Changes in ankylosing spondylitis incidence, prevalence and time to diagnosis over two decades

The incidence and prevalence of ankylosing spondylitis in Thailand using ministry of public health database

Ankylosing spondylitis (AS), an inflammatory condition affecting axial and peripheral joints, exhibits varying prevalence worldwide. This study sought to ascertain AS incidence and prevalence in Thailand from 2017 to 2020. Utilizing national databases, individuals aged 18 and above with primary AS diagnoses (ICD-10 code M45) were identified. AS prevalence and incidence were calculated with 95% confidence intervals. The total number of AS patients was 13,292 patients in 2017. The prevalence of AS was 20.4 per 100,000 populations (95% CI 20.0-20.7) in 2017. The number of new AS cases, identified during 2018-2020, was 6784, 6805, and 6791 patients, respectively. The incidences of AS in 2018, 2019, and 2020 were comparable with the incidence of 10.4 (95% CI 10.1-10.6) per 100,000-person-years. The peak age at diagnosis was 50-59 years of age between 2018 and 2020. The number of female patients was 57.8%, 57.0%, and 57.6%, in 2018, 2019, and 2020, respectively. In conclusion, AS was relatively rare among Thais and comparable between males and females. The prevalence and incidence of AS in Thailand were identified by the Thailand Database Ministry of Public Health. The epidemiological profile of AS in Thailand might help to plan better care, workforce needs, and public health budgets.

Comparative surgical outcomes of navigated vs non-navigated posterior spinal fusions in ankylosing spondylitis patients

INTRODUCTION

Ankylosing Spondylitis (AS) patients with acute spinal fractures represent a challenge for practicing spine surgeons due to difficult operative anatomy and susceptibility to complications.

RESEARCH QUESTION

Does intraoperative CT-navigation improve outcomes in patients with ankylosing spondylitis undergoing surgery?

METHODS

A retrospective review was carried out at our centre from 05/2016-06/2021 to identify AS patients presenting with a traumatic spinal fracture, managed surgically with posterior spinal fusion (PSF). Cohorts were categorised and compared for outcomes based on those who underwent PSF with intraoperative CT-navigation versus those surgically managed with traditional intraoperative fluoroscopy.

RESULTS

37 AS patients were identified. 29/37 (78.4%) underwent PSF. Intraoperative navigation was used in 14 (48.3%) cases. Mean age of the entire cohort was 67.6 years. No difference existed between the navigated and non-navigated groups for mean levels fused (5.35 vs 5.07; p ​= ​0.31), length of operation (217.9mins vs 175.3mins; p ​= ​0.07), overall length-of-stay (12 days vs 21.9 days; p ​= ​0.16), patients requiring HDU (3/14 vs 5/15; p ​= ​0.09) or ICU (5/14 vs 9/15; p ​= ​0.10), postoperative neurological improvement (1/14 vs 1/15; p ​= ​0.48) or deterioration (1/14 vs 0/15; p ​= ​0.15), intraoperative complications (2/14 vs 3/15; p ​= ​0.34), postoperative complications 4/14 vs 4/15; p ​= ​0.46), revision surgeries (3/14 vs 1/15; p ​= ​0.16) and 30-day mortality (0/14 vs 0/15).

CONCLUSION

This is the first study that compares surgical outcomes of navigated vs non-navigated PSFs for AS patients with an acute spinal fracture. Although limited by its retrospective design and sample size, this study highlights the non-inferiority of intraoperative navigation as a surgical aid in a challenging cohort.

Therapeutic potential of single-nucleotide polymorphism-mediated IL6R inhibitors in ankylosing spondylitis treatment

Objective

Interleukin-6 (IL-6) is a multiple-effect cell factor implicated in the etiopathogenesis of several rheumatologic disorders. The blockade of the IL-6 pathway via IL6R inhibitors effectively treats these disorders. However, the clinical significance of the IL6R blockade for ankylosing spondylitis (AS) therapy remains controversial. With advances in genomics, increasing evidence has revealed the role of heritability in the etiology of disease, and Mendelian randomization (MR) analyses are being used more broadly to infer causation. Therefore, this MR study aims to evaluate the potential therapeutic utility of IL6R-targeted approaches in AS.

Methods

The C-reactive protein (CRP) level was used as an exposure factor, and rheumatoid arthritis (RA) was used as a positive control. As-related genome-wide association study (GWAS) data were used as the primary outcome of drug-targeted MR analyses to test the relation between IL6R blockers and AS. Inverse variance weighting (IVW) is the primary analytical approach. Various sensitivity tests were performed to check the robustness and trustworthiness of the causality estimation, including consistency, heterogeneity, and pleiotropy analyses. In addition, repeated analysis was conducted using different GWAS data related to exposures and outcomes to examine the results for stability.

Results

According to the IVW results, IL6R inhibitors significantly reduced the risk of AS in ukb-b-18194 (OR: 0.995, 95% CI 0.993-0.996, P = 5.12 × 10-08) and ukb-a-88 (OR: 0.994, 95% CI 0.993-0.996, P = 6.25 × 10-15). Moreover, repeated analyses were performed using different exposure-related GWAS data, yielding similar results, ukb-b-18194 (OR: 0.995, 95% CI 0.993-0.997, P = 1.25 × 10-06) and ukb-a-88 (OR: 0.995, 95% CI 0.994-0.997, P = 7.81 × 10-09). Heterogeneity analyses and pleiotropy analyses indicated no significant heterogeneity or pleiotropy.

Conclusion

This MR analysis result further validates that the IL-6 pathway may contribute to the pathogenesis of AS and that the inhibition of IL6R reduces the risk of AS. These findings may guide future studies and provide more favorable drug treatment options for people at high risk of AS.

"What Came First?" Population-Based Evaluation of Health Care Encounters for Depression and Anxiety Before and After Inflammatory Arthritis Diagnosis: Disentangling the Relationship Between Mental Health and Arthritis

OBJECTIVE

The study objective was to describe patterns of depression and anxiety health care use before and after diagnosis among patients with inflammatory arthritis (IA), namely, ankylosing spondylitis, psoriatic arthritis, and rheumatoid arthritis.

