Differences between women and men with recent-onset axial spondyloarthritis: results from a prospective multicenter French cohort

The role of social determinants of health on disease outcomes in axial spondyloarthritis: A narrative review

This review provides a narrative exploration of the literature on various social determinants of health that influence outcomes in axial Spondyloarthritis (axSpA). By using the PROGRESS-Plus framework (place of residence, race, occupation, gender/sex, religion, education, socioeconomic status, social capital, age), this review discusses how these factors have been studied and their impact on disease outcomes in axSpA. The findings suggest that various patient-level factors (e.g. female sex, blue-collar jobs, low educational level) and country-level factors (e.g. low-income countries) associate with worse health outcomes in axSpA. These insights highlight the importance of adopting a multifaceted and holistic approach, that also considers social determinants of health, when managing patients with axSpA. This work also identifies unmet needs in this area including the importance of thinking beyond just biological factors, when considering drivers of suboptimal outcomes in axSpA.

Associations of sociodemographic, clinical factors and HLA-B alleles with enthesitis and peripheral arthritis in patients with ankylosing spondylitis

OBJECTIVES

Factors associated with peripheral arthritis and enthesitis, especially Achilles tendonitis and plantar fasciitis, were examined in a longitudinal cohort of 1075 patients with ankylosing spondylitis (AS) (also known as radiographic axial spondyloarthritis).

METHODS

Patients were derived from the Prospective Study of Outcomes in Ankylosing Spondylitis cohort. Disease activity and functional indices, as well as physical examination and medications used, were measured at every study visit. Univariable and multivariable analyses of the association of peripheral arthritis and enthesitis with clinical, sociodemographic factors were performed. Human leucocyte antigen (HLA)-B alleles were analysed by single-stranded conformational polymorphism analysis.

RESULTS

Those with peripheral arthritis on examination were more likely to have psoriasis (p=0.001, OR=1.68; CI, 1.11, 2.54), greater functional impairment (p<0.001 OR=1.72; CI, 1.31, 2.27), higher erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) levels (p<0.001), greater tumour necrosis factor (TNF) inhibitor (p<0.001, OR=1.50; CI, 1.14, 1.97) and use methotrexate/sulfasalazine (p<0.001, OR=2.25, CI [1.57, 3.23]). Patients with enthesitis were less likely to be male (p<0.001, OR=0.57; CI, 0.43, 0.75) and have peripheral arthritis (p<0.001, OR=2.35; CI, 1.47, 3.75), greater functional impairment (p<0.001, OR=1.91; CI, 1.43, 2.55) and higher ESR/CRP levels (p<0.001). Patients with plantar fasciitis and/or Achilles' tendonitis on examination were less likely to male (p<0.001 OR=0.57; CI, 0.43, 0.75), to have significant functional impairment (p<0.001), to be using TNF inhibitors (p<0.001, OR=1.48; CI 1.13, 1.93) and to be using either sulfasalazine or methotrexate (p<0.001, OR=1.86, CI, 1.30, 2.67). HLA-B*15 (p=0.03, OR=1.84; CI, 1.05, 3.21) and HLA-B*37 (p=0.04, OR=3.00; CI, 1.03, 8.74) were marginally increased in frequency in those with peripheral arthritis on examination compared with those without.

CONCLUSION

There was a higher prevalence of peripheral musculoskeletal manifestations in women with AS, with significant impact on physical function and greater use of methotrexate or sulfasalazine and TNF inhibitors and enrichment for certain non-HLA-B27 HLA-B alleles.

Distribution of human leukocyte antigen B27 (HLA-B27) in Slovak patients

BACKGROUND AND OBJECTIVES

HLA-B27 is a genetic marker associated with spondyloarthropathies, particularly ankylosing spondylitis and axial spondyloarthritis. While its prevalence varies across populations, no data exist for Slovak patients. This study aimed to determine HLA-B27 prevalence in Slovak patients with suspected spondyloarthropathies and assess differences by sex and age.

METHODS

A retrospective cohort of 1,614 patients (888 females and 726 males) was analyzed for HLA-B27 status (positive/negative) using reverse hybridisation (HLA-B27 StripAssay). Statistical analyses included Pearson's Chi-square test and non-parametric Mann-Whitney U and Kruskal-Wallis tests for sex- and age-related differences.

RESULTS

HLA-B27 positivity was 20.57%, with a higher proportion in males (23.28%) than females (18.36%, p = 0.0177). The less than 20 age group had the highest absolute number of positive cases (126 cases; 17.80%), while the 21-40 group had the highest relative positivity (119 cases; 29.38%). The lowest positivity was in the more than 61 age group (17 cases; 13.08%), though age distribution differences were not statistically significant (p = 0.7765). Positivity varies across diagnoses, peaking in musculoskeletal (M) and eye disorders (H), where it exceeds 29%.

CONCLUSION

HLA-B27 positivity is strongly associated with rheumatologic and ophthalmologic conditions and exhibits age- and sex-related variability. These findings emphasize the diagnostic significance of HLA-B27 testing in Slovak patients, especially for early detection and management of spondyloarthropathies. Further research on HLA-B27 variability and its clinical implications is needed to optimize diagnostic strategies and patient care.

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.

Low Socioeconomic Status and Female Sex are Associated With Worse Functional Status in Axial Spondyloarthritis

OBJECTIVE

We determined whether socioeconomic status (SES) and sex are associated with functional status (FS) in axial spondyloarthritis (axSpA).

METHODS

We conducted a cohort study of patients with axSpA in the Rheumatology Informatics System for Effectiveness registry. We performed cross-sectional and longitudinal analyses of FS through the Multidimensional Health Assessment Questionnaire (MDHAQ) using generalized estimating equation models. Area Deprivation Index (ADI) was used as an SES proxy. The cross-sectional analysis tested for a linear trend across ADI quintiles for MDHAQ. The longitudinal analysis' outcome was functional decline. We reported predictive margins and assessed for interaction with sex. In the longitudinal analysis, we reported odds of functional decline.

RESULTS

In the cross-sectional analysis (N = 5,658), the mean ± SD age was 53.8 ± 15.2 years, 55.8% were female, and 71.4% were non-Hispanic White. The mean ± SD MDHAQ scores were 1.6 ± 2.0 in men versus 2.1 ± 2.2 in women. Predicted mean MDHAQ scores were 2.2 (95% confidence interval [CI] 1.8-2.7) for the lowest ADI quintile and 1.8 (95% CI 1.4-2.1) for the highest. Women had lower FSs compared to men across quintiles. In the longitudinal analysis (n = 2,341), the proportion with FS decline was 14.3% (95% CI 7.6-25.5%) for the lowest SES quintile compared to 9.6% (95% CI 5.2-17.1%) for the highest. Women had 1.7 (95% CI 1.3-2.2) times higher odds of functional decline compared to men. There was no interaction with sex.

CONCLUSION

In this large sample of patients with axSpA, those with lower SES had worse FS and functional decline. Women had worse FS than men, initially and over time.

Impact of clinical subtype and sex on first-line biologic therapy discontinuation in axial spondyloarthritis

OBJECTIVES

To estimate the main and interaction effects of axial spondyloarthritis (axSpA) subtype and sex on first biologic disease-modifying antirheumatic drug (bDMARD) discontinuation.

METHODS

This retrospective cohort study included nonradiographic axSpA (nr-axSpA) and radiographic axSpA (r-axSpA) patients initiating tumour necrosis factor or interleukin-17 inhibitors. Modified Poisson regressions were used to estimate risk ratios (RRs) for the association of subtype and sex with discontinuation, adjusting for baseline covariates. Interaction was assessed using the relative excess risk due to interaction (RERI) and ratio of RRs. In addition, bDMARD survival rates were analysed using Kaplan-Meier curves.

RESULTS

Among 469 patients, 64% discontinued their first bDMARD. Nr-axSpA (RR, 1.80; 95% CI, 1.26-2.59) and female sex (RR, 1.49; 95% CI, 1.081-2.045) were significantly associated with discontinuation. Positive interaction trends between subtype and sex were observed on additive (RERI 0.49, 95% CI, -0.78 to 1.75) and multiplicative (RR ratio, 1.05; 95% CI, 0.55-2.03) scales, though not statistically significant. Nr-axSpA females had twice the discontinuation risk of r-axSpA males (hazard ratio, 2.30; 95% CI, 1.68-3.15, P < .001). bDMARD survival over 20 years was significantly lower in nr-axSpA and female patients.

CONCLUSIONS

Nr-axSpA and female patients face a significantly higher risk of bDMARD discontinuation and shorter bDMARD survival. Although the combined effect of subtype and sex trended higher, it was not statistically significant. These findings underscore the need to address potential treatment challenges in female nr-axSpA patients.

