similar to the evolving understanding of spondyloarthritis and the diseases that term describes, the concepts of gender and sex also warrant further clarification to accurately assess their potential role in disease pathophysiology and phenotypic expression. This narrative review delves into the most recent evidence from the literature on the true prevalence of sex differences in axSpA, and the impact of sex and gender on diagnosis, disease characteristics and treatment response in this, still underserved, chronic disease.

Burden of disease and impact on quality of life in chronic back pain - a comparative cross-sectional study of 150 axial spondyloarthritis and 150 orthopedic back pain patients

Objective

Chronic back pain (CBP) constitutes one of the most common complaints in primary care and a leading cause of disability worldwide. CBP may be of mechanical or inflammatory character and may lead to functional impairment and reduced quality of life. In this study, we aimed to assess and compare burden of disease, functional capacity, quality of life and depressive symptoms in axial spondyloarthritis (axSpA) patients with orthopedic chronic back pain patients (OBP). We further aimed to identify factors associated with quality of life.

Methods

Cross-sectional survey of a cohort of 300 CBP patients including 150 patients from a University Hospital Orthopedic Back Pain Outpatient Clinic with OBP and 150 patients with confirmed axSpA from a University Hospital Rheumatology Outpatient Clinic. Questionnaire-based assessment of pain character (Inflammatory Back Pain, MAIL-Scale), functional status (FFbH, BASFI), quality of life (WHOQOL-Bref) and depressive symptoms (Phq9) and retrospective medical chart analysis.

Results

Both, OBP and axSpA patients reported on average intermediate pain levels of mostly mixed pain character. Both groups demonstrated a reduced health-related quality of life and the presence of depressive symptoms. However, axSpA patients reported a significantly better subjective quality of life, more satisfaction with their health status and better functional capacity compared to OBP patients (all p < 0.001). In a multivariate regression model, depressive symptoms, mechanical back pain, pain level and age were negative predictors of subjective quality of life, whereas functional capacity was a positive predictor.

Conclusion

Chronic back pain was associated with a high morbidity and reduced quality of life regardless of pain character. We identified multiple factors associated with reduced quality of life. Awareness and addressing of these factors may help to overcome unmet needs and improve quality of life for these patients.

The International Map of Axial Spondyloarthritis Survey: A US Patient Perspective on Diagnosis and Burden of Disease

OBJECTIVE

Axial spondyloarthritis (axSpA) is a chronic inflammatory disease that causes inflammation in the axial skeleton, resulting in structural damage and disability. We aimed to understand the effect of axSpA on work activity, day-to-day function, mental health, relationships, and quality of life and to examine barriers to early diagnosis.

METHODS

A 30-minute quantitative US version of the International Map of Axial Spondyloarthritis survey was administered online to US patients aged 18 years and older with a diagnosis of axSpA who were under the care of a health care provider from July 22 to November 10, 2021. This analysis describes demographics, clinical characteristics, journey to axSpA diagnosis, and disease burden.

RESULTS

We surveyed 228 US patients with axSpA. Patients had a mean diagnostic delay of 8.8 years, with a greater delay in women versus men (11.2 vs. 5.2 years), and 64.5% reported being misdiagnosed before receiving an axSpA diagnosis. Most patients (78.9%) had active disease (Bath Ankylosing Spondylitis Disease Activity Index score ≥4), reported psychological distress (57.0%; General Health Questionnaire 12 score ≥3), and experienced a high degree of impairment (81.6%; Assessment of Spondyloarthritis International Society Health Index score ≥6). Overall, 47% of patients had a medium or high limitation in activities of daily living, and 46% were not employed at survey completion.

CONCLUSION

The majority of US patients with axSpA had active disease, reported psychological distress, and reported impaired function. US patients experienced a substantial delay in time to diagnosis of axSpA that was twice as long in women versus men.

Worse scores but similar patterns of disease activity: interpreting outcomes in women with axial spondyloarthropathy

OBJECTIVE

The aim of this study was to evaluate the impact of sex on disease activity in axial spondylitis (axSpA).

METHOD

Data were extracted from the Ankylosing Spondylitis Registry of Ireland (ASRI). In this cross-sectional study, patients were analysed on the basis of sex, with a series of comparison analyses performed.

RESULTS

Overall, 886 participants were enrolled in the ASRI [232 (26.2%) women, 644 (72.6%) men]. Females recorded significantly worse Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) (4.57 vs 3.83, p < 0.01) and Ankylosing Spondylitis Quality of Life questionnaire (ASQoL) (7.51 vs 6.12, p < 0.01) scores than males. There was a stronger correlation in the Bath Ankylosing Spondylitis Functional and Metrology Indices (BASFI and BASMI) in females (r_s = 0.619, p < 0.01) than in males (r_s = 0.572, p < 0.01). Analysis of factors in BASDAI revealed that the higher total scores in females compared to males were due not to any single component, but to worse scores in all six components of the BASDAI combined. Ranking of components by severity between sexes revealed identical ranking in four of the six components of the BASDAI.

CONCLUSIONS

Women with axSpA reported significantly worse disease activity, quality of life, and functional ability than men. However, the BASDAI capturedsimilar patterns of disease activity. Limitation of spinal mobility in women with axSpA corresponded to greater impairment in functional ability. Further evaluation of disease monitoring tools is required to ensure that disease activity is accurately captured in men and women with axSpA.

Age and Symptoms at Onset of Ankylosing Spondylitis in Japanese Patients

OBJECTIVE

To examine the age at onset and initial symptoms as clinical features of ankylosing spondylitis (AS) in Japanese patients.

METHODS

This retrospective study included 60 Japanese patients diagnosed with AS at our institute between January 2004 and June 2021. Initial symptoms were considered pain in axial joints and/or extra-axial joints. If a patient had initial symptoms at multiple sites, each site was counted. We assessed trends for the number of patients and sites of initial symptoms according to age at onset.

RESULTS

Mean age (± standard deviation) at onset was 28.9 (± 14.3) years. Approximately one-third of patients experienced onset before age 20. The back was the most common site of initial symptoms (36.7%), followed by the hip (26.7%), knee (15%), buttocks (15%), neck (10%), finger (6.7%), shoulder (3.3%), and others (including overlapping sites). Thirty-two (53.3%) and 25 (41.7%) patients had initial symptom only in axial joints and only in extra-axial joints, respectively. The proportion of patients with initial symptoms only in extra-axial joints significantly decreased with increasing age (p=0.024).

CONCLUSION

Sites of initial symptoms were frequently the back, hip, knee, and buttocks, and 41.7% had initial symptom only in extra-axial joints. Younger onset patients frequently had extra-axial involvement.

Factors Associated With Diagnostic Delay of Axial Spondyloarthritis in Colombian Patients

BACKGROUND/OBJECTIVE

The diagnostic delay of axial spondyloarthritis (axSpA) is globally reported to be between 3 and 11 years. Early diagnosis and treatment have long-term benefits for patients and the health care system. Several international studies have evaluated some factors associated with diagnostic delay, but there are no known studies in the Colombian population. This study assesses the factors associated with diagnostic delay of axSpA in a rheumatology center in Bogota, Colombia.

METHODS

This monocentric analytical cross-sectional study was done in a specialized rheumatology center. Patients who fulfilled the 2009 Assessment of Spondyloarthritis International Society (ASAS) classification criteria for axSpA were included. Information was obtained from medical records and a phone call. Bivariate and multivariate analyses were done to assess the associated factors with diagnostic delay.