METHODS

We used population-based linked administrative health data from British Columbia, Canada, to build a cohort of individuals (≥18 years) with incident IA and individuals without IA ("IA-free controls") matched on age and sex. We computed the proportion of individuals with IA and controls who had one or more depression or one or more anxiety health care encounters and the use of one or more antidepressants or one or more anxiolytics in each yearly interval five years before and after IA diagnosis. We used multivariable logistic regression models to evaluate the association between IA status and aforementioned depression and anxiety health care use outcomes in each yearly interval.

RESULTS

A total of 80,238 individuals with IA (62.9% female; mean ± SD age 56.2 ± 16.7 years) and 80,238 IA-free controls (62.9% female; mean ± SD age 56.2 ± 16.6 years) were identified between January 1, 2001, and March 31, 2018. Individuals with IA had significantly increased odds of depression and anxiety health care encounters and dispensation of antidepressants and anxiolytics for each yearly interval before and after diagnosis. Adjusted odds ratios (ORs) were highest in the year immediately before (one or more depression visits: adjusted OR 1.61, 95% confidence interval [CI] 1.55-1.66; one or more anxiolytics: adjusted OR 1.71, 95% CI 1.66-1.77) or after (one or more antidepressants: adjusted OR 1.95, 95% CI 1.89-2.00) IA diagnosis.

CONCLUSION

Findings suggest a role for depression and anxiety in characterizing the IA prodrome period and generate hypotheses regarding overlapping biopsychosocial processes that link IA and mental health comorbidities.

Presence of periodontal disease and the incidence of inflammatory arthritides in the general population: data from the UK Biobank

OBJECTIVES

To investigate the association between periodontal disease and the development of inflammatory arthritides in the general population.

METHODS

In total, 489 125 participants from the UK Biobank without a previous history of RA, AS and PsA were enrolled. The primary outcome was the incidence of inflammatory arthritides, which was a composite of RA, AS and PsA according to the presence of periodontal disease based on self-reported oral health indicators. Multivariate Cox proportional hazard regression analyses using four different models were performed to assess the association between periodontal disease and inflammatory arthritides development.

RESULTS

In all, 86 905 and 402 220 individuals were categorized as with and without periodontal disease, respectively. Cox hazard analysis indicated that the presence of periodontal disease was an independent predictor of the occurrence of composite outcomes of inflammatory arthritides, which was also consistent for RA and AS. Significant associations were found to be consistent in the four Cox models and were replicated even when different criteria were used to define periodontal disease. Subgroup analyses indicated that periodontal disease was associated with an increased RA risk in those aged <60 years, and this risk was persistent for both male and female patients and for patients with seropositive/seronegative RA.

CONCLUSION

Self-reported periodontal disease is associated with inflammatory arthritides incidence in participants included in the UK Biobank, particularly for RA and AS. Higher clinical attention and optimal dental care in patients with signs of periodontal disease may be recommended for early disease detection and for reducing this risk.

Trends for opioid prescribing and the impact of the COVID-19 pandemic in patients with rheumatic and musculoskeletal diseases between 2006 and 2021

OBJECTIVE

To investigate opioid prescribing trends and assess the impact of the COVID-19 pandemic on opioid prescribing in rheumatic and musculoskeletal diseases (RMDs).

METHODS

Adult patients with RA, PsA, axial spondyloarthritis (AxSpA), SLE, OA and FM with opioid prescriptions between 1 January 2006 and 31 August 2021 without cancer in UK primary care were included. Age- and gender-standardized yearly rates of new and prevalent opioid users were calculated between 2006 and 2021. For prevalent users, monthly measures of mean morphine milligram equivalents (MME)/day were calculated between 2006 and 2021. To assess the impact of the pandemic, we fitted regression models to the monthly number of prevalent opioid users between January 2015 and August 2021. The time coefficient reflects the trend pre-pandemic and the interaction term coefficient represents the change in the trend during the pandemic.

RESULTS

The study included 1 313 519 RMD patients. New opioid users for RA, PsA and FM increased from 2.6, 1.0 and 3.4/10 000 persons in 2006 to 4.5, 1.8 and 8.7, respectively, in 2018 or 2019. This was followed by a fall to 2.4, 1.2 and 5.9, respectively, in 2021. Prevalent opioid users for all RMDs increased from 2006 but plateaued or dropped beyond 2018, with a 4.5-fold increase in FM between 2006 and 2021. In this period, MME/day increased for all RMDs, with the highest for FM (≥35). During COVID-19 lockdowns, RA, PsA and FM showed significant changes in the trend of prevalent opioid users. The trend for FM increased pre-pandemic and started decreasing during the pandemic.

CONCLUSION

The plateauing or decreasing trend of opioid users for RMDs after 2018 may reflect the efforts to tackle rising opioid prescribing in the UK. The pandemic led to fewer people on opioids for most RMDs, providing reassurance that there was no sudden increase in opioid prescribing during the pandemic.

Evaluation of interleukins (IL-1α, IL-1Ra, IL-12, IL-17A, IL-31, and IL-33) and chemokines (CXCL10 and CXCL16) in the serum of male patients with ankylosing spondylitis

BACKGROUND

A case-control study was performed to explore eight pro-inflammatory and anti-inflammatory cytokines, namely interleukin (IL)-1α, IL-1Ra (IL-1 receptor antagonist), IL-12, IL-17A, IL-31, IL-33, CXCL10 (C-X-C motif chemokine ligand 10), and CXCL16, with the aim to understand their role in ankylosing spondylitis (AS) pathogenesis and evaluate their utility as markers to differentiate between diseased and healthy individuals. Among these cytokines, IL-31 and CXCL16 have not been well studied in AS.

PATIENTS AND METHODS

The study included 94 male patients with AS and 91 age-matched control males. Interleukin and chemokine levels were measured using ELISA kits.

RESULTS

Serum levels of IL-17A, CXCL10, and CXCL16 were significantly elevated in patients compared to controls, while IL-31 levels were significantly decreased in patients. IL-17A, CXCL10, and CXCL16 were associated with an increased risk of AS, while IL-31 was associated with a decreased risk of disease (odds ratio = 1.22, 1.78, 1.14, and 0.89, respectively). As indicated by the area under the curve (AUC), IL-17A, IL-31, CXCL10, and CXCL16 were potential markers to differentiate between AS patients and controls (AUC = 0.877, 0.735, 0.8, and 0.7, respectively). IL-1α, IL-1Ra, IL-12, and IL-33 levels showed no significant variations between patients and controls.