Perceived effects of health status on sexual activity in patients with axial spondyloarthritis: a 5-year follow-up study

Axial spondyloarthritis (ax-SpA) causes pain, fatigue, stiffness, loss of physical function, and poor health status, which can influence sexual activity and enjoyment. To explore whether patients with ax-SpA perceive that their health status effects their sexual activity and to identify predictors of these perceived effects on sexual activity after a 5-year follow-up. Data about demographics, disease, medication, health-related quality of life (HRQOL), and sexual quality of life (SQOL) were collected at the baseline and 5-year follow-up. The perceived effect of health status on sexual activity was measured by question 15 in the 15D questionnaire. Data were analysed using the McNemar and independent paired t tests and logistic regression. In the 244 patients with ax-SpA (30% women, 70% men; mean age, 46 years), measures reflecting disease activity decreased and comorbidities increased, and more patients were treated with biological drugs at 5 years. Compared with patients whose health status had little/no effect on sexual activity (n = 200), those who perceived that their health status had a large effect on sexual activity (n = 44) were older, exercised less, fewer were employed, had more comorbidities, higher disease activity, and lower HRQOL and SQOL. The baseline predictors of a negative effect of health status on sexual activity were old age and low SQOL. Patients reporting that their health status had a large effect on sexual activity at 5 years were older, had more disease activity, and lower HRQOL and SQOL.

Females With Axial Spondyloarthritis Have Longer Diagnostic Delay and Higher Burden of the Disease. Results From the International Map of Axial Spondyloarthritis (IMAS)

BACKGROUND

To assess gender differences in a large sample of patients included in the International Map of Axial Spondyloarthritis (IMAS) study from around the globe.

METHOD

IMAS is a cross-sectional online survey (2017-2022) of 5557 unselected axSpA patients from 27 countries. The current analysis assessed differences between males and females for: sociodemographic, health behaviors, disease characteristics, patient-reported outcomes, mental comorbidities, and treatments. Univariable and multivariable logistic regression analysis was used to evaluate the relationship between gender and disease characteristics, patient-reported outcomes, comorbidities, and treatments.

RESULTS

Data from 5555 patients reporting gender were analyzed: 3492 from Europe, 769 from North America, 600 from Asia, 548 from Latin America, and 146 from Africa. Globally, 55.4% were females, with higher proportions in South Africa (82.2%) and lower in Asia (20.8%). Compared to males, a lower percentage of females smoked and consumed alcohol. The diagnostic delay was significantly longer (+2.4 years) in females, while the frequency of HLA-B27 positivity of axSpA was lower in females. The use of axSpA pharmacological treatment was more common in females with a higher proportion having ever taken nonsteroidal anti-inflammatory drugs (NSAIDs), conventional synthetic DMARDs (csDMARDs), and biologic DMARDs (bDMARDS).

CONCLUSIONS

Identifying the specific disease characteristics associated with gender in patients with axSpA may help to improve the diagnosis and management of the disease, and thereby reduce the disease burden for patients around the world.

Effect of gender and age on bDMARD efficacy for axial spondyloarthritis patients: a meta-analysis of randomized controlled trials

OBJECTIVE

To study the therapeutic variations of biologic and targeted synthetic DMARDs (b/tsDMARDs) between genders and across age stages in axial SpA (axSpA) patients through meta-analysis.

METHODS

Randomized controlled trials published by PubMed, Scopus and Embase before 10 August 2023, testing the efficacy of b/tsDMARDs in axSpA, were searched and systematically reviewed. The Assessment of Spondyloarthritis International Society ≥40% improvement (ASAS40) was used as the primary outcome of treatment response.

RESULTS

Only one study meet the inclusion criteria related to tsDMARDs, which was excluded from further analysis. Nine studies of bDMARDs, with 4127 patients, were included for the final analysis. When compared with placebo, both males [odds ratio (OR) 3.14 (95% CI 2.66, 3.70)] and females [OR 2.32 (95% CI 1.82, 2.82)] and younger [OR 4.00 (95% CI 2.50, 6.40)] and older [OR 2.21 (95% CI 1.15, 4.22)] patients presented significantly better responses to bDMARDs. Also, the efficacies were more evident in males [OR 1.89 (95% CI 1.56, 2.30)] and younger [OR 2.07 (95% CI 1.42, 3.02)] patients. Subgroup analysis revealed that the gender difference in efficacy was more obvious in non-radiographic axSpA (nr-axSpA) patients (Pheterogeneity = 0.03, I2 = 78.1%). Moreover, males with radiographic axSpA (r-axSpA) and nr-axSpA shared similar responses to bDMARDs (Pheterogeneity = 0.87, I2 = 0%), while females with r-axSpA showed greater response than those with nr-axSpA (Pheterogeneity = 0.005, I2 = 87.4%).

CONCLUSIONS

The bDMARDs were efficacious in all axSpA patients regardless of gender or age. However, the treatment responses were more evident in male and younger patients. Also, females with r-axSpA had greater responses than those with nr-axSpA, whereas no relevant difference was observed in males, indicating that the gender difference on efficacy was greater in nr-axSpA patients.

[Sex-specific aspects in rheumatology]

Women and men differ in terms of the development and manifestation of inflammatory rheumatic diseases and outcomes as well as with respect to disease perception, health behavior and response to antirheumatic treatment. Sex-specific aspects are increasingly being researched in nearly all medical disciplines to optimize treatment strategies with the aim to improve individual treatment success. This article describes sex differences that can even now be taken into account in rheumatological care.

Difficult-to-treat axial spondyloarthritis patients

Objectives

This study aimed to formulate D2T (difficult to treat) criteria for axial spondyloarthritis (AxSpA) patients and identify the prevalence of D2T patients and their characteristics.

Patients and methods

The cross-sectional study was conducted with 166 AxSpA patients (93 males, 73 females; mean age: 47.1±12.9 years; range, 19 to 78 years) between February 2023 and March 2023. The criteria were based on patients treated according to the European Alliance of Associations for Rheumatology (EULAR) recommendations for AxSpA. Entry criteria were treatment failure to ≥2 biological/targeted synthetic disease-modifying antirheumatic drugs with two different mechanisms of action or ≥3 biological/targeted synthetic disease-modifying antirheumatic drugs. Potential preliminary factors for D2T criteria were analyzed, and the characteristics of the subjects matching D2T criteria were compared with those of others.

Results

One hundred forty-two ankylosing spondylitis patients and 24 nonradiographic AxSpA patients were included in the study. The rate of fulfilling the D2T criteria was 22.9% (n=38) among AxsPA patients treated with biological agents. The potential D2T criteria were met by 23.2% of ankylosing spondylitis and 20.8% of nonradiographic AxSpA patients. Baseline characteristics, such as sex, age, diagnosis age, occupation, and education, of D2T patients were not statistically different from other patients. The prevalence of fibromyalgia was higher in D2T patients (p<0.001). Disease activity indices and acute phase response indicators were higher and quality of life was worse in D2T patients.

Conclusion

There was a considerable amount of AxSpA patients fulfilling the D2T criteria despite new and effective treatment agents.

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

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

Sex dimorphism of IL-17-secreting peripheral blood mononuclear cells in ankylosing spondylitis based on bioinformatics analysis and machine learning

BACKGROUND

Ankylosing spondylitis (AS) with radiographic damage is more prevalent in men than in women. IL-17, which is mainly secreted from peripheral blood mononuclear cells (PBMCs), plays an important role in the development of AS. Its expression is different between male and female. However, it is still unclear whether sex dimorphism of IL-17 contribute to sex differences in AS.

METHODS

GSE221786, GSE73754, GSE25101, GSE181364 and GSE205812 datasets were collected from the Gene Expression Omnibus (GEO) database. Differential expressed genes (DEGs) were analyzed with the Gene Set Enrichment Analysis (GSEA), Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) methods. CIBERSORTx and EcoTyper algorithms were used for immune infiltration analyses. Machine learning based on the XGBoost algorithm model was used to identify the impact of DEGs. The Connectivity Map (CMAP) database was used as a drug discovery tool for exploring potential drugs based on the DEGs.

RESULTS

According to immune infiltration analyses, T cells accounted for the largest proportion of IL-17-secreting PBMCs, and KEGG analyses suggested an enhanced activation of mast cells among male AS patients, whereas the expression of TNF was higher in female AS patients. Other signaling pathways, including those involving metastasis-associated 1 family member 3 (MAT3) or proteasome, were found to be more activated in male AS patients. Regarding metabolic patterns, oxidative phosphorylation pathways and lipid oxidation were significantly upregulated in male AS patients. In XGBoost algorithm model, DEGs including METRN and TMC4 played important roles in the disease process. we integrated the CMAP database for systematic analyses of polypharmacology and drug repurposing, which indicated that atorvastatin, famciclocir, ATN-161 and taselisib may be applicable to the treatment of AS.