RESULTS

One hundred one patients were included, 54 were women (53.5%). The median diagnostic delay was 2 years (interquartile range, 1-7). The bivariate analysis showed that a younger age at diagnosis (p = 0.042) and previous diagnosis of lumbar degenerative disease (p = 0.029) were associated with a longer diagnostic delay. The logistical regression showed that previous lumbar degenerative disc disease (odds ratio, 2.8; 95% confidence interval, 1.09-7.53) and fibromyalgia (odds ratio, 4.0; 95% confidence interval, 1.2-13.1) diagnosis were both associated with a longer diagnostic delay.

CONCLUSIONS

Factors associated with a longer diagnostic delay were previous diagnosis of lumbar degenerative disc disease and fibromyalgia. Additional studies are needed so that the reasons for diagnostic delay are understood and early diagnosis and management of axSpA are enabled.

Differentiating nonradiographic axial spondyloarthritis from its mimics: a narrative review

Background

Optimal treatment of nonradiographic axial spondyloarthritis depends on accurate and timely diagnosis of the underlying disease; however, patients present with common symptoms that, in the absence of radiographic changes, may confound diagnosis.

Methods and findings

In this narrative review, a PubMed literature search was conducted through January 2021, with no date limits, to identify English-language publications discussing classification of nonradiographic axial spondyloarthritis, with an emphasis on clinical features and presentation, differential diagnoses, and mimics of disease. This review describes the epidemiology, clinical features, and burden of disease of nonradiographic axial spondyloarthritis as it relates to the overall axial spondyloarthritis spectrum and discusses mimics and differential diagnoses of nonradiographic axial spondyloarthritis that should be considered when evaluating patients with suspected nonradiographic axial spondyloarthritis in clinical practice.

Conclusions

Recognition of clinical features of nonradiographic axial spondyloarthritis, along with an understanding of comorbid conditions such as fibromyalgia, allows for differentiation from its mimics. Appropriate diagnosis of nonradiographic axial spondyloarthritis is important for aggressive management of disease to reduce pain, avoid loss of function, and improve quality of life.

Diagnostic delay in axial spondyloarthritis: a systematic review

Identification of axial spondyloarthritis (axSpA) remains challenging, frequently resulting in a diagnostic delay for patients. Current benchmarks of delay are usually reported as mean data, which are typically skewed and therefore may be overestimating delay. Our aim was to determine the extent of median delay patients’ experience in receiving a diagnosis of axSpA and examine whether specific factors are associated with the presence of such delay. We conducted a systematic review across five literature databases (from inception to November 2021), with studies reporting the average time period of diagnostic delay in patients with axSpA being included. Any additional information examining associations between specific factors and delay were also extracted. A narrative synthesis was used to report the median range of diagnostic delay experienced by patients with axSpA and summarise which factors have a role in the delay. From an initial 11,995 articles, 69 reported an average time period of diagnostic delay, with 25 of these providing a median delay from symptom onset to diagnosis. Across these studies, delay ranged from 0.67 to 8 years, with over three-quarters reporting a median of between 2 years and 6 years. A third of all studies reported median delay data ranging from just 2 to 2.3 years. Of seven variables reported with sufficient frequency to evaluate, only ‘gender’ and ‘family history of axSpA’ had sufficient concordant data to draw any conclusion on their role, neither influenced the extent of the delay. Despite improvements in recent decades, patients with axSpA frequently experience years of diagnostic delay and this remains an extensive worldwide problem. This is further compounded by a mixed picture of the disease, patient and healthcare-related factors influencing delay.

Key points • Despite improvements in recent decades, patients with axSpA frequently experience years of diagnostic delay. • Median diagnostic delay typically ranges from 2 to 6 years globally. • Neither ‘gender’ nor ‘family history of axSpA’ influenced the extent of diagnostic delay experienced. • Diagnostic delay based on mean, rather than median, data influences the interpretation of the delay time period and consistently reports a longer delay period.

Fibromyalgia in Axial Spondyloarthritis: A Meta-analysis

OBJECTIVES

This study aimed to compare the demographic characteristics, disease activity, functional status, and quality of life between patients with axial spondyloarthritis and fibromyalgia and patients with axial spondyloarthritis without fibromyalgia.

METHODS

We searched MEDLINE via PubMed, Cochrane, Scopus, and Embase databases, from the earliest available indexing date to March 30, 2019, for comparative studies evaluating fibromyalgia in patients with axial spondyloarthritis. Two authors extracted data independently, and all discrepancies were resolved through consensus.

RESULTS

Seven comparative studies were identified. No statistically significant differences were observed in terms of age, levels of inflammatory markers, and prevalence of extra-articular manifestations such as uveitis, psoriasis, and inflammatory bowel disease between patients with Axial spondyloarthritis fibromyalgia and those without it. Sex ratios (female to male) were approximately 3:2 and 1:3 in patients with and without fibromyalgia, respectively. The ratios concerning human leukocyte antigen B27-positive patients with and without fibromyalgia were 45.1% and 65.6%, respectively. Patients with fibromyalgia had significantly higher Bath Ankylosing Spondylitis Disease Activity Index, Bath Ankylosing Spondylitis Functional Index, and Ankylosing Spondylitis Quality of Life scores.

CONCLUSIONS

Our meta-analysis showed that patients with Axial spondyloarthritis fibromyalgia had considerably higher pain severity, disease activity, and worse quality of life than patients without fibromyalgia. The sex ratios (female to male) were approximately 3:2 and 1:3, and ratios for human leukocyte antigen B27-positive patients were 45.1% and 65.6% in patients with and without fibromyalgia, respectively. Further well-designed studies are needed to substantiate our results.

A Road Map of the Axial Spondyloarthritis Continuum

Axial spondyloarthritis (axSpA) is a chronic, immune-mediated inflammatory disease characterized by inflammatory low back pain, inflammation in peripheral joints and entheses, and other extra-articular or systemic manifestations. Although our understanding of the natural history of axSpA has been limited by incomplete knowledge of disease pathogenesis, axSpA is increasingly understood as a spectrum of axial, peripheral, and extra-articular inflammatory conditions that includes nonradiographic axSpA and radiographic axSpA, also known as ankylosing spondylitis. In this narrative review, we present a road map of this axSpA continuum, highlighting genetic risk factors for the development of axSpA, triggers of disease, and reasons for and implications of diagnostic delay. We present a detailed overview of the spectrum of axSpA clinical manifestations and highlight factors known to influence the risk of disease progression. Finally, we provide some expert commentary on the practical use of this road map to assist health care providers in the identification of axSpA in clinical practice.

Clinical Manifestations and Diagnosis of Axial Spondyloarthritis

BACKGROUND

Axial spondyloarthritis (axSpA) is a chronic, rheumatic disease characterized by inflammation of the sacroiliac joint, spine, and entheses. Axial spondyloarthritis affects up to 1.4% of adults in the United States and is associated with decreased quality of life, increased mortality, and substantial health care-related costs, imposing a high burden on patients, their caregivers, and society.

SUMMARY OF WORK

Diagnosing axSpA can be difficult. In this review, we seek to help rheumatologists in recognizing and diagnosing axSpA.

MAJOR CONCLUSIONS

A discussion of challenges associated with diagnosis is presented, including use and interpretation of imaging, reasons for diagnostic delays, differences in disease presentation by sex, and differential diagnoses of axSpA.

FUTURE RESEARCH DIRECTIONS

The early diagnosis of axSpA and advances in available therapeutic options have improved patient care and disease management, but delays in diagnosis and treatment remain common. Additional research and education are critical for recognizing diverse axSpA presentations and optimizing management early in the course of disease.