CONCLUSIONS

Among the eight cytokines examined, IL-17A, CXCL10, and CXCL16 were up-regulated in the serum of AS patients, while IL-31 was down-regulated. The levels of IL-1α, IL-1Ra, IL-12, and IL-33 showed no significant differences between patients and controls. Serum levels of all cytokines were not affected by disease duration, HLA-B27 positivity, or disease activity.

Implications of Frailty on Postoperative Health Care Resource Utilization in Ankylosing Spondylitis Patients Undergoing Spine Surgery for Spinal Fractures

OBJECTIVE

The rise of spinal surgery for ankylosing spondylitis (AS) necessitates balancing health care costs with quality patient care. Frailty has been independently associated with adverse outcomes and increased costs. This study investigates whether frailty is an independent predictor of poor outcomes after elective surgery for AS.

METHODS

Using the National Inpatient Sample (NIS) database, a retrospective study was conducted on adult patients with AS who underwent posterior spinal fusion for fracture between 2016 and 2019. Each patient was assigned a modified frailty index (mFI) score and categorized as prefrail (mFI = 0 or 1), moderately frail (mFI = 2), and highly frail (mFI≥3). Multivariate logistic regression analyses were used to identify independent predictors of extended length of stay, non-routine discharge (NRD), and exorbitant admission costs.

RESULTS

Of the 1910 patients, 35.3% were prefrail, 31.2% moderately frail, and 33.5% highly frail. Age was significantly different across groups (P < 0.001), and frailty was associated with increased comorbidities (P < 0.001). Mean length of stay (P = 0.007), NRD rate (P < 0.001), and mean cost of admission (P = 0.002) all significantly increased with increasing frailty. However, frailty was not an independent predictor of extended hospital stay, NRD, or higher costs on multivariate analysis. Instead, predictors included multiple adverse events, number of comorbidities, and race.

CONCLUSIONS

While frailty in patients with AS is associated with older age, greater comorbidities, and increased adverse events, it was not an independent predictor of extended hospital stay, NRD, or higher hospital costs. Further research is required to understand the full impact of frailty on surgical outcomes and develop effective interventions.

Diagnosis and Treatment of Ankylosing Spondylitis

Ankylosing spondylitis (AS) is a chronic inflammatory condition primarily affecting the axial bone and sacroiliac joints. Its etiology is complicated and involves genetic variables, demographic factors (age of onset, gender, ethnicity, family history), and environmental variables. It typically manifests in males in their third decade. Galen is credited with first recognizing it, according to historical traditions, but it was not until the 19th century that specific diagnostic criteria were developed. The human leukocyte antigen B27 (HLA-B27) variation, around 20% of the genetic risk, is currently the most significant gene associated with AS susceptibility. Over 100 genes have been connected to AS susceptibility. Clinical signs of AS include stiffness and inflammation in the back, eye inflammation, aortitis (inflammation of the aorta), and spinal ankylosis that impacts posture and fatigue. The dagger sign and sacroiliitis on radiographs, in particular, are crucial for diagnosis. Early inflammatory alterations can be found using modern diagnostic tools such as MRI, and the HLA-B27 gene can help confirm the diagnosis. Overall, 80-95% of people with AS have the HLA-B27 marker. Furthermore, although non-specific, elevated inflammatory markers, such as C-reactive protein and erythrocyte sedimentation rate, offer supporting evidence. Over time, treatment paradigms have seen significant change. First-line treatments such as non-steroidal anti-inflammatory drugs are no longer the only options, even though disease-modifying anti-rheumatic drugs and biologics, especially tumor necrosis factor blockers, have been developed. Physical therapy, which emphasizes consistent exercise, stretches, and posture maintenance, is extremely helpful in managing AS. Surgical interventions can be required in extreme situations. The significance of the interleukin 23/17 axis in the disease cascade has been demonstrated by recent research. Furthermore, a deeper comprehension of the genetic landscape, mainly the functions of non-HLA-B27 loci, may open the door for more specialized therapies. Early diagnosis and interdisciplinary therapies can improve patient outcomes and quality of life as our understanding of AS grows.

Validation of diagnosis algorithms for ankylosing spondylitis in claim-based database

BACKGROUND

Claims-based algorithms using International Classification of Diseases (ICD) codes have become a common approach for researchers to define ankylosing spondylitis (AS) in studies. To address potential misclassification bias caused by the claim-based algorithms, we conducted the current study to validate whether these algorithms of medical claims could accurately represent AS diagnoses.

METHODS

Patients diagnosed with AS based on ICD codes were retrieved from the electronic medical records database at a Taiwanese medical center (Chung Shan University Hospital, Taiwan). After random sampling and stratification based on age and sex, the medical information of participants was appraised based on the 2009 ASAS guideline to evaluate the actual status of ICD codes claim-based AS patients. Positive predict values (PPV) of different algorithms of ICD codes were also calculated.

RESULTS

Within the 4160 patients with claim-based AS diagnosis, 387 eligible patients were finally included in the study design after random sampling. The PPV of the diagnostic algorithm of having at least 4 outpatient or 1 inpatient ICD record was 72.77 (95% CI, 66.79-78.75), whereas the PPV increased to 85.64 when the diagnoses were restricted to be made by rheumatologists (95% CI, 80.53-90.74).

CONCLUSIONS

While performing database studies, researchers should be aware of the low PPV of specific algorithms when defining AS. Algorithms with higher PPV were recommended to be adopted to avoid misclassification biases.

Prevalence of axial spondyloarthritis in Colombia: data from the National Health Registry 2017-2021

INTRODUCTION

Registries allow ascertaining the epidemiology of chronic diseases such as axial spondyloarthritis (axSpA). The Colombian Ministry of Health has implemented a National Health Registry (SISPRO) that collects data from each medical contact in the system, which provides close to universal coverage (around 98%).

OBJECTIVE

To establish the 5-year prevalence of axSpA in Colombia, and to describe its demographics, using data from January 1st, 2017, to December 31st, 2021.