CONCLUSIONS

We analyzed the sex dimorphism of IL-17-secreting PBMCs in AS. The results showed that mast cell activation was stronger in males, while the expression of TNF was higher in females. In addition, through machine learning and the CMAP database, we found that genes such as METRN and TMC4 may promote the development of AS, and drugs such as atorvastatin potentially could be used for AS treatment.

Clinical, Laboratory, and Imaging Features Between Men and Women With Axial Spondyloarthritis in a Specialized Center in Argentina

OBJECTIVES

The aims were to estimate the frequency of axial spondyloarthritis (axSpA) in women and to analyze the clinical, laboratory, and imaging differences with respect to men at the time of diagnosis.

METHODS

Consecutive patients older than 18 years with a diagnosis of axSpA admitted to the "Reumacheck" SpA program were included between 2017 and 2022. At baseline, all patients underwent clinical assessment, laboratory tests including C-reactive protein and human leukocyte antigen B27, and imaging (plain radiography and magnetic resonance imaging of sacroiliac joints, and ultrasound of heel entheses). All evaluators were blinded to the results of the other evaluations.

RESULTS

One hundred sixteen patients with a diagnosis of axSpA were included. The frequency at diagnosis in women was 61.55%. In the univariate analysis, the significant differences between women and men at diagnosis of axSpA were good response to nonsteroidal anti-inflammatory drugs, elevated C-reactive protein, New York Criteria (+), enthesis ultrasound (+), years of education, number of swollen joints, erythrosedimentation rate, and the very low frequency of bone bridges in the magnetic resonance imaging of the sacroiliac joints. In the logistic regression analysis, the dependent variable was "men," and the only feature that was independently associated was having radiographic compromise according to the New York criteria (odds ratio, 2.6).

CONCLUSIONS

The frequency of axSpA in women was 61.55%; clinical, laboratory, and imaging differences were observed. Women experienced less radiographic compromise.

The value of a repeat MRI examination of the sacroiliac joints following an inconclusive initial examination

OBJECTIVE

Assess the diagnostic utility of repeat sacroiliac joint (SIJ) magnetic resonance imaging (MRI) examinations following an inconclusive initial examination performed for suspected sacroiliitis.

METHOD

Subjects with > 1 SIJ MRI examinations, an inconclusive first scan and at least 6 months interval between scans, were included. All scans were evaluated for the presence of structural/active SIJ lesions as well as any other pathology. Clinical data was extracted from the patients' clinical files, and any missing data was obtained by a telephone interview. Diagnosis and active/structural scores were compared between first and follow-up examinations (t test).

RESULTS

Seventy-one subjects were included in the study, 77.4% females, mean age 41.0 ± 15 years, mean time interval between exams 30.4 ± 25.24 months. Twelve subjects performed > 2 scans. In only two subjects (2.81%), both females, MRI diagnosis changed from inconclusive to definite sacroiliitis. None of the subjects with > 2 scans had evidence of sacroiliitis in any of the following MRI examinations. Significant differences were observed between the scores of active SIJ lesion of the first and follow-up MRI (1.51/1.62, p = 0.02) but not for scores of structural lesions (1.22/1.68, p = 0.2).

CONCLUSIONS

Repeat SIJ MRI when the first MRI is inconclusive for sacroiliitis is more valuable in ruling out than in securing diagnosis of sacroiliitis. We suggest that when MRI findings are inconclusive, decision-making should be based on clinical data.

Sex-specific disparities in disease activity scores among patients with axial spondyloarthritis and their implications for evaluating the response to tumor necrosis factor alpha inhibitor therapy

BACKGROUND

We aimed to investigate whether there are sex differences in disease activity measures among patients with axial spondyloarthritis (axSpA) and to determine any potential impact on the assessment of treatment responses to tumor necrosis factor alpha inhibitors (TNFi).

METHODS

Using the Korean College of Rheumatology Biologics and Targeted Therapy (KOBIO) registry data, we compared sex differences in changes in the Bath Ankylosing Spondylitis Disease Activity Score (BASDAI) and Ankylosing Spondylitis Disease Activity Score (ASDAS) levels at baseline and one year after TNFi initiation in patients with axSpA.

RESULTS

This study included 1,753 patients with axSpA who started or changed TNFi, of whom 1,343 (76.6%) were male. At baseline, the mean BASDAI and ASDAS scores of all patients were 5.98 and 3.6, respectively. The BASDAI changes between baseline and the one-year follow-up were independently associated with sex (𝛽 = 0.343, p = 0.011), whereas ASDAS was not (𝛽 = 0.079, p = 0.235). When judging the effect of TNFi at one-year of treatment, male patients were more likely to be assessed as effective by the BASDAI-based criterion (ΔBASDAI ≥ 50% or ≥ 2; OR 1.700, 95% CI 1.200-2.406), while the ASDAS-based criterion (ΔASDAS ≥ 1.1) showed no significant difference between sexes (OR 0.993, 95% CI 0.678-1.455), after adjusting for other baseline characteristics.

CONCLUSIONS

The changes in disease activity before and after TNFi use were significantly different between sexes when measured by BASDAI, but not ASDAS. TNFi treatment effects may be interpreted differently between sexes depending on the disease activity measure used.

Sequence of Events in the Pathogenesis of Axial Spondyloarthritis: A Current Review-2023 SPARTAN Meeting Proceedings

PURPOSE OF REVIEW

Over the past two decades, significant progress has been made to untangle the etiology of inflammation and new bone formation (NBF) associated with axial spondyloarthritis (axSpA). However, exact mechanisms as to how the disease initiates and develops remain elusive.

RECENT FINDINGS

Type 3 immunity, centered around the IL-23/IL-17 axis, has been recognized as a key player in the pathogenesis of axSpA. Multiple hypotheses associated with HLA-B*27 have been proposed to account for disease onset and progression of axSpA, potentially by driving downstream T cell responses. However, HLA-B*27 alone is not sufficient to fully explain the development of axSpA. Genome-wide association studies (GWAS) identified several genes that are potentially relevant to disease pathogenesis leading to a better understanding of the immune activation seen in axSpA. Furthermore, gut microbiome studies suggest an altered microbiome in axSpA, and animal studies suggest a pathogenic role for immune cells migrating from the gut to the joint. Recent studies focusing on the pathogenesis of new bone formation (NBF) have highlighted the importance of endochondral ossification, mechanical stress, pre-existing inflammation, and activated anabolic signaling pathways during the development of NBF. Despite the complex etiology of axSpA, recent studies have shed light on pivotal pieces that could lead to a better understanding of the pathogenic events in axSpA.

Factors Associated With Treatment Pathways in Early Axial Spondyloarthritis: A Multistate Analysis of the 10-Year Follow-Up of the DESIR Cohort

OBJECTIVE

Current recommendations for the management of patients with axial spondyloarthritis (axSpA) emphasize the need of an individualized strategy in therapeutic decision-making. The study objectives were to describe therapeutic strategies observed in axSpA, and to assess the factors associated with treatment intensification over time.

METHODS

We included patients with axSpA from the French prospective cohort DESIR (Devenir des Spondylarthropathies Indifférenciées Récentes), with a scheduled 10-year follow-up. A multistate model with 4 ordered treatment states (no treatment, nonsteroidal antiinflammatory drugs [NSAIDs], conventional synthetic disease-modifying antirheumatic drugs [csDMARDs], and tumor necrosis factor inhibitors [TNFi]) was defined, with 6 possible transitions. Restricted mean sojourn times in each state were estimated. Then, predictors of those transitions were assessed by multivariable Cox models.

RESULTS

A total of 686/708 (96.9%) patients who had > 1 visit were analyzed. At cohort entry, 199 (29%) were untreated, 427 (62.2%) were receiving NSAIDs, 60 (8.7%) csDMARDs, and none were receiving TNFi. Over the follow-up period, patients mostly (46.4% of the time) received NSAIDs, followed by TNFi (24.4% of the time). The presence of sacroiliitis on radiographs, inflammatory bowel disease, and articular index were jointly associated with the transition to NSAIDs. Longer duration in the previous state often decreased the hazard of the transition to csDMARDs or TNFi. Worse disease activity outcomes increased the hazard of most transitions.