Educational needs and challenges in axial spondyloarthritis

PURPOSE OF REVIEW

Axial spondyloarthritis (axSpA) affects 0.5-1% of the population in many regions of the world. This review summarizes the challenges in medical education around axSpA with attention to evidence around delayed diagnosis, clinician familiarity with typical axSpA features, such as inflammatory back pain and adherence to accepted management principles.

RECENT FINDINGS

Clinicians who commonly manage patients with chronic back pain or other typical axSpA features are not consistently aware of the concept of inflammatory back pain and common extra-spinal manifestations. Further, clinicians may not be familiar with the nonradiographic spectrum of axSpA. Management of patients with possible axSpA does not consistently follow principles that would establish an axSpA diagnosis, and diagnosis of axSpA remains delayed by 6-7 years on average, with evidence suggesting management disparities on the basis of sex and race in some cases. Referral recommendations have increased the probability of axSpA diagnosis up to about 40% and, may complement educational efforts in axSpA.

SUMMARY

Educational efforts in axSpA should focus on providing front-line clinicians with a better understanding of inflammatory back pain, the nonradiographic form of axSpA, and accepted principles in axSpA management.

Gender-Specific Differences in Presentation and Management of Spinal Infection: A Single-Center Retrospective Study of 159 Cases

STUDY DESIGN

A retrospective single-center analysis of 159 cases.

OBJECTIVE

To investigate differences between male and female patients, as spinal infection (SI) represents a life-threatening condition and numerous factors may facilitate the course and outcome of SI, including patients' age and comorbidities, as well as gender. To date, no comparative data investigating sex differences in SI is available. Thus, the purpose of the present retrospective trial was to investigate differences between male and female patients.

METHODS

A total of 159 patients who were treated for a spinal infection between 2010 and 2016 at our department were included in the analysis. The patients were categorized into 2 groups based on gender. Evaluation included magnetic resonance imaging, laboratory values, clinical outcome, and conservative/operative management.

RESULTS

Male patients suffered from SI significantly more often than female patients (n = 101, 63.5% vs n = 58, 36.5%, P = .001). However, female patients were initially affected more severely, as infection parameters were significantly higher (P = .032) and vertebral destruction was more serious (P = .018). Furthermore, women suffered from intraoperative complications more often (P = .024) and received erythrocyte concentrates more frequently (P = .01). Nevertheless, mortality rates and outcome were comparable. Pain scales were significantly higher in female patients at 12-month follow-up (P = .042).

CONCLUSION

Although male patients show a higher incidence for SI, the course of disease and the management is more challenging in female patients. Nevertheless, outcome after 12 months is comparably good. Underlying mechanisms may include a better immune response and dissimilar effects of antibiotic treatment in women. Pain management in female patients is still unsatisfactory after 12 months.

Comparison of Men and Women With Axial Spondyloarthritis in the US-Based Corrona Psoriatic Arthritis/Spondyloarthritis Registry

OBJECTIVE

To compare patient characteristics and disease burden between men and women with axial spondyloarthritis (axSpA) in the US-based Corrona Psoriatic Arthritis/Spondyloarthritis (PsA/SpA) Registry.

METHODS

Patients aged ≥ 18 years with axSpA enrolled in the Corrona PsA/SpA Registry between March 2013 and November 2018 who were not concurrently diagnosed with PsA were included. Patient demographics, clinical characteristics, disease activity, patient-reported symptoms, work productivity, and treatment history at enrollment were compared between men and women, using t tests or Wilcoxon rank-sum tests for continuous variables and chi-square or Fisher exact tests for categorical variables.

RESULTS

Of 498 patients with axSpA and available sex information, 307 (61.6%) were men and 191 (38.4%) were women. Compared with men, women had higher disease activity as measured by Bath Ankylosing Spondylitis Disease Activity Index, Bath Ankylosing Spondylitis Functional Index, and physician global assessment, and had higher tender/swollen joint counts and enthesitis scores (all P ≤ 0.01). Women also had worse patient-reported symptoms (pain, fatigue, Health Assessment Questionnaire for the Spondyloarthropathies, and EuroQol visual analogue scale; all P < 0.05), had greater work and activity impairment, and were less likely to work full time than men. Prior conventional synthetic disease-modifying antirheumatic drug and prednisone use was more common in women than in men (both P < 0.05). Additionally, women were more likely to have diagnoses of depression and fibromyalgia (both P < 0.01).

CONCLUSION

In this US registry of patients with axSpA, women had higher overall disease burden and more peripheral manifestations than men. Improved awareness of sex differences in the presentation of axSpA may aid physicians in earlier identification and improved disease management.

Serum Oxytocin Levels in Patients with Ankylosing Spondylitis and Non-Radiographic Axial Spondyloarthritis and their Association with Disease Activity

Objectives Spondyloarthritis refers to a group of chronic inflammatory diseases that particularly involve the sacroiliac joints and spine but may also have an influence on extra-articular involvement in some patients. Oxytocin is a peptide hormone released from the hypothalamus and stored in the pituitary gland. It is known to have anti-inflammatory effects. The aim of this study was to investigate the serum levels of oxytocin and their potential association with disease activity and spinal mobility in patients with ankylosing spondylitis (AS) and non-radiographic axial spondyloarthritis (nrAxSpA).

Material and Methods Seventy-one patients with nrAxSpA, 38 patients with AS and 67 healthy control subjects were included in this study. Disease activity was assessed by the Bath Ankylosing Spondylitis Disease Activity Index, and spinal mobility by the Bath Ankylosing Spondylitis Metrologic Index. Laboratory examinations included complete blood count, ESR, CRP and oxytocin tests.

Results There was no significant difference in serum levels of oxytocin among the 3 groups (p=0.973). However, serum levels of oxytocin correlated negatively with both ESR (r=− 0.359, p=0.027), CRP (r=− 0.316, p=0.056) and BASDAI scores (r=− 0,448, p=0.005) in patients with AS. On the other hand, serum levels of oxytocin had a negative correlation only with ESR in patients with nrAxSpA (r=− 0.321 p=0.009).Conclusion This study lays the foundation for further studies that may aim to investigate how addition of oxytocin to the treatment regimen impacts on disease activity in patients with AS who exhibit particularly low levels of oxytocin during the active disease period.

Sex and gender differences in axial spondyloarthritis: myths and truths

Mounting evidence reveals evident sex differences in physiology, disease presentation and response to medication in axial SpA (axSpA). Unfortunately these data are often neglected in clinical practice and research. In this review, myths that still exist on diagnosis, disease manifestation and drug effectiveness were argued against data of the most recent literature. The aim is to increase awareness of sex differences in the clinical aspects of axSpA.

Non-radiographic versus radiographic axSpA: what's in a name?

Axial spondyloarthritis is a heterogeneous inflammatory condition with variable clinical presentations and outcomes. The complexity of its diagnosis and absence of biomarkers hamper the development of diagnostic criteria with the risk of misuse of the available classification criteria in clinical practice and its consequences. Axial spondyloarthritis should be regarded as a continuum in which some patients, but not all, will have a more severe phenotype characterized by progression into new bone formation and joint fusion. Growing understanding of the factors that might drive disease progression and treatment response will allow for better characterization of treatment options and outcome for each affected individual. The aim of this review is to update the current evidence of what is axial spondyloarthritis and to highlight the need to focus on the concept rather than its classification.