METHODS

We performed an observational, cross-sectional study using the International Statistical Classification of Diseases and Related Health Problems as search terms related to ax-SpA, based on SISPRO data. We estimated the prevalence using three approaches: (1) ankylosing spondylitis (AS) diagnoses; (2) diagnoses compatible with axSpA; and (3) diagnoses compatible with axSpA, including sacroiliitis. We calculated prevalence per 100,000 inhabitants.

RESULTS

Based on our three approaches, patients with a primary diagnosis compatible with ax-SpA ranged between 12,684 and 117,648, with an estimated 5-year adjusted prevalence between 26.3 and 244 cases per 100,000 inhabitants (0.03-0.2%). The male-to-female ratio ranged between 1.2:1 and 0.4:1, which was markedly skewed towards a higher prevalence in women when we included the code for sacroiliitis. We found the highest frequency of cases in the 50-54 years group. A differential prevalence was observed between different regions in our country, particularly in regions known to have European ancestors.

CONCLUSION

This is the first study that describes demographic characteristics of ax-SpA in Colombia and offers valuable information for stakeholders. Key Points • Using the official country-level health database, the prevalence of axSpA in Colombia ranges between 26.3 and 244 cases per 100,000 inhabitants (0.03% - 0.2%) • The prevalence of axSpA peaked among the 50-54 years patient group, suggesting an increased survival • Nations with a substantial admixture, such as Colombia, may present a differential prevalence of axSpA among regions within the country • Including the ICD-10 code for sacroiliitis (M46.1) in epidemiological studies probably overestimates the frequency of axSpA.

Serum interα-trypsin inhibitor heavy chain H4 may be an anti-inflammatory marker reflecting disease risk, activity and treatment outcome of ankylosing spondylitis

Interα-trypsin inhibitor heavy chain H4 (ITIH4) modulates inflammation and immunity, which take part in the pathogenesis of ankylosing spondylitis (AS). The current research intended to discover the clinical value of serum ITIH4 quantification for AS management. Serum ITIH4 among 80 AS patients before current treatment initiation (baseline) at weeks (W) 4, 8 and 12 after treatment was detected by ELISA. Serum ITIH4 from 20 disease controls (DCs) and 20 healthy controls (HCs) was detected. ITIH4 expression was lower in AS patients than in DCs (p = 0.002) and HCs (p < 0.001). Among AS patients, ITIH4 was negatively associated with C-reactive protein (CRP) (r = -0.311, p = 0.005), bath AS disease activity index (BASDAI) (r = -0.223, p = 0.047), total pack pain (r = -0.273, p = 0.014) and AS disease activity score (ASDAS) (CRP) (r = -0.265, p = 0.018). Meanwhile, ITIH4 was negatively related to tumor necrosis factor (TNF)-α (r = -0.364, p = 0.001), interleukin (IL)-1β (r = -0.251, p = 0.025), IL-6 (r = -0.292, p = 0.009) and IL-17A (r = -0.254, p = 0.023). After treatment, the assessment of the spondylitis arthritis international society 40 response rate was 28.7% at W4, 46.3% at W8 and 55.0% at W12; ITIH4 showed an increasing trend from baseline to W12 (p < 0.001). Furthermore, ITIH4 at W8 (p = 0.020) and W12 (p = 0.035), but not at baseline or W4 (both p > 0.05), was enhanced in response patients vs. nonresponse patients. Additionally, ITIH4 at W12 was increased in AS patients receiving TNF inhibitors vs. those receiving nonsteroidal anti-inflammatory drugs (NSAIDs) (p = 0.024). Serum ITIH4 increases after treatment, and its augmentation is correlated with lower disease activity, decreased inflammation and enhanced treatment response in AS patients.

Differences of RUNX2 gene promoter methylation and transcription level in ankylosing spondylitis

BACKGROUND AND OBJECTIVE

Ankylosing spondylitis is a refractory immune disease that seriously affects the life and work of patients. Epigenetic modifications, especially DNA methylation, have become a research hotspot in complex diseases. We aim to explore the changes in runt-related transcription factor 2 (RUNX2) gene promoter methylation and transcription level in AS.

METHOD

We detected the RUNX2 gene promoter methylation in 83 AS patients and 83 healthy controls (HCs), then inspected the mRNA difference of RUNX2 between 30 AS patients and 30 HCs by the quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR).

RESULTS

The RUNX2 gene promoter was hypomethylated in AS patients compared to HCs (p < .001). The research involved 4 CpG regions and 74 CpG sites of RUNX2, of which CpG-2, CpG-4 regions, and 18 CpG sites have been differentially methylated. The CpG-4 island methylation was negatively correlated with C-reactive protein (p < .05) in AS patients. In the qRT-PCR validation phase, the mRNA level of RUNX2 in AS patients was significantly higher than HCs (p < .05), and in AS patients who were treated with biologics, the methylation level of CpG-2 island showed a negative correlation to mRNA (p < .05). ROC results indicated that RUNX2 methylation and its transcription level have good potential to distinguish AS patients from HCs.

CONCLUSION

The RUNX2 gene promoter was hypomethylated in AS patients. Meanwhile, the qRT-PCR verified the up-regulated expression on the transcription level, suggesting the abnormal methylation of RUNX2 contributes to the pathogenesis of AS.

First detection of cutavirus DNA in stools of patients with rheumatic diseases in Guangzhou, China

Cutavirus (CuV) is a novel protoparvovirus possibly associated with diarrhea and cutaneous T-cell lymphomas. Patients with rheumatic disease are immunosuppressed and may be more vulnerable to pathogenic viruses. A descriptive study was conducted among hospitalized patients with rheumatic diseases and individuals undergoing medical health check-ups between June 2019 and June 2022 in Guangzhou, China. Stool samples of subjects were tested for CuV DNA. Demographic and fecal examination data of patients were obtained from electronic medical records. A total of 505 patients with rheumatic diseases and 244 individuals who underwent medical health check-ups were included in the study. Of the patients with rheumatic disease, 5.74% [95% confidence interval (CI): 4.03%-8.12%] were positive for CuV DNA, while no individual in the medical health check-up group was positive, indicating a close correlation between CuV and rheumatic disease. Men and patients with rheumatoid arthritis or ankylosing spondylitis, according to the disease classification, were more susceptible to being infected with CuV (P ​< ​0.01). After adjustments, being male remained the only significant factor, with an adjusted odd ratio (OR) of 4.4 (95% CI: 1.7-11.4, P ​= ​0.002). Phylogenetic analysis of the CuV VP2 sequences showed three diverse clades, one of which was segregated to be a single branching independent of previously known sequences, which is possible a new genotype.