CONCLUSION

To our knowledge, this was the first study using a multistate model to easily represent different treatment states, detailing the transitions across them and their associated factors. Different time profiles for the management of patients with axSpA were identified, including in those abstaining from treatment up to a significant proportion of patients treated with csDMARDs.

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.

Burden of Other Musculoskeletal Disorders in Latin America and the Caribbean: Findings of Global Burden of Disease Study 2019

OBJECTIVE

To describe the results from the Global Burden Disease (GBD) study 2019 on the burden of other musculoskeletal (MSK) disorders in Latin America and the Caribbean (LAC).

METHODS

In this cross-sectional study, we analyzed data from all LAC region in the GBD study from 1990 to 2019. Other MSK (other than rheumatoid arthritis, osteoarthritis, gout, low back pain, and neck pain) burden was measured as prevalence, mortality, years lived with disability (YLD), and disability-adjusted life (DALY), by year, sex, and country. We show the counts, rates, and 95% uncertainty intervals (95% UI). Joinpoint regression analysis was used to estimate the average annual percentage change (AAPC) from 1990 to 2019. A correlational analysis between the burden parameters and sociodemographic index (SDI) was performed.

RESULTS

In 2019, there were 52.0 million (95% UI, 44.8-60.1 million) individuals with other MSK disorders in LAC. The age-standardized mortality rate in 2019 was 1.2 (95% UI, 0.8-1.6) per 100,000 inhabitants. The AAPC was estimated as 0.1% (95% confidence interval [CI], 0.1-0.2) and 0.2% (95% CI, 0.1-0.3) for prevalence and mortality rates, respectively. The age-standardized DALY rate was 685.4 (95% UI, 483.6-483.6) per 100,000 inhabitants, representing an AAPC of 0.2% (95% CI, 0.1-0.3). The burden was larger in women and the elderly. The SDI was positively correlated with the prevalence of YLD in 2019.

CONCLUSIONS

LAC region has experienced a significant burden of other MSK disorders over the last three decades. To challenge this growing burden, population-based strategies designed to reduce the burden of other MSK and strengthen health systems to contribute effective and cost-efficient care are necessary.

Sex differences in the effectiveness of first-line tumour necrosis factor inhibitors in axial spondyloarthritis: results from the EuroSpA Research Collaboration Network

Objective

Evidence indicates reduced treatment effectiveness of TNFi in women with axial spondyloarthritis (axSpA) compared with men. We aimed to investigate sex differences in treatment response and retention rates over 24 months of follow-up in axSpA patients initiating their first TNFi.

Methods

Data from axSpA patients initiating a TNFi in 1 of 15 registries within EuroSpA collaboration were pooled. We investigated the association of sex with treatment response using logistic regression. The primary outcome was clinically important improvement (CII) at 6 months according to Ankylosing Spondylitis Disease Activity Score with C-reactive protein (CRP) (≥1.1 decrease). We adjusted for age, country and TNFi start year. A secondary outcome was retention rates over 24 months of follow-up assessed by Kaplan-Meier estimator.

Results

In total, 6451 axSpA patients with data on CII were assessed for treatment response; 2538 (39%) were women and 3913 (61%) were men. Women presented at baseline with lower CRP levels but had higher scores on patient-reported outcome measures. At 6 months, 53% of the women and 66% of the men had CII. Women had a lower relative risk of CII compared with men (0.81; 95% CI 0.77 to 0.84). This sex difference was similar in adjusted analysis (0.85; 95% CI 0.82 to 0.88). Retention rates were evaluated in 27 702 patients. The TNFi 6/12/24 months retention rates were significantly lower among women (79%/66%/53%) than men (88%/79%/69%).

Conclusion

Treatment response and retention rates are lower among women with axSpA initiating their first TNFi. Sex differences in treatment effectiveness were present regardless of the outcome measure used for treatment response, and differences in retention rates transpired early and increased as time progressed.

HLA-B*27 and Ankylosing Spondylitis: 50 Years of Insights and Discoveries

PURPOSE OF REVIEW

To commemorate the 50th anniversary of the groundbreaking discovery of a remarkably strong association between HLA-B*27 and ankylosing spondylitis (AS).

RECENT FINDINGS

In addition to HLA-B*27, more than 116 other recognized genetic risk variants have been identified, while epigenetic factors largely remain unexplored in this context. Among patients with AS who carry the HLA-B*27 gene, clonally expanded CD8 + T cells can be found in their bloodstream and within inflamed tissues. Moreover, the α and β chain motifs of these T-cell receptors demonstrate a distinct affinity for certain self- and microbial-derived peptides, leading to an autoimmune response that ultimately results in the onset of the disease. These distinctive peptide-binding and presentation characteristics are a hallmark of the disease-associated HLA-B*27:05 subtype but are absent in HLA-B*27:09, a subtype not associated with the disease, differing by only a single amino acid. This discovery represents a significant advancement in unraveling the 50-year-old puzzle of how HLA-B*27 contributes to the development of AS. These findings will significantly accelerate the process of identifying peptides, both self- and microbial-derived, that instigate autoimmunity. This, in return, will pave the way for the development of more accurate and effective targeted treatments. Moreover, the discovery of improved biomarkers, in conjunction with the emerging technology of electric field molecular fingerprinting, has the potential to greatly bolster early diagnosis capabilities. A very recently published groundbreak paper underscores the remarkable effectiveness of targeting and eliminating disease-causing T cells in a HLA-B*27 patients with AS. This pivotal advancement not only signifies a paradigm shift but also bolsters the potential for preventing the disease in individuals carrying high-risk genetic variants.

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.

A comparison of the clinical characteristics and quality of life of male and female patients with non-radiographic axial spondyloarthritis

OBJECTIVE

The aim of this study was to compare the clinical characteristics and quality of life of male and female patients with non-radiographic axial spondyloarthritis (nraxSpA) to determine the differences and similarities.

PATIENTS AND METHODS

The study included 100 patients, comprising 50 males and 50 females, aged 18-65 years, who presented at the Rheumatology Clinic and were diagnosed with nr-axSpA according to the Assessment of Spondyloarthritis International Society (ASAS) criteria. The data of patient age, gender, body mass index, disease duration, and drugs used were recorded. Disease activity was evaluated with the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), mobility with the Bath Ankylosing Spondylitis Metrology Index (BASMI), functional status with the Bath Ankylosing Spondylitis Functional Index (BASFI), enthesitis with the Maastricht Ankylosing Spondylitis Enthesitis Score (MASES), and quality of life with the Ankylosing Spondylitis Quality of Life (ASQoL). The patients with nr- axSpA were separated into groups as male and female, and the demographic and clinical data were compared.

RESULTS

The mean age of female patients was determined to be statistically significantly higher than that of the male patients (39.04 ± 0.70 vs. 34.28 ± 9.26 years, p:0.014). A statistically greater number of male patients were smokers (p:0.007). The disease duration and time since diagnosis were determined to be significantly longer in females than in males (p:0.029, p:0.004). Peripheral arthritis was determined at a significantly higher rate in females (p < 0.001). The MASES score was 2.66 ± 3.46 in females and 0.52 ± 1.03 in males, and the difference was statistically significant (p < 0.001). The BASDAI score was significantly higher in females (3.74 ± 2.35) than in males (2.88 ± 1.95) (p:0.05). No statistically significant difference was determined between the two groups in respect of BASFI, BASMI, ASQoL, and other parameters.

CONCLUSION

The results showed older age, longer disease duration and time to diagnosis, higher rates of peripheral arthritis, and higher MASES and BASDAI scores in the female patients. Thus, there are some differences between male and female patients. Further studies should determine what kind of changes these differences will make in the clinical status, follow-up and treatment of patients.

Influence of Sex on Early Axial Spondyloarthritis: A Six-Year Longitudinal Analysis From a Large National Cohort

OBJECTIVE

The objective was to determine sex differences in disease outcomes in recent axial spondyloarthritis (SpA) over time.

METHODS

We analyzed the first 6 years of follow-up of the prospective French multicenter DESIR cohort. Patients analyzed had <3 years of disease, were naive to disease-modifying antirheumatic drugs, and fulfilled the Assessment of SpondyloArthritis international Society classification criteria for axial SpA. Disease activity (Ankylosing Spondylitis Disease Activity Score [ASDAS] using the C-reactive protein [CRP] level), patient global assessment (PtGA), CRP level, and radiographic sacroiliitis were compared between men and women (self-reported sex) by linear and logistic mixed-effects models. Models were created for trajectories of disease activity over 6 years in men and women, using k-means.