The Delay of Diagnosis in Spondyloarthropathy Patients in a Tertiary Hospital in Saudi Arabia

Objective

Seronegative spondyloarthropathies (SpA) are a group of rheumatological disorders that share the common feature of being rheumatoid factor negative. Inflammation of the sacroiliac joint is considered the hallmark of ankylosing spondylitis (AS). On the other hand, psoriatic arthritis (PsA) affects patients with psoriasis. It is characterized by asymmetrical oligoarticular arthritis. Involvement of the distal interphalangeal joint is a unique feature of PsA. Enteropathic arthritis (EnA) involves the presence of inflammatory arthropathy in patients with inflammatory bowel disease (IBD). These diseases are strongly associated with the HLA-B27 gene. Although they are significantly disabling, their diagnosis has been frequently delayed. Early diagnosis is associated with early treatment, and thus better disease outcomes. The aim of this study was to evaluate the diagnostic delay (DD), that is, the duration between onset of symptoms and diagnosis, of SpA patients and its relation to the demographic characteristics, disease activity, measured by ankylosing spondylitis disease activity score (ASDAS) and bath ankylosing spondylitis disease activity index (BASDAI) scores, and the HLA-B27 status of Saudi SpA patients.

Methods

The data of 94 patients who were diagnosed with SpA were collected from medical records and from them personally. The data included patient demographics, age at diagnosis, delay of diagnosis, in years, disease activity (BASDAI and ASDAS scores), HLA-B27 status and C-reactive protein levels (CRP). The data were analyzed using Statistical Package for the Social Sciences for Windows version 21.0 (SPSS Inc., Chicago, IL, USA).

Results

50% of patients were females. The mean DD was (mean ± SD) 4.98 ± 6.00 (range: 0-35). The average age of symptoms onset was 30.70 ± 11.30 (range: 8-59) and the average age at diagnosis was 35.65 ± 10.80 (range: 16-60). The mean BASDAI and ASDAS scores were 3.05 ± 2.21 and 2.29 ± 1.01, respectively. The majority of the patients had high disease activity (35.1 %). 25.0% were HLA-B27 positive. 83.7 % had normal CRP. There was no statistically significant difference between DD and gender, HLA-B27 status, ASDAS and BASDAI scores, and CRP. The DD was significantly higher in AS patients when compared to PsA (p-value= 0.048) and EnA patients (p-value < 0.0001). There was a statistically significant weak anticorrelation between DD and the age at symptoms onset in PsA patients (r-value= -0.39, p-value= 0.003). Age at diagnosis was statistically significantly higher in patients with PsA when compared to EnA. There was no correlation between DD and the disease activity in SpA patients.

Conclusion

The means of DD in AS, PsA, and EnA patients were 6.69 ± 5.83, 3.67 ± 6.42 and 2.00 ± 1.60, respectively. DD was greater in AS patients when compared to PsA and EnA patients. Early detection and referral to rheumatologists should be addressed, as early intervention is associated with favorable disease outcomes.

Chronic Pain and Assessment of Pain Sensitivity in Patients With Axial Spondyloarthritis: Results From the SPARTAKUS Cohort

OBJECTIVE

To study differences in pain reports between patients with ankylosing spondylitis (AS) and nonradiographic axial spondyloarthritis (nr-axSpA), and to assess how pain sensitivity measures associate with disease and health outcomes.

METHODS

Consecutive patients with axial SpA (axSpA) were enrolled in the population-based SPARTAKUS cohort (2015-2017) and classified as AS (n = 120) or nr-axSpA (n = 55). Pain was assessed with questionnaires (intensity/duration/distribution) and computerized cuff pressure algometry to measure pain sensitivity (pain threshold/pain tolerance/temporal summation of pain). Linear regression models were used to compare pain measures between patients with AS and nr-axSpA, and to assess associations between pain sensitivity measures and disease and health outcomes.

RESULTS

Of 175 patients with axSpA, 43% reported chronic widespread pain, with no significant differences in any questionnaire-derived or algometry-assessed pain measures between patients with AS and nr-axSpA. Lower pain tolerance was associated with longer symptom duration, worse Ankylosing Spondylitis Disease Activity Score using C-reactive protein (ASDAS-CRP), Bath Ankylosing Spondylitis Functional Index, and Bath Ankylosing Spondylitis Metrology Index (BASMI), more pain regions, unacceptable pain, worse Maastricht AS Enthesitis Score (MASES), fatigue, anxiety, and health-related quality of life. Further, lower pain threshold was associated with worse ASDAS-CRP and MASES, whereas higher temporal summation was associated with longer symptom duration, unacceptable pain, and worse BASMI.

CONCLUSION

Chronic pain is common in axSpA, with no observed differences in any pain measures between patients with AS and nr-axSpA. Further, higher pain sensitivity is associated with having worse disease and health outcomes. The results indicate that patients with AS and nr-axSpA, in line with most clinical characteristics, have a similar pain burden, and they highlight large unmet needs regarding individualized pain management, regardless of axSpA subgroup.

Differences between men and women with nonradiographic axial spondyloarthritis: clinical characteristics and treatment effectiveness in a real-life prospective cohort

BACKGROUND

Sex differences with regard to clinical manifestations and response to tumor necrosis factor inhibitors (TNFi) have been delineated for the radiographic form of axial spondyloarthritis (axSpA). More limited evidence for a differential effectiveness of treatment in genders exists for the nonradiographic disease state (nr-axSpA). The aim of the study was to compare demographics, clinical parameters, and response to TNFi in women versus men with nr-axSpA.

METHODS

We compared disease characteristics of 264 women and 231 men with nr-axSpA at inclusion in the prospective Swiss Clinical Quality Management Cohort. Response to a first TNFi was assessed in 85 women and 78 men without diagnosed co-morbid fibromyalgia. The primary outcome was the proportion of patients achieving the 40% improvement in the Assessment of SpondyloArthritis international Society criteria (ASAS40) at 1 year. Additional response outcomes were evaluated as secondary outcomes. Patients having discontinued TNFi were considered non-responders. Logistic regression analyses were adjusted for baseline differences, which might potentially mediate the effect of sex on treatment response.

RESULTS

Compared to men, women had a longer diagnostic delay, a higher level of perceived disease activity, and more enthesitis and were in a lower percentage HLA-B27 positive. An ASAS40 response was achieved by 17% of women and 38% of men (OR 0.34; 95% CI 0.12, 0.93; p = 0.02). A significantly lower response rate in women was confirmed in the adjusted analysis (OR 0.19; 95% CI 0.05, 0.62; p = 0.009) as well as for the other outcomes assessed.

CONCLUSION

Despite only few sex differences in patient characteristics in nr-axSpA, response rates to TNFi are significantly lower in women than in men.

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.

Understanding differences between men and women with axial spondyloarthritis

Axial spondyloarthritis (axSpA) is a chronic inflammatory immune-mediated disease resulting in inflammatory low back pain and other inflammatory manifestations in peripheral joints and entheses. AxSpA encompasses both ankylosing spondylitis (AS), in which patients present with definitive sacroiliitis visible on radiographic imaging, as well as nonradiographic axSpA (nr-axSpA), in which such changes may not be discernable. Emerging evidence suggests that women and men experience axSpA differently. Although the prevalence of AS is approximately 2- to 3- fold higher in men than in women, nr-axSpA occurs with roughly equal frequency in women and men. The goal of this review is to increase awareness of sex differences in axSpA by exploring the distinct manifestations of disease and disease characteristics in women, the overall clinical burden, recommendations for diagnosis, and potential treatment options. We summarize and contextualize the results of recent studies that illuminate sex differences in nr-axSpA and AS, including differences in disease manifestation and progression. It is important that sex differences in axSpA are understood and considered when diagnosing and treating the spectrum of axSpA, including AS and nr-axSpA.