Epidemiology of the idiopathic inflammatory myopathies

The idiopathic inflammatory myopathies (IIMs) are a heterogeneous group of systemic autoimmune diseases that affect the skeletal muscles and can also involve the skin, joints, lungs and heart. The epidemiology of IIM is obscured by changing classification criteria and the inherent shortcomings of case identification using healthcare record diagnostic coding. The incidence of IIM is estimated to range from 0.2 to 2 per 100,000 person-years, with prevalence from 2 to 25 per 100,000 people. Although the effects of age and gender on incidence are known, there is only sparse understanding of ethnic differences, particularly in indigenous populations. The incidence of IIM has reportedly increased in the twenty-first century, but whether this is a genuine increase is not yet known. Understanding of the genetic risk factors for different IIM subtypes has advanced considerably. Infections, medications, malignancy and geography are also commonly identified risk factors. Potentially, the COVID-19 pandemic has altered IIM incidence, although evidence of this occurrence is limited to case reports and small case series. Consideration of the current understanding of the epidemiology of IIM can highlight important areas of interest for future research into these rare diseases.

Conquering rheumatic diseases: are parasitic worms the answer?

Despite the introduction of novel treatment strategies, management of rheumatic disorders remains associated with substantial unmet clinical need. Of interest therefore, it has recently become apparent that there is a global inverse relationship between the incidence of such conditions and parasitic helminth infection, with striking examples involving rheumatoid arthritis (RA)/systemic lupus erythematosus (SLE) patients and filarial nematode worm infection in studies in India. Such findings reflect that helminths are master manipulators of the immune system, particularly in being able to modulate proinflammatory responses. The aim of this article is thus to consider findings to date on this exciting and intriguing research area to form an opinion on whether parasitic worms may be exploited to generate novel therapies for rheumatic diseases.

Diagnostic delay in axial spondylarthritis: A lost battle?

Diagnostic delay in axial spondylarthritis (axSpA) remains an unacceptable worldwide problem; with evidence suggesting significant detrimental impact both clinically on the individual, and economically on society. There is therefore, a need for global action across various healthcare professions that come into contact with patients living, and suffering, with undiagnosed axSpA. Recent estimates of the median diagnostic delay suggest that globally, individuals with axSpA wait between 2 and 6 years for a diagnosis - revealing a clear benchmark for improvement. This timespan presents a window of opportunity for earlier diagnosis and intervention, which will likely improve patient outcomes. This review describes the current diagnostic delay as estimated across countries and over time, before presenting evidence from published strategies that may be implemented to improve this delay across primary and secondary care, including for specialties treating extra-musculoskeletal manifestations of axSpA (ophthalmology, gastroenterology, dermatology). Ongoing campaigns tackling delayed diagnosis in axSpA are also highlighted.

Quality of Life and Related Factors in Patients With Ankylosing Spondylitis: A Cross-Sectional Study Using 36-Item Short Form Survey (SF-36)

BACKGROUND

 Ankylosing spondylitis is a chronic condition that affects the vertebral and sacroiliac joints, causing progressive back pain and stiffness. Patients with this condition experience a lower quality of life compared to the general population, with physical health being more impacted than mental health. In Vietnam, little attention has been given to the quality of life of patients with ankylosing spondylitis, and there are conflicting studies on the factors that affect their quality of life. Therefore, it is essential to assess the quality of life of these patients to provide appropriate recommendations for improving their overall well-being.

METHODOLOGY

The descriptive cross-sectional study was conducted on patients with ankylosing spondylitis who visited University Medical Center Ho Chi Minh City from March 2022 to May 2022. Participants were interviewed face-to-face using the 36-item short form survey (SF-36) questionnaire and the visual analogue scale. In addition, some information related to ankylosing spondylitis was also collected through medical records.

RESULTS AND CONCLUSION

Seventy-five patients met the inclusion criteria with a median age of 33 (26 - 37); men accounted for 68%. The mean physical and mental health scores on the SF-36 scale were 37.73 ± 9.30 and 47.04 ± 7.11, respectively. Young age, lower pain score and duration of illness, and higher education were associated with a high physical health score with p<0.05. Similarly, the educational level and occupation were positively correlated, and pain scores were inversely correlated with mental health with p< 0.05.

Investigating the causal relationship between ankylosing spondylitis and osteoporosis in the European population: a bidirectional Mendelian randomization study

Background

Ankylosing Spondylitis (AS) is an inflammatory condition affecting the spine, which may lead to complications such as osteoporosis (OP). Many observational studies have demonstrated a close relationship with strong evidence between OP and AS. The combination of AS and OP is already an indisputable fact, but the exact mechanism of AS complicated with OP is unclear. To better prevent and treat OP in patients with AS, it is necessary to understand the specific mechanism of OP in these patients. In addition, there is a study showing that OP is a risk factor for AS, but the causal relationship between them is not yet clear. Therefore, we conducted a bidirectional Mendelian randomization (MR) analysis to determine whether there is a direct causal effect between AS and OP and to investigate the co-inherited genetic information between the two.

Methods

Bone mineral density (BMD) was used as a phenotype for OP. The AS dataset was taken from the IGAS consortium and included people of European ancestry (9,069 cases and 13,578 controls). BMD datasets were obtained from the GEFOS consortium, a large GWAS meta-analysis study, and the UK Biobank and were categorized based on site (total body (TB): 56,284 cases; lumbar spine (LS): 28,498 cases; femoral neck (FN): 32,735 cases; forearm (FA): 8,143 cases; and heel: 265,627 cases) and age (0-15: 11,807 cases; 15-30: 4,180 cases; 30-45: 10,062 cases; 45-60: 18,062 cases; and over 60: 22,504 cases).To obtain the casual estimates, the inverse variant weighted (IVW) method was mainly used due to its good statistical power and robustness. The presence of heterogeneity was evaluated using Cochran's Q test. Pleiotropy was assessed utilizing MR-Egger regression and MR-pleiotropy residual sum and outlier (MR-PRESSO).