RESULTS

Of 494 patients analyzed (mean ± SD age 31.9 ± 7.5 years, symptoms duration 20.7 ± 11.7 months), 50.4% were men. Over 6 years of follow-up, both men and women showed clear improvements in ASDAS-CRP, PtGA, and CRP level. Women had higher ASDAS-CRP and PtGA over time compared to men (both P < 0.0001) with overall similar CRP levels (P = 0.089), whereas structural damage increased more in men (P < 0.0001). One-third of both men (33%) and women (34%) belonged to persistent high/very high disease activity trajectories, but ASDAS-CRP was globally higher in women in these trajectories.

CONCLUSION

In early axial SpA, clinical outcomes (disease activity and symptoms) were worse in women than men over 6 years of follow-up, whereas CRP was similar and structural damage was more frequent in men. Although similarly distributed, disease activity scores were higher in women in high/very high disease activity trajectories. Sex appears to be an important contextual factor in axial SpA.

Physical function and sex differences in radiographic axial spondyloarthritis: a cross-sectional analysis on Bath Ankylosing Spondylitis Functional Index

BACKGROUND

Physical function is an important determinant of health-related quality of life in radiographic axial spondyloarthritis patients (r-axSpA). To improve the basis of effective healthcare efforts, we aimed to investigate which demographic and disease-related factors that influence Bath Ankylosing Spondylitis Functional Index (BASFI) in r-axSpA patients overall and stratified by sex. Furthermore, we sought to explore differences between sexes regarding separate BASFI questions and also to explore which factors that may contribute to these differences.

METHODS

This observational cross-sectional study included patients fulfilling the modified New York criteria for Ankylosing Spondylitis. Patients were assessed with 66/68 joint count and Bath Ankylosing Spondylitis Metrology Index (BASMI) measurements. Lateral X-rays were performed for Modified Stoke Ankylosing Spondylitis Spinal Score (mSASSS). Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), Ankylosing Spondylitis Disease Activity Score (ASDAS)-C-Reactive Protein (CRP), and BASFI were registered. Multivariable linear regression analyses were used to investigate which factors that associate with BASFI.

RESULTS

A total of 353 r-axSpA patients were included, mean age 52.2 ± 12.7 years, 62.3% males. No significant sex difference was seen in BASFI scores (2.7 ± 2.0 in males vs 2.9 ± 2.1 in females). Age, body mass index, ASDAS-CRP, BASMI or mSASSS, fatigue, and tenderness were found to associate independently with BASFI in different models (R2 0.53-0.63). Investigation of separate BASFI questions revealed that the ability to look over shoulder was worse in males than females (mean 4.43 ± 3.37 vs 3.74 ± 3.06, p = 0.05) and most strongly correlated with mSASSS and BASMI among separate BASFI questions (r = 0.53, p < 0.001; r = 0.62, p < 0.001). The ability to climb stairs was worse in females than males (mean 2.49 ± 2.77 vs 1.54 ± 2.32, p < 0.001).

CONCLUSIONS

No difference between male and female r-axSpA patients was seen in BASFI despite significant sex differences in BASMI, mSASSS, and CRP levels. Our results underline the impact of fatigue and tenderness on BASFI. The ability to climb stairs without a handrail was scored worse among females compared to males. Furthermore, the ability to look over the shoulder was worse in males than females and closely related to spinal mobility and structural spinal changes.

Relationship between sex and clinical and imaging features of early axial spondyloarthritis: results from a 48 month follow-up (Italian arm of the SPondyloArthritis Caught Early (SPACE) study)

OBJECTIVES

To assess the association between sex and clinical and disease activity indices, and X-rays and magnetic resonance imaging (MRI) features, in early-stage axial spondyloarthritis (axSpA).

METHOD

Baseline data analysis was conducted on the Italian SPACE cohort, including patients with chronic back pain (duration ≥ 3 months and ≤ 2 years; onset < 45 years). Patients underwent MRI and X-rays of the sacroiliac joints (SIJs) to establish the diagnosis of axSpA, according to Assessment of SpondyloArthritis international Society criteria and physician's judgement. Clinical features, disease activity and functional indices, and images were collected at baseline and yearly during 48 months. Spinal and SIJ X-rays and MRI images were scored by two readers following Spondyloarthritis Research Consortium of Canada (SPARCC), modified Stoke Ankylosing Spondylitis Spinal Score, and modified New York criteria. Characteristics of axSpA patients according to sex (male/female) were compared over time using descriptive statistics.

RESULTS

Ninety-one patients had axSpA (83.5% non-radiographic; 16.5% radiographic); 47.3% were male. Males were younger, with shorter duration of axial symptoms, and more frequently had HLA-B27 positivity, radiographic sacroiliitis with a bilateral/symmetric pattern, and more signs of spondylitis. Females more frequently showed peripheral/entheseal involvement and the non-radiographic phenotype. Males showed increased pelvic/spinal radiographic progression and more often had active sacroiliitis on MRI. Although the frequency of inflammatory corner lesions did not differ between males and females, localization varied, with more cervical/thoracic MRI-spine lesions in females and more lumbar lesions in males. We observed a significant downward trend of SPARCC SIJ/spine scores in all patients, irrespective of sex. More fat lesions were observed on MRI-spine in females and on MRI-SIJ in males.

CONCLUSION

Sex was associated with distinct axSpA features: females showed low-grade radiographic sacroiliitis and spinal progression, and a higher prevalence of cervical and thoracic spine MRI signs.

Sleep behaviour differs in women and men with psoriatic arthritis and axial spondyloarthritis with impact on quality of life and depressive symptoms

OBJECTIVES

Axial spondyloarthritis (axSpA) and psoriatic arthritis (PsA) may have a profound impact on sleep and health-related quality of life. The aim of this study was to assess sleep quality and quality of life and determine associated factors in patients treated with spondyloarthritides (SpA).

METHODS

Cross-sectional questionnaire-based assessment of sleep behaviour, quality of life, functional impairment and depression (Regensburg Insomnia Scale, WHO Quality of Life questionnaire, Funktionsfragebogen Hannover questionnaire, Beck Depression Inventory II, Patient health questionnaire 9) and retrospective medical chart analysis of a monocentric cohort of 330 patients with SpA (n=168 PsA and n=162 axSpA).

RESULTS

46.6% of patients with SpA demonstrated abnormal sleep behaviour. Linear regression models showed HLA-B27 positivity, Bath Ankylosing Spondylitis Disease Activity Index, depressive symptoms, functional capacity and disease duration to be predictive of insomnia symptoms in axSpA, respectively, depressive symptoms, female sex and Disease Activity Score 28 in patients with PsA. Patients with unrestful sleep had a significantly reduced health-related quality of life (p<0.001) as well as significantly more depressive symptoms (p<0.001). Satisfaction with health was rated significantly lower (p<0.001), indicating poor sleep as a burden on general well-being.In particular, female patients had a significantly worse sleep quality with a prolonged sleep latency (p=0.009), increased sleep disturbances (p=0.014) and unrestful sleep (p<0.001) as well as a reduced physical and mental health-related quality of life (p=0.015, p<0.001) and more depressive symptoms (p=0.015).

CONCLUSION

Despite treatment, many patients with SpA demonstrate abnormal sleep behaviour with symptoms of insomnia and a reduced quality of life with significant differences between male and female patients. An interdisciplinary and holistic approach may be needed to address unmet needs.

Sex differences in cardiovascular and disease-related features in axial spondyloarthritis. A multicenter study of 912 patients

OBJECTIVES

To determine the potential impact of sex-specific disease-related characteristics on cardiovascular (CV) disease in axial spondyloarthritis (axSpA).

METHODS

Cross-sectional study of the Spanish AtheSpAin cohort to study CV disease in axSpA. Data on carotid ultrasound and CV disease and disease-related features were collected.

RESULTS

611 men and 301 women were recruited. Classic CV risk factors were significantly less prevalent in women, who also showed a lower frequency of carotid plaques (p = 0.001), lower carotid intima-media thickness (IMT) values ​​(p<0.001) and CV events (p = 0.008). However, after adjustment for classic CV risk factors, only the differences with respect to carotid IMT remained statistically significant. Women showed higher ESR at diagnosis (p = 0.038), and more active disease (ASDAS, p = 0.012, and BASDAI, p<0.001). They had shorter disease duration (p<0.001), lower prevalence of psoriasis (p = 0.008), less structural damage (mSASSS, p<0.001), and less mobility limitation (BASMI, p = 0.033). To establish whether these findings could lead to sex differences in CV disease burden, we compared the prevalence of carotid plaques in men and women with the same level of CV risk stratified according to the Systematic Coronary Risk Evaluation (SCORE). Men included in the low-moderate CV risk SCORE category had more carotid plaques (p = 0.050), along with longer disease duration (p = 0.004), higher mSASSS (p = 0.001) and psoriasis (p = 0.023). In contrast, in the high-very high-risk SCORE category, carotid plaques were observed more frequently in women (p = 0.028), who were characterized as having worse BASFI (p = 0.011), BASDAI (p<0.001) and ASDAS (p = 0.027).