Clinical, Economic, and Humanistic Burden Associated With Delayed Diagnosis of Axial Spondyloarthritis: A Systematic Review

INTRODUCTION

Few studies have evaluated the impact of delayed diagnosis of axial spondyloarthritis (axSpA) on the overall burden of disease. The objective of this review was to evaluate the available literature on the clinical, economic, and humanistic burden of delayed diagnosis in patients with axSpA.

METHODS

This systematic literature review was conducted and reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We searched the MEDLINE and Embase databases for English-language publications of original research articles (up to July 12, 2018) and conference abstracts (January 1, 2014, to July 12, 2018) reporting studies of adult patients with delayed diagnosis of axSpA associated with clinical, economic, or humanistic burden. Retrieved publications were screened for eligibility by two independent reviewers; discrepancies were resolved by a third independent reviewer. Data were extracted by one reviewer and validated by a second independent reviewer.

RESULTS

A total of 1391 publications were retrieved, of which 21 met the inclusion criteria and were included in the analysis. Of these, 15 reported data on clinical burden, nine on economic burden, and six on humanistic burden, with eight studies reporting a combination of clinical, economic, and/or humanistic burden. Patients with a delayed diagnosis of axSpA generally had higher disease activity, worse physical function, and more structural damage than those who received an earlier diagnosis. Patients with a delayed diagnosis also had a greater likelihood of work disability and higher direct and indirect healthcare costs than those who received an earlier diagnosis. Delayed diagnosis was associated with a greater likelihood for depression, negative psychological impacts, and worse quality of life.

CONCLUSIONS

Delayed axSpA diagnosis was associated with more functional impairment, higher healthcare costs, and worse quality of life, highlighting the importance of early recognition of axSpA to reduce extensive burden on patients and society. Plain language summary available for this article.

Risk factors for development and persistence of chronic widespread pain in spondyloarthritis: a population-based two-year follow-up study

Objective: To study chronic widespread pain (CWP) over time in patients with spondyloarthritis (SpA), and to identify risk factors for development and persistence of CWP.Methods: In this cohort study with baseline and 2.5 year follow-up postal surveys, patients with ankylosing spondylitis (AS) and undifferentiated spondyloarthritis (USpA) (47% women) answered questions regarding pain, and were categorized as no chronic pain (NCP), chronic regional pain (CRP), or CWP. For each risk factor candidate (disease duration, body mass index, smoking, and patient-reported outcome measures), logistic regression analyses with CWP as the main outcome were performed separately, together with a basic model including age, gender, and SpA subgroup.Results: Altogether, 644 patients could be categorized at both time-points, yielding similar prevalence estimates at baseline and follow-up, although 38% transitioned between pain groups. Risk factors (odds ratio; 95% confidence interval) for development of CWP included more pain regions (1.36; 1.20‒1.53), higher pain intensity (1.35; 1.20‒1.52), worse fatigue (1.25; 1.13‒1.38), and worse global health (1.35; 1.19‒1.54). Persistent CWP was reported by 72%. In addition to factors predicting development of CWP, higher age (1.02; 1.00‒1.04), female gender (1.82; 1.06‒3.10), and anxiety (1.07; 1.00-1.14) also predicted persistence.Conclusion: The prevalence of CWP remained high over time, but with individual transitions between the pain groups. The development and persistence of CWP were predicted by more pain and worse health, with the addition of female gender and higher age for persistent CWP. Special attention and treatment alternatives for patients with SpA and concomitant CWP are essential in the clinic.

Real-World Patient Experience on the Path to Diagnosis of Ankylosing Spondylitis

Introduction

We describe the journey to diagnosis of ankylosing spondylitis (AS) from the patient perspective and examine differences in this journey by sex.

Methods

US adults aged ≥ 18 years with a self-reported AS diagnosis were recruited online through CreakyJoints, a patient support community, and ArthritisPower, a patient research registry. Respondents completed a web-based survey on sociodemographics, disease burden, and diagnosis history. Results were stratified by sex and time to diagnosis using two-sample t tests and χ² tests, respectively, to observe differences across the groups; P < 0.05 was considered statistically significant.

Results

Among 235 respondents, 174 (74.0%) were female. Mean (SD) ages of female and male respondents were 48.6 (10.6) and 53.1 (10.3) years, respectively. From the time respondents began seeking medical attention, 87 were diagnosed within ≤ 1 year, 71 in 2–9 years, and 77 after ≥ 10 years. Symptoms that led respondents to seek treatment were back pain (73.2%) and joint pain (63.8%); fatigue and difficulty sleeping were more common among respondents with longer times to diagnosis. During the diagnosis process, men with AS tended to receive quicker AS diagnosis compared with women. Overall, commonly reported initial diagnoses among respondents with longer time to AS diagnosis included back problems and psychosomatic disorders. Significantly more women reported misdiagnoses of fibromyalgia (20.7 vs. 6.6%) and psychosomatic disorders (40.8 vs. 23.0%) compared with men.

Conclusions

Diagnosis delays and misdiagnoses were common among respondents with AS. Increasing awareness about AS among referring providers may minimize diagnosis delay.

Funding

Novartis Pharmaceuticals Corporation.

Plain Language Summary

Plain language summary available for this article.

Electronic Supplementary Material

The online version of this article (10.1007/s40744-019-0153-7) contains supplementary material, which is available to authorized users.

Determinants of diagnostic delay in axial spondyloarthritis: an analysis based on linked claims and patient-reported survey data

Objectives

The objective of this study was to assess the current diagnostic delay in axial SpA (axSpA) and to analyse factors associated with it.

Methods

A stratified sample of subjects with a diagnosis of axSpA (International Classification of Diseases, 10th Revision code M45) was drawn from health insurance data in Germany and was questioned on disease-related, lifestyle and socio-economic characteristics. The diagnostic delay was calculated as the time from back pain onset until a diagnosis of axSpA. A multivariable linear regression analysis was performed to explore factors associated with the diagnostic delay.

Results

Among 1677 patients with axSpA included in the analysis, the mean diagnostic delay was 5.7 years (median 2.3). Of those, 407 patients were diagnosed in 1996–2005 and 484 patients in 2006–2015. The mean diagnostic delay was not substantially different in both periods: 6.3 years (median 2.6) and 7.4 (2.7), respectively. Multivariable linear regression revealed that female sex [β = 1.85 (95% CI 1.06, 2.65)], negative HLA-B27 status [β = 3.61 (95% CI 2.07, 5.14)], presence of psoriasis [β = 1.40 (95% CI 0.08, 2.73)] and younger age at symptom onset [β = 1.91 (95% CI 1.53, 2.29)] were factors associated with a longer diagnostic delay.

Conclusion

The diagnostic delay in axSpA is still unacceptably long. Patients who are female, young at symptom onset, HLA-B27 negative or have psoriasis have a longer diagnostic delay. Specific referral strategies might be necessary in order to decrease the diagnostic delay in patients presenting with these characteristics.

Prevalence of chronic widespread pain in a population-based cohort of patients with spondyloarthritis - a cross-sectional study

Background

Chronic pain, regional or widespread, is a frequent and multidimensional symptom in arthritis. There is still limited information on chronic pain in spondyloarthritis, which is important to recognize for adequate diagnosis and treatment. Our objective was to study differences in prevalence of chronic widespread pain in two spondyloarthritis subgroups: ankylosing spondylitis (AS) and undifferentiated spondyloarthritis (USpA).

Methods

A population-based postal survey involving questions on the duration, distribution, and intensity of pain was answered by 940 patients with AS (ICD-10 M45.9) or USpA (ICD-10 M46.1-0, M46.8-9). The patients were categorized as having chronic widespread pain, chronic regional pain, or no chronic pain, and prevalence estimates for the pain groups were calculated, including age- and sex-adjusted prevalence.