Results

Generally, there were no significant causal associations between genetically predicted AS and decreased BMD levels. The results of MR-Egger regression, Weighted Median, and Weighted Mode methods were consistent with those of the IVW method. However, there was a sign of a connection between genetically elevated BMD levels and a decreased risk of AS (Heel-BMD: OR = 0.879, 95% CI: 0.795-0.971, P = 0.012; Total-BMD: OR = 0.948, 95% CI: 0.907-0.990, P = 0.017; LS-BMD: OR = 0.919, 95% CI: 0.861-0.980, P = 0.010). The results were confirmed to be reliable by sensitivity analysis.

Conclusion

This MR study found that the causal association between genetic liability to AS and the risk of OP or lower BMD in the European population was not evident, which highlights the second effect (e.g., mechanical reasons such as limited movement) of AS on OP. However, genetically predicted decreased BMD/OP is a risk factor for AS with a causal relationship, implying that patients with OP should be aware of the potential risk of developing AS. Moreover, OP and AS share similar pathogenesis and pathways.

Impacts of gait biomechanics of patients with thoracolumbar kyphosis secondary to Scheuermann's disease

Introduction: Thoracolumbar kyphosis (TLK) is a common feature in patients with spinal deformities. However, due to limited studies, the impacts of TLK on gait have not been reported. The objective of the study was to quantify and evaluate the impacts of gait biomechanics of patients with TLK secondary to Scheuermann's disease. Methods: Twenty cases of Scheuermann's disease patients with TLK and twenty cases of asymptomatic participants were recruited into this study. And the gait motion analysis was conducted. Results: The stride length was shorter in the TLK group compared to control group (1.24 ± 0.11 m vs. 1.36 ± 0.21 m, p = 0.04). Compared to control group, the stride time and step time were more prolonged in the TLK group (1.18 ± 0.11s vs. 1.11 ± 0.08 s, p = 0.03; 0.59 ± 0.06 s vs. 0.56 ± 0.04 s, p = 0.04). The gait speed of the TLK group was significantly slower than it of control group (1.05 ± 0.12 m/s vs. 1.17 ± 0.14 m/s, p = 0.01); In the sagittal plane, the range of motion (ROM) of the hip in the TLK group was significantly smaller than that of the control group (37.71 ± 4.35° vs. 40.05 ± 3.71°, p = 0.00). In the transverse plane, the adduction/abduction ROMs of the knee and ankle, as well as the internal and external rotation of the knee, were smaller in TLK group than ROMs in the control group (4.66 ± 2.21° vs. 5.61 ± 1.82°, p = 0.00; 11.48 ± 3.97° vs. 13.16 ± 5.6°, p = 0.02; 9.00 ± 5.14° vs. 12.95 ± 5.78°, p = 0.00). Discussion: The main finding of this study was that measurements of gait patterns and joint movement of the TLK group were significantly lower than those of the control group. And these impacts have the potential to exacerbate degenerative progress of joints in the lower extremities. These abnormal features of gait can also serve as a guideline for physicians to focus on TLK in these patients.

Pre-treatment calprotectin (MRP8/14) provides no added value to testing CRP alone in terms of predicting response to TNF inhibitors in rheumatoid arthritis in a post hoc analysis

OBJECTIVES

The inflammatory protein calprotectin (MRP8/14) has been identified as a promising biomarker of treatment response in rheumatoid arthritis (RA). Our aim was to test MRP8/14 as a biomarker of response to tumour necrosis factor (TNF)-inhibitors in the largest RA cohort to date and to compare with C-reactive protein (CRP).

METHODS

Serum MRP8/14 was measured in 470 patients with RA about to commence treatment with adalimumab (n=196) or etanercept (n=274). Additionally, MRP8/14 was measured in the 3-month sera of 179 adalimumab-treated patients. Response was determined using European League against Rheumatism (EULAR) response criteria calculated using the traditional 4-component (4C) DAS28-CRP and alternate validated versions using 3-component (3C) and 2-component (2C), clinical disease activity index (CDAI) improvement criteria and change in individual outcome measures. Logistic/linear regression models were fitted for response outcome.

RESULTS

In the 3C and 2C models, patients with RA were 1.92 (CI: 1.04 to 3.54) and 2.03 (CI: 1.09 to 3.78) times more likely to be classified as EULAR responders if they had high (75th quartile) pre-treatment levels of MRP8/14 compared with low (25th quartile). No significant associations were observed for the 4C model. When only using CRP as a predictor, in the 3C and 2C analyses, patients above the 75th quartile were 3.79 (CI: 1.81 to 7.93) and 3.58 (CI: 1.74 to 7.35) times more likely to be EULAR responders and addition of MRP8/14 did not significantly improve model fit (p values=0.62 and 0.80, respectively). No significant associations were observed in the 4C analysis. Exclusion of CRP from the outcome measure (CDAI) did not result in any significant associations with MRP8/14 (OR 1.00 (CI: 0.99 to 1.01), suggesting that the associations were due to the correlation with CRP and that there is no additional utility of MRP8/14 beyond use of CRP in patients with RA starting TNFi therapy.

CONCLUSION

Beyond correlation with CRP, we found no evidence to suggest that MRP8/14 explains additional variability in response to TNFi in patients with RA over and above CRP alone.

Perioperative treatment with TNF inhibitors does not affect survival of total hip arthroplasty in inflammatory arthritis: a registry-based cohort study

OBJECTIVES

Aim of this study was to investigate the effect of perioperative exposure to TNF inhibitors (TNFi) on the long-term survival of total hip arthroplasty (THA) in inflammatory arthritis patients from a large regional register of arthroplasty procedures (RIPO).

METHODS

This study is a retrospective analysis of data from RIPO for THAs performed between 2008 and 2019. After extraction of the procedures of interest from the RIPO dataset, cross-matching with administrative databases were used to identify patients with rheumatoid arthritis (RA), psoriatic arthritis (PsA), ankylosing spondylitis (AS), primary osteoarthritis (OA), and treatments of interest. Three different cohorts of patients were identified: perioperative TNFi-treated patients (6 months before or after the surgery), perioperative non-bDMARD/tsDMARD (biologic or targeted-synthetic disease modifying antirheumatic drugs), and OA.