CONCLUSION

Disease-related features may influence the expression of atherosclerosis in patients with axSpA. This may be especially applicable to women at high CV risk, characterized by greater disease severity and more severe subclinical atherosclerosis than men, suggesting a stronger interaction between disease activity and atherosclerosis in women with axSpA.

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.

Axial Spondyloarthritis and Diagnostic Challenges: Over-diagnosis, Misdiagnosis, and Under-diagnosis

PURPOSE OF REVIEW

This article aims to review the challenges in axial spondyloarthritis diagnosis and identify the possible contributing factors.

RECENT FINDINGS

The inability to reach an accurate diagnosis in a timely fashion can lead to treatment delays and worse disease outcomes. The lack of validated diagnostic criteria and the misuse of the currently available classification criteria could be contributing. There is also significant inter-reader variability in interpreting images, and the radiologic definitions of axial spondyloarthritis continue to be re-defined to improve their positive predictive value. The role of inflammatory back pain features, serologic biomarkers, genetics, and their diagnostic contribution to axial spondyloarthritis continues to be investigated. There is still a significant amount of delay in the diagnosis of axial spondyloarthritis. Appreciating the factors that contribute to this delay is of utmost importance to close the gap. It is similarly important to recognize other conditions that may present with symptoms that mimic axial spondyloarthritis so that misdiagnosis and wrong treatment can be avoided.

Does gender influence outcome measures similarly in patients with spondyloarthritis? Results from the ASAS-perSpA study

OBJECTIVES

To investigate the influence of gender on disease outcomes in patients with spondyloarthritis (SpA), including across SpA subtypes.

METHODS

Data from 4185 patients of 23 countries with a diagnosis of axial SpA (axSpA), peripheral SpA (pSpA) or psoriatic arthritis (PsA) from the Assessment of SpondyloArthritis International Society (ASAS)-perSpA study were analysed. Associations between gender and disease activity (Ankylosing Spondylitis Disease Activity Score (ASDAS), Bath Ankylosing Spondylitis Disease Activity Score (BASDAI), C-reactive protein (CRP)), function (Bath Ankylosing Spondylitis Functional Index (BASFI)) and overall health (ASAS Health Index (ASAS HI), European Quality of Life Five Dimension (EQ-5D)) outcomes were investigated. Multilevel multivariable linear mixed models adjusted for relevant confounders (and stratified by disease subtype in case of a relevant interaction) were used.

RESULTS

In total, 65%, 10% and 25% of patients had axSpA, pSpA and PsA, respectively. axSpA was more frequent in males (68%), whereas pSpA and PsA were more frequent in females (53% and 52%, respectively). A significant interaction between gender and disease subtype was found for ASDAS, BASDAI and BASFI. While being female independently contributed to higher BASDAI across the three disease subtypes (with varying magnitude), female gender was only associated with higher ASDAS in pSpA (β (95% CI): 0.36 (0.15 to 0.58)) and PsA (0.25 (0.12 to 0.38)) but not in axSpA (0.016 (-0.07 to 0.11)). No associations were observed between gender and CRP levels. Female gender was associated with higher ASAS HI and EQ-5D, without differences across disease subtype.

CONCLUSION

Female gender is associated with less favourable outcome measures across the SpA spectrum. However, while female gender influences BASDAI across the three subtypes, ASDAS is associated with gender only in pSpA and PsA but not in axSpA. Therefore, ASDAS is an appropriate instrument both for females and males with axSpA.

Sex- and gender-related differences in psoriatic arthritis

Psoriatic arthritis (PsA) is an inflammatory musculoskeletal disease with a chronic, progressive course. Various aspects of PsA, including its clinical features, disease course and response to treatment, are influenced by sociodemographic characteristics of the patient. This includes patient sex, the biological attributes associated with being male or female, and gender, a sociocultural construct that comprises attitudes, traits and behaviours associated with being a man or a woman. An understanding of sex- and gender-related differences in PsA, as well as their underlying mechanisms, is therefore important for individualized care. In this narrative review, the influence of sex and gender on PsA manifestation and course, patient function and quality of life, and their association with comorbidities are described. Sex- and gender-related disparities in response to advanced therapies and their potential underlying mechanisms are delineated. Differences in pathophysiological mechanisms between male and female patients including genetics, immune and hormonal mechanisms are discussed. Finally, fertility and pregnancy outcomes in PsA are outlined. By adopting sex and gender lenses, this review is aimed at highlighting key differences between male and female patients with PsA and uncovering mechanisms underlying these differences, ultimately promoting individualized care of men and women with PsA and informing future research in this area.

The role of LCN2 and LCN2-MMP9 in spondylitis radiographic development: gender and HLA-B27 status differences

Background

Male HLA-B27-positive radiographic-axial spondyloarthritis (r-axSpA) patients are prone to have severe spinal radiographic progression, but the underlying mechanisms are unclear. We recently showed that persistently elevated Lipocalin 2 (LCN2; L) reflects sacroiliac joint (SIJ) inflammation. LCN2 binds to MMP9. Concomitant elevation of L and LCN2-MMP9 (LM) was detected in many inflammatory diseases. We asked whether L and LM play similar roles in r-axSpA pathogenesis.

Methods

We analyzed 190 axSpA patients (123 radiographic and 67 non-radiographic axSpA) who had no detectable circulating Oncostatin M, to avoid complications due to cross-talk between pathways. L and LM levels from a single blood sample of each patient were measured and were correlated with MRI and modified stoke AS (mSASS) scoring. Association of elevated L (L+) or concurrent L+ and elevated LM (LM+) patterns with B27 status and gender were assessed.

Results

In L+LM+ axSpA patients, both L and LM levels correlated with MRI SPARCC SIJ scores, but only LM levels correlated with MRI Berlin Spine Scores, suggesting LM is a biomarker for both SIJ and spinal inflammation. Among patients with minimal spinal ankylosis (mSASSS < 10), 65% of male r-axSpA patients are L+LM+, while 30% and 64% of female patients are L+LM+ and L+, respectively, supporting the role of LM with disease progression. In B27+ L+LM+ male patients, both L and LM (but not CRP) levels correlate with mSASSS. B27 positivity and maleness have additive effects on spondylitis progression, suggesting concurrent high L and LM elevations are associated with B27+ male patients having more significant radiographic damage. L+ B27-negative male patients or L+ female patients are more likely to have milder disease.

Conclusion

L and LM are informative biomarkers for SIJ and spinal inflammation, as well as for ankylosing development in r-axSpA patients. Distinctive L+LM+ or L+ patterns not only could distinguish clinically aggressive vs milder course of disease, respectively, but also provide an explanation for B27-positive male patients being the most susceptible to severe ankylosis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13075-022-02854-2.

Baseline Characteristics and Treatment Response to Ixekizumab Categorised by Sex in Radiographic and Non-radiographic Axial Spondylarthritis Through 52 Weeks: Data from Three Phase III Randomised Controlled Trials

Objectives

Assess baseline characteristics and treatment response to ixekizumab (IXE) categorised by sex in patients with radiographic axial spondyloarthritis (r-axSpA) and non-radiographic axSpA (nr-axSpA) up to 52 weeks.

Methods

Data were analysed from three randomised controlled trials of IXE through 52 weeks. Patients fulfilled ASAS classification criteria for r-axSpA or nr-axSpA and were randomised to receive 80 mg subcutaneous administration of IXE every 2 weeks (Q2W) or 4 weeks (Q4W), or placebo (16 weeks COAST-V/W; 52 weeks COAST-X). Baseline characteristics and treatment outcomes were assessed. Patients were categorised by sex; methods included non-responder imputation for categorical variables, and modified baseline observation carried forward for continuous efficacy variables.

Results

At presentation, female patients had higher disease burden as reflected by significantly higher spinal pain at night, fatigue scores and pain/swelling in joints other than the neck, back or hip. ASAS40 response rate with the approved label dose, IXEQ4W, was achieved in 39% of male patients with r-axSpA by week 16, and 44% by week 52. For female patients, 16.7% and 33.3% achieved ASAS40 at week 16 and 52, respectively. In nr-axSpA, 46% of male patients achieved ASAS40 at week 16 and 30% at week 52. In total, 23.9% of female patients achieved ASAS40 at week 16, and 30.4% at week 52.