Results

The prevalence of chronic widespread pain was 45.3% in AS vs. 49.3% in USpA, and that of chronic regional pain was 17.7% vs. 21.9% (p = 0.033). More women than men reported having chronic widespread pain (54.1% vs. 41.2%, p ≤ 0.001), while the sex distribution for chronic regional pain was equal. Reports of pain intensity were equal in AS and USpA, with no significant difference in pain intensity between women and men who had chronic regional pain or chronic widespread pain. In the multiple logistic regression analysis, chronic widespread pain was associated to female sex, being an ever-smoker, and having a higher body mass index, controlled for SpA subgroup and disease duration.

Conclusions

The prevalence of chronic widespread pain in patients with AS and USpA is high, and with a female predominance, but with no difference in pain intensity between women and men. Chronic pain can complicate the clinical evaluation in patients with SpA, and highlights the need for a thorough clinical examination, including evaluation of inflammation and an accurate pain analysis, to individualize non-pharmacological and pharmacological treatment decisions.

Gender Differences in Axial Spondyloarthritis: Women Are Not So Lucky

PURPOSE OF REVIEW

Ankylosing spondylitis (AS) was historically seen as a predominantly male disease. However, more recent data showed a more homogenous sex prevalence. Unfortunately, in many studies in axial spondyloarthritis (axSpA), the number of women included is low and the analyses are often not stratified for gender distribution. The purpose of this review is to aggregate the existing data on gender differences in axSpA in order to increase the awareness that female axSpA patients are still under-recognized.

RECENT FINDINGS

Several studies considering gender differences revealed that female axSpA patients had different disease manifestations due to different immunological, hormonal, and genetic responses. For instance, allelic frequencies of the AHNK-gene and tissue non-specific alkaline phosphatase (TNAP) haplotypes differed between men and women with ankylosing spondylitis (AS). In addition, different levels of tumor necrosis factor (TNF), interleukins IL-6, IL-17, and IL-18, were found between the two sexes. Furthermore, female patients show a higher diagnostic delay compared to males. Several studies indicate a higher frequency of extra-articular manifestations (EAM) in female axSpA patients, such as enthesitis, psoriasis, and inflammatory bowel disease (IBD), whereas acute anterior uveitis is more prevalent in male patients. Male AS patients more frequently show a higher Bath Ankylosing Spondylitis Radiology Index (BASRI) scores and modified Stoke Ankylosing Spondylitis Spine Scores (mSASSS) than females, which indicates that males have higher radiological damage and radiographic progression. However, disease activity (BASDAI) and quality of life (AsQol) scores are significantly higher in women, and more importantly, they have significantly lower response rates to treatment with TNF inhibitors (TNFi) and a significantly lower drug adherence. Despite the fact that men with axial SpA have a worse radiologic prognosis, women have a high disease burden, in part because they have a longer delay in diagnosis, higher disease activity, and significantly less responsiveness to treatment with TNFi.

Nonradiographic axial spondyloarthritis: clinical and therapeutic relevance

Current classification criteria for axial spondyloarthritis (axSpA) provide for the inclusion of patients with a wide range of presentations and manifestations. While not considered a formal subclassification, patients are often divided into radiographic or nonradiographic axSpA based on the presence or absence of radiographic sacroiliitis. This review will focus on nonradiographic axSpA and will discuss clinical manifestations of disease that distinguish, or in many cases do not distinguish, this entity from other individuals with axSpA. This review will also cover treatment paradigms for nonradiographic axSpA, particularly the use of biologic therapies, where current data suggest that nonradiographic disease should be managed largely the same as radiographic disease, or classical ankylosing spondylitis.

Evaluation and Management of the Patient With Suspected Inflammatory Spine Disease

Axial spondyloarthritis (AxSpA) is a chronic inflammatory rheumatic disease characterized by inflammatory back pain (IBP) that manifests in childhood, late adolescence, or early adulthood. Ankylosing spondylitis (AS) and nonradiographic AxSpA represent 2 ends of the AxSpA spectrum. Diagnosis can be challenging because patients develop IBP that may not be associated with radiographic changes in the sacroiliac joints. Patients early in the course of disease are estimated to have at least the same level of disease activity and pain as patients with established disease; thus, they could benefit substantially from earlier diagnosis. Although the recent use of magnetic resonance imaging and its inclusion in diagnostic criteria has enhanced the identification of early AxSpA, improvement in early diagnosis has not been consistently reported across all studies. Limited knowledge of the continuum of AxSpA disease manifestations and lack of recognition of IBP in primary practice may contribute to this. Implementing a referral strategy that identifies patients with IBP for additional testing and assessment may lead to better recognition of early signs and symptoms of AxSpA, thereby offering the potential for improved patient outcomes. This review presents an overview of the epidemiology, clinical characteristics, and burdens of AxSpA, followed by a case presentation outlining approaches to the evaluation and management of a patient with suspected inflammatory spine disease.

Understanding How the Diagnostic Delay of Spondyloarthritis Differs Between Women and Men: A Systematic Review and Metaanalysis

OBJECTIVE

To identify empirical evidence of diagnostic delay in spondyloarthritis (SpA), determine whether sex-related differences persist, and conduct an analysis from that perspective of the possible causes, including the influence of quality research, in this group of inflammatory rheumatic diseases.

METHODS

A systematic review was done of delay in diagnosis of SpA in MEDLINE and EMBASE and other sources. Study quality was determined in line with the Strengthening The Reporting of OBservational studies in Epidemiology (STROBE) statement. A metaanalysis of 13 papers reporting sex-disaggregated data was performed to evaluate sex-related differences in diagnostic delay. The global effect of diagnostic delay by sex was calculated using means difference (D) through a fixed effects model.

RESULTS

The review included 23,883 patients (32.3% women) from 42 papers. No significant differences between the sexes were detected for symptoms at disease onset or during evolution. However, the mean for delay in diagnosis of SpA showed sex-related differences, being 8.8 years (7.4-10.1) for women and 6.5 (5.6-7.4) for men (p = 0.01). Only 40% of papers had high quality. A metaanalysis included 12,073 participants (31.2% women). The mean global effect was D = 0.6 years (0.31-0.89), indicating that men were diagnosed 0.6 year (7 months) before women.

CONCLUSION

Delay in diagnosis of SpA persists, and is longer in women than in men. There are no significant sex-related differences in symptoms that could explain sex-related differences in diagnostic delay. Methodological and possible publication bias could result in sex-biased medical practice.

Fibromyalgia in Spondyloarthritis: Effect on Disease Activity Assessment in Clinical Practice

Objective.

Spondyloarthritis (SpA) is the second most frequent inflammatory rheumatic disease, characterized by spinal involvement, peripheral arthritis, or enthesitis with marked pain, stiffness, and fatigue. Fibromyalgia (FM) may be associated with SpA, and shares some common symptoms. We aimed to determine how FM influences assessment of SpA disease activity, which is mainly dependent on patient-based outcome measures such as the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) or the Ankylosing Spondylitis Disease Activity Score (ASDAS).

Methods.

This single-center cross-sectional study included consecutive patients with SpA according to the Assessment of SpondyloArthritis International Society criteria. FM was diagnosed according to the 1990 American College of Rheumatology criteria. Patient characteristics, BASDAI, ASDAS/C-reactive protein (CRP), Bath Ankylosing Spondylitis Functional Index, Bath Ankylosing Spondylitis Metrology Index, and the Medical Outcomes Study Short Form-36 questionnaire were recorded and compared.

Results.