RESULTS

At an average follow-up of 5 years, survival rates (using any revision surgery as an endpoint) were not significantly different when perioperative TNFi users and non-bDMARD/tsDMARD patients were compared (p = 0.713), and between TNFi-treated and OA controls (p = 0.123). At the latest available follow-up, 2.5% patients in the TNFi cohort, 3% in the non-bDMARD/tsDMARD cohort, and 0.8% in the OA cohort underwent revision surgery. No significant differences were found comparing the risk of postoperative infection or aseptic loosening among groups.

CONCLUSION

Risk of revision surgery is not increased in patients with inflammatory arthritis perioperatively exposed to TNFi. Our results support the long-term safety of this class of molecules on survival of prosthetic implants.

Association of vascular endothelial growth factor serum levels with ankylosing spondylitis in Egyptian patients

Background

Ankylosing spondylitis (AS) is one of inflammatory rheumatic diseases which result in wide range of manifestations on the musculoskeletal system and axial joint specifically. Endothelial cell migration and proliferation, as well as subsequent neoangiogenesis and remodelling in autoimmune disorders, are pathogenic mechanisms that are fundamental to inflammation activation and angiogenesis. The development of advanced lesions is thought to involve vascular proliferation as well as vascular endothelial growth factor (VEGF), which serves a regulatory role. It was found that AS patients had increased serum levels of VEGF, which were linked to the disease activity.

Aim of the work

The purpose of this study is to measure serum VEGF levels in Egyptian AS patients and assess their relation to disease-related variables, including radiographic findings.

Results

VEGF serum levels showed a highly significant positive correlation with Bath Ankylosing Spondylitis Functional Index (BASFI) and modified Stroke Ankylosing Spondylitis Spinal Score (MSASS) (p < 0.001); also, there was a significant correlation between the VEGF values and the Ankylosing Spondylitis Disease Activity Index (ASDAS) and the New York x-ray sacroiliac score.

Conclusions

These findings and data illustrate the strong relationship between ASDAS and VEGF and the radiographic score in AS patients. ASDAS combined with VEGF not only is considered a tool for determining the level of disease activity only but also is considered as an indicator for the assessment of the syndesmophytes formation, which performs a crucial role in the prognosis and outcome in AS patients.

Risk of Multiple Sclerosis Among Users of Antitumor Necrosis Factor α in 4 Canadian Provinces: A Population-Based Study

BACKGROUND AND OBJECTIVES

Antitumor necrosis factor α (TNFα) agents are a class of biologic drugs used for the treatment of several immune-mediated conditions. An increased risk of multiple sclerosis (MS) with their use has been suggested, but studies have been limited. Relevant population-based epidemiologic data linking anti-TNFα to MS are scarce. The objective was to compare the risk of MS in anti-TNFα users with nonusers among patients with rheumatic disease (RD) or inflammatory bowel disease (IBD).

METHODS

A nested case-control study was conducted. Population-based health care-linked databases from 4 Canadian provinces were used. All patients with RD or IBD residing within a participating province between January 2000 and March 2018 were identified by validated case definitions. Any anti-TNFα dispensation in the 2 years before the index date (MS onset) was identified. Incident onset MS cases were ascertained using a validated algorithm. Up to 5 controls were matched to each MS case based on birth year ±3 years, disease duration, and health authority (based on region of residence). Conditional logistic regressions were used to calculate the incidence rate ratio (IRR) after adjusting for potential confounders. A meta-analysis was conducted to provide pooled estimates across provinces using random-effects models.

RESULTS

Among 296,918 patients with RD patients, 462 MS cases (80.1% female, mean [SD] age, 47.4 [14.6] years) were matched with 2,296 controls (59.5% female, mean [SD] age, 47.4 [14.5] years). Exposure to anti-TNFα occurred in 18 MS cases and 42 controls. After adjusting for matching variables, sex, and the Charlson Comorbidity Index, the pooled IRR was 2.05 (95% CI, 1.13-3.72). Among 84,458 patients with IBD, 190 MS cases (69.5% female, mean [SD] age, 44.3 [12.3] years) were matched with 943 controls (54.1% female, mean [SD] age, 44.2 [12.2] years). Exposure to anti-TNFα occurred in 23 MS cases and 98 controls. The pooled adjusted IRR was 1.35 (95% CI, 0.70-2.59).

DISCUSSION

The use of anti-TNFα was associated with an increased risk of MS compared with nonusers, especially among patients with RD. These findings could help clinicians and patients with RD to make more informed treatment decisions. Further studies are needed to validate these results for patients with IBD.

No Evidence to Support a Causal Relationship between Circulating Adiponectin Levels and Ankylosing Spondylitis: A Bidirectional Two-Sample Mendelian Randomization Study

Based on previous observational studies, the causal association between circulating adiponectin (CA) levels and ankylosing spondylitis (AS) risk remains unclear. Therefore, this study aims to investigate whether CA levels are related to the risk of AS. We carried out a bidirectional two-sample Mendelian randomization (MR) analysis to examine the causal correlation between CA levels and AS via published genome-wide association study (GWAS) datasets. Single-nucleotide polymorphisms (SNPs) related to CA levels were derived from a large GWAS that included 39,883 individuals of European descent. SNPs related to AS were obtained from the FinnGen consortium (2252 cases and 227,338 controls). The random-effects inverse variance weighted (IVW) method was the primary method utilized in our research. We also used four complementary approaches to improve the dependability of this study (MR-Egger regression, Weighted median, Weighted mode, and Simple mode). Random-effects IVW (odds ratio [OR], 1.00; 95% confidence interval [CI], 0.79-1.27, p = 0.984) and four complementary methods all indicated that genetically predicted CA levels were not causally related to the risk of AS. In reverse MR analysis, there is little evidence to support the genetic causality between the risk of AS and CA levels.