Conclusions

This analysis demonstrates that for the axSpA disease spectrum, female patients present with higher disease burden. Following treatment with IXE, there is a higher proportion of male responders up to 16 weeks, while female patients show less robust responses for the first 16 weeks but larger responses from weeks 16 through 52.

Trial Registration Numbers

NCT02696785, NCT02696798 and NCT02757352.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12325-022-02132-2.

Nonradiographic axial spondyloarthritis: expanding the spectrum of an old disease: A narrative review

Nonradiographic axial spondyloarthritis (nr-axSpA) represents a distinct phenotype within the spectrum of axial spondyloarthritis (axSpA), which is characterized by a range of clinical manifestations. Despite a high disease burden that is comparable to ankylosing spondylitis (also known as radiographic axSpA), there is an unmet need to recognize and effectively manage patients with active nr-axSpA.A targeted literature search was conducted in OVID (MEDLINE and Embase databases) to identify articles on nr-axSpA, including its definition, demographics, epidemiology, burden, diagnosis, clinical presentation, and treatment guidelines.The lack of adequate epidemiological data and incomplete understanding of nr-axSpA among rheumatologists and nonrheumatologists contributes to delayed referrals and diagnosis. This delay results in a substantial burden on patients, physically and psychologically, and the healthcare system. Targeted therapies, such as biologics, including inhibitors of tumor necrosis factor or interleukin-17A, have been approved and utilized for the management of nr-axSpA, and other novel therapeutics with different mechanisms of action are in development. Raising awareness among US internists regarding the prevalence of nr-axSpA, disease burden, clinical presentation, diagnostic tools, and available treatments is important for improved disease management.Future clinical investigations focusing on the development of markers that aid early diagnosis and predict treatment response may also improve the management of nr-axSpA. This review provides an overview of nr-axSpA with the aim of raising awareness of the disease among US internists, with an overarching goal to contribute toward the improved recognition and timely referral of these patients to rheumatologists for diagnosis and management.

Does Gender Impact a Diagnosis of Ankylosing Spondylitis?

Objective

The study objective was to explore differences in ankylosing spondylitis (AS) diagnosis experiences between men and women by examining the coding of health events over the 2 years preceding AS diagnosis.

Methods

Claims data (January 2006–April 2019) from the MarketScan databases were examined. Patients who had received two or more AS diagnoses at least 30 days apart and had at least 2 years of insurance enrollment before their first AS diagnosis were analyzed. Men were matched 1:1 to women by age, diagnosis date, insurance type, and enrollment duration. Health events (diagnosis and provider codes) were examined over 2 years before AS diagnosis and stratified by gender. Data were analyzed using univariate χ² tests.

Results

Among 7744 patients, 274 of 1906 AS‐related codes showed statistically significant differences between men and women. Women received more diagnosis codes than men across diagnoses and providers; the largest difference in diagnosis codes among women versus men was in peripheral symptom coding (57.7% vs. 43.9%, respectively). More women than men received diagnosis codes for depression (21.2% vs. 9.8%) and other musculoskeletal symptoms (52.8% vs. 40.0%); only gout was more common in men (6.5%) than in women (2.2%). Among men, backache codes gradually increased 12 months before AS diagnosis, whereas axial and sacroiliitis coding increased sharply immediately before diagnosis. The greatest difference in physician types visited was for rheumatologists: 64.2% of women had visits compared with 45.1% of men.

Conclusion

Further investigation into the dissimilarities in diagnostic experiences between men and women is needed to determine whether differences are due to disease phenotype or potential cognitive bias influencing diagnostic decision‐making.

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.

Characterising axial psoriatic arthritis: correlation between whole spine MRI abnormalities and clinical, laboratory and radiographic findings

OBJECTIVE

To describe the prevalence of inflammatory and structural lesions using whole spine MRI in patients with psoriatic disease, and to assess their correlation with clinical features and with axial spondyloarthritis (axSpA) classification criteria.

METHODS

This retrospective analysis included patients with whole spine and sacroiliac joints (SIJ) MRI, selected from 2 populations: (1) active psoriatic arthritis (PsA), irrespective of axial symptoms; (2) psoriasis with confirmed or suspected PsA and axSpA symptoms. MRI spondylitis and/or sacroiliitis (MRI-SpA) was defined according to Assessment of Spondyloarthritis International Society (ASAS) consensus and by radiologist impression. Agreement between MRI-SpA and different inflammatory back pain (IBP) definitions (Berlin/ASAS/rheumatologist criteria) and the axSpA classification criteria were calculated considering MRI as gold standard. Logistic regression determined MRI-SpA-associated factors.

RESULTS

93 patients were analysed (69.9% PsA; 30.1% psoriasis). Back pain was present in 81.7%, defined as IBP in 36.6%-57%. MRI-SpA was found in 9.7% of patients by ASAS definition and in 12.9% by radiologist impression, of which 25% had isolated spondylitis.Low agreement was found between the three IBP definitions and MRI-SpA. Rheumatologist criteria was the most sensitive (50%-55.6%) while ASAS and Berlin criteria were the most specific (61.9%-63%). axSpA criteria had poor sensitivity for MRI-SpA (22.2%-25%). Late onset of back pain or asymptomatic patients accounted for most cases with MRI-SpA not meeting axSpA or IBP criteria. Male sex was associated with MRI-SpA (OR 6.91; 95% CI 1.42 to 33.59) in multivariable regression analysis.

CONCLUSION

Prevalence of MRI-defined axSpA was low and showed poor agreement with IBP and axSpA criteria.

The disease burden of axial spondyloarthritis: through a gendered lens

INTRODUCTION

Axial spondyloarthritis (axSpA) affects patients' health-related quality of life (HRQoL). Prior studies have documented gender differences in axSpA across the disease spectrum. Our study aims to assess gender differences on the effects of axSpA on patients' HRQoL.

METHOD

A secondary qualitative thematic analysis was conducted using data from in-depth interviews (n = 24) of patients with a rheumatologist-confirmed axSpA diagnosis. This analysis focused on gender and HRQoL themes including activity, occupation, sleep, healthcare system, mental health, medication usage, and relationships.

RESULTS

While men on average waited a year longer than women to tell healthcare providers about symptoms (2.5 years men versus 1.6 years women), the interval between first report of symptoms to diagnosis was ~ 2 years longer for women relative to men (7.5 women versus 9.3 years men). Women and men with axSpA shared more similarities than differences regarding the impact of disease on HRQoL including (1) physical health, (2) limited mobility, (3) occupation, (4) sleep, (5) healthcare system obstacles, (6) mental health, (7) medication usage, and (8) relationships. Some women reported being dismissed by doctors due to their gender, and some described the pain experienced during pregnancy and complications during birth.

CONCLUSIONS

axSpA adversely impacts HRQoL regardless of gender, but women seeking care for axSpA may experience greater challenges reaching a diagnosis. It is essential that providers recognize impaired HRQoL among men and women with axSpA. Future studies with larger sample sizes are needed to identify aspects of HRQoL to adequately address people with axSpA. Key Points • While men waited on average a year longer to tell their healthcare provider about their symptoms, the diagnostic delay is 2 years longer for women. • Women and men with axSpA have similar experiences regarding impacts on their health-related quality of life. • Some women describe difficulty during pregnancy and being dismissed by doctors due to their gender.

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.

The Need for SPACE to Plan the Future for Spondyloarthritis

"Lifestyle Factors and Disease Activity Over Time in Early Axial Spondyloarthritis: The SPondyloArthritis Caught Early (SPACE) Cohort" by Exarchou et al aimed at looking at the importance of baseline lifestyle factors of BMI, smoking, and alcohol consumption (AC) on disease activity in recent-onset axial spondyloarthritis (axSpA).¹ Does this study add to our knowledge of the natural history of axSpA?

Determining factors related to impaired spinal and hip mobility in patients with axial spondyloarthritis: longitudinal results from the DESIR cohort

Objective

To investigate the determinants of impaired spinal and hip mobility in patients with early axial spondyloarthritis (axSpA).

Methods

Five-year longitudinal data from the DEvenir des Spondyloarthrites Indifférenciées Récentes (DESIR) cohort were analysed. Associations were investigated using generalised estimating equations, using Bath Ankylosing Spondylitis Metrology Index (BASMI) linear or each of the five components of BASMI as dependent variables, and clinical and demographic variables as independent variables in univariable models. Multivariable analyses were performed, adjusting for potential confounders.