The study included 103 patients with SpA; 81 with axial and 22 with peripheral forms. Eighteen patients presented with concomitant FM, of whom 12 had axial SpA and 6 peripheral SpA. Demographic characteristics did not differ except for sex, with a female predominance in the FM group that was more marked in peripheral forms. BASDAI was higher in patients with FM [median (IQR): 4.2 (4.2) vs 2.2 (3.1); p = 0.0068], whereas ASDAS-CRP was not significantly different [median (IQR): 2.7 (2) vs 2 (1.3); p = 0.1264]. Nevertheless, median ASDAS-CRP corresponded to high disease activity in patients with SpA or FM compared with moderate activity in non-FM patients.

Conclusion.

FM is a frequent comorbidity in patients with SpA, especially in peripheral forms. In patients with SpA-FM, disease activity may be overestimated when measured by BASDAI and to a lesser extent by ASDAS-CRP, and this overestimation could lead to inappropriate treatment escalation.

Identifying the symptom and functional domains in patients with fibromyalgia: results of a cross-sectional Internet-based survey in Italy

Objective

The aims of this cross-sectional study were to investigate the usefulness of using an Internet survey of patients with fibromyalgia in order to obtain information concerning symptoms and functionality and identify clusters of clinical features that can distinguish patient subsets.

Methods

An Internet website has been used to collect data. Fibromyalgia Impact Questionnaire Revised version, self-administered Fibromyalgia Activity Score, and Self-Administered Pain Scale were used as questionnaires. Hierarchical agglomerative clustering was applied to the data obtained in order to identify symptoms and functional-based subgroups.

Results

Three hundred and fifty-three patients completed the study (85.3% women). The highest scored items were those related to sleep quality, fatigue/energy, pain, stiffness, degree of tenderness, balance problems, and environmental sensitivity. A high proportion of patients reported pain in the neck (81.4%), upper back (70.1%), and lower back (83.2%). A three-cluster solution best fitted the data. The variables were significantly different (P<0.0001) among the three clusters: cluster 1 (117 patients) reflected the lowest average scores across all symptoms, cluster 3 (116 patients) the highest scores, and cluster 2 (120 patients) captured moderate symptom levels, with low depression and anxiety.

Conclusion

Three subgroups of fibromyalgia samples in a large cohort of patients have been identified by using an Internet survey. This approach could provide rationale to support the study of individualized clinical evaluation and may be used to identify optimal treatment strategies.

Spinal Mobility in Axial Spondyloarthritis: A Cross-Sectional Clinical Study

OBJECTIVE

Research concerning spinal mobility in axial spondyloarthritis (axSpA) has focused on ankylosing spondylitis (AS), and data on the clinical diagnosis of undifferentiated spondyloarthritis (USpA) are limited. The objective was to study differences in spinal mobility between axSpA subgroups AS and USpA, including gender differences.

METHODS

A total of 183 patients with axSpA from a rheumatology clinic were included in the study. The earliest recorded spinal mobility measures (cervical rotation/flexion/extension/lateral flexion, tragus-to-wall distance, vital capacity, chest expansion, thoracic flexion, thoracolumbar flexion, lateral spinal flexion, lumbar flexion and intermalleolar distance) were obtained by specialized physiotherapists. Differences between subgroups were analysed using analysis of covariance, controlled for gender and disease duration.

RESULTS

In the USpA group (n = 57), the mean [standard deviation (SD)] age was 41.6 (11.4) years, and disease duration was 13 (10.6) years, with 54% men. In the AS group (n = 126), the mean (SD) age was 48.4 (13.5) years, and disease duration 24.6 (13.3) years, with 77% men. Spinal mobility was less restricted in USpA versus AS patients (p ≤ 0.05), with a median (interquartile range) tragus-to-wall distance of 11 (10-12) cm versus 13 (11.3-18.5) cm; thoracolumbar flexion 9 (7-10) cm versus 6.5 (4-9) cm; lateral spinal flexion 29 (25-36) cm versus 21.3 (12-31) cm; lumbar flexion 4.5 (3.5-5.0) cm versus 3.5 (2.0-4.5) cm and intermalleolar distance 113 (102-121) cm versus 101 (86-114) cm. There were no differences between the subgroups in cervical mobility, vital capacity, chest expansion or thoracic flexion, and there were few gender differences, besides anthropometric measures.

CONCLUSION

Patients with USpA and AS had similar cervical and chest mobility, while thoracic and lumbar mobility were more severely restricted in AS. There were few gender differences in either subgroup. Further studies, to understand the full impact of USpA on spinal mobility, are needed. Copyright © 2016 John Wiley & Sons, Ltd.

Ankylosing spondylitis and risk of ischaemic heart disease: a population-based cohort study

OBJECTIVE

To investigate the incidence and risk of ischaemic heart disease (IHD) and acute myocardial infarction (AMI), including the role of non-steroidal anti-inflammatory drugs (NSAID), in patients with ankylosing spondylitis (AS) compared with population controls.

METHODS

All patients with newly diagnosed AS (n=3809) from the British Clinical Practice Research Datalink (1987-2012) were matched with up to seven persons without AS by year of birth, gender and practice (n=26 197). Incidence rate ratios (IRR) and HRs for development of IHD and AMI were calculated. Stepwise analyses were performed adjusting for age, gender, comorbidity and drug use, including NSAIDs.

RESULTS

At baseline, 4.3% of the patients had IHD and 1.8% had AMI compared with 3.4% and 1.4% of the controls, respectively. After exclusion of pre-existing IHD or AMI, the IRRs were 1.18 (95% CI 0.96 to 1.46) and 0.91 (95% CI 0.65 to 1.27) for IHD and AMI, respectively. Compared with controls, the age-gender adjusted HR for developing IHD was 1.20 (95% CI 0.97 to 1.48), and for AMI 0.91 (95% CI 0.65 to 1.28). In female patients, the risk of developing IHD was increased (HR 1.88, 95% CI 1.22 to 2.90), but after adjustment for all possible risk factors only a non-significant trend was found (HR 1.31, 95% CI 0.83 to 2.08). In particular, NSAID use explained this change (HR IHD adjusted for age-gender-NSAID use 1.57, 95% CI 0.99 to 2.48).

CONCLUSIONS

Female patients with AS had an increased age-adjusted risk of developing IHD, but after adjustment for NSAID use only a non-significant trend towards increased risk was found.

Delayed diagnosis of ankylosing spondylitis in a Japanese population

OBJECTIVES

This study was conducted to evaluate the period from symptom onset to diagnosis of ankylosing spondylitis (AS) in Japanese patients and to examine possible reasons for delayed diagnosis.

METHODS

Seventy-two consecutive patients with AS were studied. Diagnostic delay was defined as the gap between the first spondyloarthropathic symptom and diagnosis of AS according to the modified New York criteria.

RESULTS

The mean patient ages at disease onset and diagnosis were 25.6 ± 11.3 and 33.3 ± 13.2 years old, respectively, resulting in diagnostic delay of 6.7 years. The number of medical institutions to which patients were referred before diagnosis was 2.4, and orthopedic surgeons were most commonly visited (62%). Non-specific low back pain or lumbar spondylitis (33%) and degenerative arthritis (28%) were the primary diagnoses preceding that of AS. Absence of articular symptoms significantly correlated with diagnostic delay. The patients with disease onset on year 2000 or later had significantly shorter periods until diagnosis than those before 2000 (3.6 vs. 7.5 years).

CONCLUSIONS

The present study showed a marked diagnostic delay among Japanese patients with AS. Although it has been improved, continuing medical education focusing on inflammatory back pain in adolescent is required for early diagnosis of AS.