Development and Validation of a Machine Learning-Based Nomogram for Prediction of Ankylosing Spondylitis

Introduction

Ankylosing spondylitis (AS) is a chronic progressive inflammatory disease of the spine and its affiliated tissues. AS mainly affects the axial bone, sacroiliac joint, hip joint, spinal facet, and adjacent ligaments. We used machine learning (ML) methods to construct diagnostic models based on blood routine examination, liver function test, and kidney function test of patients with AS. This method will help clinicians enhance diagnostic efficiency and allow patients to receive systematic treatment as soon as possible.

Methods

We consecutively screened 348 patients with AS through complete blood routine examination, liver function test, and kidney function test at the First Affiliated Hospital of Guangxi Medical University according to the modified New York criteria (diagnostic criteria for AS). By using random sampling, the patients were randomly divided into training and validation cohorts. The training cohort included 258 patients with AS and 247 patients without AS, and the validation cohort included 90 patients with AS and 113 patients without AS. We used three ML methods (LASSO, random forest, and support vector machine recursive feature elimination) to screen feature variables and then took the intersection to obtain the prediction model. In addition, we used the prediction model on the validation cohort.

Results

Seven factors—erythrocyte sedimentation rate (ESR), red blood cell count (RBC), mean platelet volume (MPV), albumin (ALB), aspartate aminotransferase (AST), and creatinine (Cr)—were selected to construct a nomogram diagnostic model through ML. In the training cohort, the C value and area under the curve (AUC) value of this nomogram was 0.878 and 0.8779462, respectively. The C value and AUC value of the nomogram in the validation cohort was 0.823 and 0.8232055, respectively. Calibration curves in the training and validation cohorts showed satisfactory agreement between nomogram predictions and actual probabilities. The decision curve analysis showed that the nonadherence nomogram was clinically useful when intervention was decided at the nonadherence possibility threshold of 1%.

Conclusion

Our ML model can satisfactorily predict patients with AS. This nomogram can help orthopedic surgeons devise more personalized and rational clinical strategies.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40744-022-00481-6.

AS is a chronic progressive inflammatory disease of the spine and its affiliated tissues. AS starts gradually, and its early symptoms are mild. Some hospitals lack HLA-B27 and related imaging instruments to assist in the diagnosis of AS. There are relatively few studies on liver function and kidney function of patients with AS. We used ML methods to construct diagnostic models. Our model can satisfactorily predict patients with AS. This diagnostic model can help orthopedic surgeons devise more personalized and rational clinical strategies.

DNA Methylation and mRNA Expression of B7-H3 Gene in Ankylosing Spondylitis: A Case-Control Study

BACKGROUND

Ankylosing spondylitis (AS) is a common inflammatory arthritis, with a high prevalence in patients in their mid-20s. Its pathogenesis is not well understood; however, genetic factors likely play a critical role. Epigenetic DNA changes may be involved in the pathogenesis of AS. In this study, we explored the methylation and transcription levels of the B7-H3 gene and its association with AS in an eastern Chinese Han population.

METHODS

Peripheral blood of AS patients and healthy controls was used to extract genomic DNA and B7-H3 methylation levels were analyzed using sodium bisulfite followed by multiplex polymerase chain reaction. SPSS software was used to determine the statistical significance of the results.

RESULTS

Hypomethylation of the promoter of the B7-H3 gene was observed in AS patients, whereas the B7-H3 gene expression was significantly enhanced in AS patients.

CONCLUSION

Epigenetic modifications of B7-H3 were associated with susceptibility to AS. Hypomethylation of the B7-H3 promoter, which leads to B7-H3 overexpression, may be involved in the pathogenesis of AS.

A Survey of Diagnostic Delay in Axial Spondyloarthritis Across Two National Health Service (NHS) Rheumatology Services

Introduction

Diagnostic delay is an ongoing challenge in axial spondyloarthritis (axial SpA). A recent, comprehensive literature review has found a mean average of 8.7 years of delay between symptom onset and formal diagnosis in the United Kingdom (UK). The primary aim of this study was to identify delays to diagnosis experienced by patients with axial SpA under the ongoing care of two urban National Health Service (NHS) rheumatology services. The secondary aims were (a) to count healthcare professional (HCP) interactions after symptom onset but prior to the diagnosis, (b) to compare our data to published delay to diagnosis research and (c) to explore contributing factors locally and the variation between the two UK rheumatology services.

Methods

A 14-question survey was created to identify the delay to diagnosis and contributing factors across two urban NHS axial SpA services, from the onset of symptoms to diagnosis and commencement of treatment. Participants were recruited from clinic visits between August and November 2021 and completed the survey either on paper or via online survey software, both with HCP support.

Results

Those completing the survey formed a cohort of 106 participants with an established diagnosis of axial SpA who attended the axial SpA services at either Royal Free NHS Foundation Trust or Salford Care Organisation, Northern Care Alliance NHS Foundation Trust. The mean time from the onset of symptoms to the diagnosis of axial SpA was similar across centres despite the differences in demographics, with Royal Free at 5.72 years and Salford Royal at 5.96 years. When reviewing via median diagnostic delay, there was a notable difference with Royal Free at 6.09 years and Salford Royal at 4.27 years.

Across the two sites, between the onset of symptoms and the diagnosis of axial SpA, 90% of the participants saw a general practitioner (GP), of which 63% of the patients saw a GP 1-5 times, 23% saw 5-10 times and 14% saw more than 10 times. Many participants also saw other HCPs, including physiotherapists, other manual therapists and hospital specialists prior to diagnosis. In addition, 32% saw one other HCP, 18% two other HCPs, 9% three, 7% four and 2.7% five other HCPs prior to diagnosis. Close to 80% of the patients stated that they had received adequate axial SpA education at diagnosis, and 76% of the patients were aware of who to contact in the event of a flare.

Conclusions

These data highlight that the mean average time to diagnosis for both trusts was between five and six years, somewhat lower than the 8.7-year national UK average. However, despite being specialist centres, these data are a long way from the National Axial Spondyloarthritis Society (NASS) “Gold Standard” of one year time to diagnosis. The contributors to this include lack of HCP and community awareness about axial SpA, its recognition and appropriate onwards referral. There is a need for concerted ways of working for the development of patient pathways and public and HCP education to reduce this delay to allow the ambitious NASS Gold Standard of one year time to diagnosis to be achieved.