Results

Data from 644 patients and 5152 visits were analysed. Higher BASMI values were independently and positively associated with Ankylosing Spondylitis Disease Activity Score C reactive protein (ASDAS-CRP) (adjusted B (adjB)=0.21; 95% CI=0.15 to 0.28), MRI spinal inflammation score (adjB=0.11; 95% CI=0.04 to 0.19), enthesitis score (adjB=0.02; 95% CI=0.01 to 0.04) and age (adjB=0.02; 95% CI=0.01 to 0.03). All BASMI components were independently associated with ASDAS-CRP and MRI spinal inflammation, except for maximal intermalleolar distance (reflecting hip mobility), which was not associated with MRI spinal inflammation.

Conclusion

In early axSpA, spinal mobility impairment is independently determined by clinical disease activity, MRI spinal inflammation, enthesitis and age. The influence of spinal inflammation prevails in early axSpA, as opposed to spinal structural damage, which may become more relevant in later disease stages.

Genetics, Epigenetics, and Gender Impact in Axial-Spondyloarthritis Susceptibility: An Update on Genetic Polymorphisms and Their Sex Related Associations

Spondyloarthritis (SpA) is a group of chronic inflammatory rheumatic disease that can be divided into predominantly axial or predominantly peripheral involvement, with or without associated psoriasis, inflammatory bowel disease or previous infection. Axial SpA (axSpA) encompasses ankylosing spondylitis (AS) with radiological sacroiliitis, and a type without radiographic sacroiliitis, called “non-radiographic axial SpA” (nr-axSpA). Males and females show large differences in their susceptibility to SpA, such as distinctions in clinical patterns, phenotypes and in therapeutical response, particularly to TNF inhibitors (TNFi). Several studies indicate that AS women have doubled risk to failure TNFi compared with males. This diversity in drugs’ efficacy among women and men may be caused by differences in the balance of sex hormones and in gene-specific expression likely triggered by X-chromosome instability and gene-specific epigenetic modifications. Evidence reported that polymorphisms in microRNAs on X- and other chromosomes, such as miR-146a, miR-155, miR-125a-5p, miR-151a-3p and miR-22-3p, miR-199a-5p could be involved in the different clinical presentation of SpA, as well as disease activity. In addition, association with non−response to TNFi treatment and presence of IRAK3 and CHUCK genes in SpA patients was recently detected. Finally, polymorphisms in genes involved in IL-23/IL-17 pathway, such as in drug pharmacodynamics and pharmacokinetics may have a role in response to TNFi, IL17i, and IL23i. A major understanding of genomic variability could help in the development of new therapeutic targets or in taking advantages of different mechanisms of action of biological drugs. Moving from the multifactorial etiology of disease, the present review aims at evaluating genetic and epigenetic factors and their relationship with sex and bDMARDs response, helping to investigate the different expression among males and females of genes on X- and other chromosomes, as well as mi-RNA, to highlight relationships between sex and occurrence of specific phenotypes and symptoms of the disease. Moreover, the role of the epigenetic modification in relation to immune-regulatory mechanisms will be evaluated.

Factors associated with remission at 5-year follow-up in recent onset axial spondyloarthritis: results from the DESIR cohort

Objective

The factors contributing to long-term remission in axial SpA (axSpA) are unclear. We aimed to characterize individuals with axSpA at the 5-year follow-up to identify baseline factors associated with remission.

Methods

We included all patients from the DESIR cohort (with recent-onset axSpA) with an available Ankylosing Spondylitis Disease Activity Score–CRP (ASDAS-CRP) at 5-year follow-up. Patients in remission (ASDAS-CRP < 1.3) were compared with those with active disease by demographic, clinical, biological and imaging characteristics. A logistic model stratified on TNF inhibitor (TNFi) exposure was used.

Results

Overall, 111/449 patients (25%) were in remission after 5 years. Among those never exposed to TNFi, 31% (77/247) were in remission compared with 17% (34/202) of those exposed to TNFi. Patients in remission after 5 years were more likely to be male, HLA-B27+, have a lower BMI, and a higher education level. Baseline factors associated with 5-year remission in patients never exposed to TNFi included lower BASDAI [adjusted odds ratio (OR_a) 0.9, 95% CI: 0.8, 0.9) and history of peripheral arthritis (OR_a 2.1, 95% CI: 1.2, 5.3). In those exposed to TNFi, remission was associated with higher education level (OR_a 2.9, 95% CI: 1.6, 5.1), lower enthesitis index (OR_a 0.8, 95% CI: 0.7, 0.9), lower BASDAI (OR_a 0.9, 95% CI: 0.9, 0.9) and lower BMI (OR_a 0.8, 95% CI: 0.7, 0.9).

Conclusion

This study highlights the difficulty in achieving 5-year remission in those with recent-onset axSpA, especially for the more active cases, despite the use of TNFi. Socio-economic factors and BMI are implicated in the outcome at 5 years.

Age at onset in axial spondyloarthritis around the world: data from the ASAS-PerSpA study

Objective

Age at onset is useful in identifying chronic back patients at an increased risk of axial SpA (axSpA). However, the majority of data on which the criterion of age at onset <45 years is based originates from Europe. Therefore it is unknown if this criterion applies in other parts of the world. We aimed to assess the age at onset of axSpA and its relationship with HLA-B27 and gender across the world.

Methods

Analyses were applied to patients from 24 countries across the world with an axSpA diagnosis and known age at onset of axial complaints. Cumulative probability plots were used to display the cumulative distribution of age at onset of axial symptoms. Linear regression models were built to assess the effect of HLA-B27 and gender on age at onset of axial symptoms.

Results

Of 2579 axSpA patients, 92% had an age at onset of axial symptoms <45 years, with only small variations across the geographical regions [Asia, n = 574 (94%); Europe and North America, n = 988 (92%); Latin America, n = 246 (89%); Middle East and North Africa, n = 771 (91%)]. Age at onset of axial symptoms was consistently lower in HLA-B27-positive patients {median 25 years [interquartile range (IQR) 19–32] vs 31 [IQR 22–39]} and male patients [median 25 years (IQR 19–33) vs 28 (IQR 21–37)], but in multivariable models an additional statistically significant effect of male gender independent of HLA-B27 was only found in Asia.

Conclusion

Around the world, the great majority of axSpA patients had an age at onset of axial disease of <45 years, with HLA-B27 and male gender associated with earlier disease onset.

Clinical characteristics of non-radiographic axial spondyloarthritis: Results of the Korean Nonradiographic Axial SPondyloArthritis (KONASPA) data

AIM

To evaluate clinical characteristics and natural history of non-radiographic axial spondyloarthritis (nr-axSpA) using KOrean Nonradiographic Axial SPondyloArthritis (KONASPA) data.

METHODS

Data were collected from 11 centers in South Korea. A total of 278 patients with nr-axSpA from January 2018 to July 2020 were included. Demographic data, clinical features, comorbidities, disease activity, medications, and laboratory results were collected.

RESULTS

Mean age at symptom onset was 28.2 ± 14.2 years. Of 278 patients, 152 (54.7%) were male. Mean Bath Ankylosing Spondylitis Disease Activity Index at diagnosis was 3.5 ± 2.1. Dyslipidemia was the most common comorbidity (8.4%), followed by hypertension (6.1%). Mean age at diagnosis of nr-axSpA was older in female patients than in male patients (31.8 ± 15.8 years vs 24.9 ± 12.0 years, P < 0.001). Enthesitis and uveitis were more frequently found in female patients than in male patients. Thirty-one (11.1%) participants with nr-axSpA progressed to ankylosing spondylitis. The median follow-up duration was 48 months. In multivariable Cox regression analysis, age at symptom onset (hazard ratio [HR] 0.93, 95% confidence interval (CI) 0.88-0.97, P = 0.006), body mass index (BMI) (HR 1.24, 95% CI 1.06-1.44, P = 0.005) and sacroiliitis grade (HR 1.86, 95% CI 1.19-2.92, P = 0.006) were associated with progression to ankylosing spondylitis.

CONCLUSIONS

Results of nationwide data revealed that women with nr-axSpA showed a late disease onset and more extra-articular manifestations than men. Young age at symptom onset, high BMI, and presence of radiographic sacroiliitis at diagnosis were risk factors for progression to AS.

Gender Differences in Disease Activity and Impact in Axial Spondyloarthritis

Ankylosing spondylitis (AS), characterized by inflammatory back pain and sacroiliitis on radiography, was traditionally considered a condition predominant in men. Since the introduction of the 2009 Assessment in Spondyloarthritis international Society classification criteria¹ aiming to facilitate earlier classification of cases without radiographic sacroiliitis, more women have been classified as having axial spondyloarthritis (axSpA).