Gender-attributable differences in outcome of ankylosing spondylitis: long-term results from the Outcome in Ankylosing Spondylitis International Study

OBJECTIVES

To investigate gender-attributable differences regarding clinical outcome [disease activity, physical function and quality of life (QoL)] and radiographic damage in patients with AS over time.

METHODS

Data from the Outcome in AS International Study were used. Disease activity was assessed by the BASDAI, ASDAS and CRP; physical function by BASFI; QoL by the Short Form-36, Ankylosing Spondylitis Quality of Life (ASQoL) score and European Quality Of Life scale; and radiographic damage by the modified Stoke AS Spine Score (mSASSS). Cross-sectional comparative analyses were done at baseline. Next, separate models were created to assess gender-attributable differences on each outcome measure over time using time-adjusted generalized estimating equations.

RESULTS

A total of 216 patients [154 (72.3%) males, mean age 43.6 years (s.d. 12.7), symptom duration 20.5 years (s.d. 11.8), mean follow-up duration 8.3 years (s.d. 4.1)] were included. At baseline, male compared with female patients had lower self-reported disease activity (BASDAI 3.2 vs 3.9, P = 0.03) but more radiographic damage (mSASSS 13.8 vs 6.5, P = 0.02). No significant gender-attributable differences in other clinical parameters were found. In multivariable analysis, male gender was significantly associated with a better ASQoL (B = -1.18, 95% CI: -2.17, -0.20, P = 0.02), and in a separate model with a higher mSASSS over time (B = 8.24, 95% CI: 4.38, 12.09, P < 0.01).

CONCLUSION

In this prospective cohort study, no gender-attributable differences in disease activity or physical function over time were found. However, radiographic damage was more severe in males. Furthermore, males had a better QoL over time.

Diagnostic Delay in Ankylosing Spondylitis: Related Factors and Prognostic Outcomes

Objectives

This study aims to evaluate diagnostic delay, factors which are related to diagnostic delay, and the effect of diagnostic delay on prognostic outcomes in terms of spinal and hip mobility, functional status, disease activity, quality of life, cervical rotation, tragus to wall distance, and sacroiliitis severity in an Iranian population with ankylosing spondylitis (AS).

Patients and methods

One hundred and sixty three patients (129 males, 34 females; mean age 37.74±9.88 years; range 18 to 65 years) with AS who met modified New York 1984 criteria were enrolled consecutively in a cross sectional survey. The main outcome variable (diagnostic delay) was defined as the interval between appearance of first symptoms and correct diagnosis of AS. Enthesitis, negative human leukocyte antigen B27 (HLA- B27), and educational level were among the factors of which their relationship to diagnostic delay were evaluated. The prognostic outcomes were measured using Bath ankylosing spondylitis functional index, Bath ankylosing spondylitis disease activity index, AS quality of life, Bath ankylosing spondylitis metrology index, chest expansion, and radiographic sacroiliitis severity.

Results

Diagnostic delay was mean 7.88±7.17 years. Diagnostic delay was longer in patients with enthesitis (8.80±7.27) compared to patients without enthesitis (6.04±6.66) (p=0.007) and in HLA-B27 negative patients (10.10±7.44) compared to HLA-B27 positive patients (7.14±6.96) (p=0.013). Educational level was negatively correlated with diagnostic delay (p=0.002, r= -0.24). Diagnostic delay was correlated with Bath ankylosing spondylitis functional index (p=0.003, r=0.23), Bath ankylosing spondylitis disease activity index (p=0.026, r=0.18), AS quality of life (p=0.008, r=0.21), Bath ankylosing spondylitis metrology index (p<0.001, r=0.41), chest expansion (p<0.001, r= - 0.38), and sacroiliitis grading (p=0.042, r=0.16).

Conclusion

Negative HLA-B27, enthesitis, and low educational level are factors which affect diagnostic delay in AS. Individuals with enthesitis or low educational level should be evaluated accurately without causing delay in diagnosis since longer delay may lead to poorer prognostic outcomes.

Impact of gender, work, and clinical presentation on diagnostic delay in Italian patients with primary ankylosing spondylitis

The variability of demographic, social, genetic, and clinical factors might influence the time between the onset of symptoms and the diagnosis [diagnostic delay (DD)] of ankylosing spondylitis (AS) in different geographic areas. Different clinical manifestations in men and women affected by AS might indicate a possible role of gender in DD. The aim of the present study was to investigate the influence of demographic, social, genetic, and clinical factors on DD and the differences of DD between men and women related to the presence of different demographic, social, clinical, and genetic parameters in an Italian cohort of primary AS patients. A total of 135 Italian primary AS patients (45 female and 90 male, 27.9 ± 0.89 years old at onset) were studied. The DD, gender, education and work (manual or non-manual) levels, and type of first clinical presentation (inflammatory back pain, arthritis, enthesitis) at onset, family history of AS, and HLA B27 presence were analyzed. The DD (8.744 mean ±0.6869) was significantly higher in men (p = 0.0023), in axial presentation (p = 0.0021), and in manual work (even if with low significance, p = 0.047). The lower DD in women in comparison to that in men was likely related to higher education (p = 0.0045) and work (p = 0.0186) levels, peripheral involvement (p = 0.0009), and HLA B27 positivity (p = 0.0231). DD was higher in AS patients: male, employed in manual jobs, and with axial symptoms at onset. In men, DD seemed to be negatively influenced by lower level of education and work, axial clinical presentation, and HLA B27.

Pain in systemic inflammatory rheumatic diseases

The sometimes intense, persistent and disabling pain associated with rheumatoid arthritis (RA) and spondyloarthritis frequently has a multifactorial, simultaneously central and peripheral origin, and it may be due to currently active inflammation or joint damage and tissue destruction caused by a previous inflammatory condition. The symptoms of inflammatory pain symptoms can be partially relieved by non-steroidal anti-inflammatory drugs, but many patients continue to experience moderate pain due to alterations in central pain regulation mechanisms, as in the case of the chronic widespread pain (CWP) characterising fibromyalgia. The importance of distinguishing CWP from inflammatory pain is underlined by the fact that drugs such as tumour necrosis factor inhibitors are expensive, and direct costs are higher in patients with concomitant CWP than in those without. The management of pain requires a combination approach that includes pharmacological analgesia, and biological and non-biological treatments because, although joint replacement surgery can significantly improve RA-related pain, it may only be available to patients with the most severe advanced disease.

Gender differences in axial spondyloarthritis

Within the concept of axial spondyloarthritis (axSpA), relevant differences between men and women have been described for patients with the radiographic disease form [ankylosing spondylitis (AS)]. The subjective perception of disease activity (spinal and peripheral pain, fatigue, morning stiffness) has been shown to be higher in female than in male patients. Moreover, women experience more functional limitations and a lower quality of life, despite lower degrees of radiographic spinal damage. Peripheral clinical involvement (arthritis and enthesitis) is, additionally, more predominant in women. On the other hand, a higher level of objective signs of inflammation (C-reactive protein, erythrocyte sedimentation rate, magnetic resonance imaging of sacroiliac joints and spine) has been reported in men. Whether these differences might explain the better response to treatment with anti-tumor necrosis factor agents observed in male patients remains unclear. The underlying causes of the discrepancies are still unknown and genetic, environmental, cultural and/or societal factors may be involved. While AS is still more prevalent in men in a ratio of 2-3:1, the prevalence of males and females in patients with axSpA without radiographic sacroiliac damage is similar. Gender differences in this subgroup of patients have not been adequately addressed, and are particularly needed to further validate the Assessment of SpondyloArthritis international Society classification criteria.