Association of body mass index on disease activity in axial spondyloarthritis: systematic review and meta-analysis

Alarming serum antiprotease levels in axial spondyloarthritis

Objectives

The objective was to assess the serum levels of secretory leukocyte protease inhibitor (SLPI) and elafin in individuals diagnosed with axial spondyloarthritis (AxSpA) and analyze their diagnostic significance and correlation with disease activity.

Patients and methods

The case-controlled, cross-sectional study was conducted between August 2021 and April 2023. Sixty patients diagnosed with AxSpA (n=60) were classified according to imaging results as nonradiographic AxSpA (nr-AxSpA [n=30]; 15 males, 15 females; median age: 30 years; range, 27.6 to 34.1 years) and radiographic AxSpA (r-AxSpA [n=30]; 19 males, 11 females; median age: 33 years; range, 30.6 to 38.1 years), forming two patient groups (the nr-axSpA and r-axSpA groups). A total of 30 age- and sex-matched healthy controls (16 females, 14 males; median age: 33 years; range, 29.2 to 37.1 years) were included. Demographic data, laboratory, and clinical characteristics of the participants were recorded.

Results

There was no significant difference between SLPI and elafin serum levels in the disease groups. SLPI and elafin levels in AxSpA and nr-AxSpA groups were significantly higher compared to the control group (p<0.05). Based on receiver operating characteristic analysis, the diagnostic values of both parameters were found to be significant in the Ax-SpA and nr-AxSpA groups (p<0.05). There was no significant correlation between serum levels of SLPI and elafin and disease activity parameters. Significant positive correlations were found between SLPI and elafin in both the nr-AxSpA (p<0.05, r=0.870) and r-AxSpA (p<0.05, r=0.725) groups.

Conclusion

The levels of SLPI and elafin were found to be significantly elevated in patients with AxSpA, particularly in those with nr-AxSpA, compared to the control group. Therefore, SLPI and elafin can be used as therapeutic biomarkers for the diagnosis of AxSpA and nr-AxSpA. However, no relationship was found with disease activity.

No genetic causal association between periodontitis and ankylosing spondylitis: a bidirectional two-sample mendelian randomization analysis

BACKGROUND

Observational studies that reveal an association between periodontitis (PD) and ankylosing spondylitis (AS) exist. However, observational research is prone to reverse causality and confounding factors, which make it challenging to infer cause-and-effect relationships. We conducted a two-sample Mendelian randomization (MR) study to examine the causal relationship between the genetic prediction of PD and AS.

METHODS

In our study, single-nucleotide polymorphisms (SNPs) were defined as instrumental variables (IVs). The genetic association with PD came from the Gene-Lifestyle Interactions and Dental Endpoints (GLIDE) consortium, wherein 17353 cases of European ancestry and 28210 controls of European ancestry were included in this study. The genetic association with AS from the Neale Laboratory Consortium included 337,159 individuals from the United Kingdom, with 968 cases and 336,191 controls. MR analysis was mainly performed using the inverse-variance weighted (IVW) method. In addition, the robustness of the study findings was assessed using sensitivity, pleiotropy, and heterogeneity analyses.

RESULTS

Eighteen independent SNPs with P-values significantly smaller than 1 × 10- 5 were used as IV SNPs for PD, while 39 independent SNPs with P-values significantly smaller than 1 × 10- 5 were used as IV SNPs for AS. The results of the IVW method revealed no causal association between PD and AS (odds ratio = 1.00, 95% confidence interval: 0.99953 to 1.00067, P = 0.72). The MR-Egger method did not support the causal association between PD and AS. It is unlikely that horizontal pleiotropy distorts causal estimates based on sensitivity analysis. No significant heterogeneity was observed in the Q test. The ''leave-one-out'' analysis demonstrated that the robustness of our results was unaffected by eliminating any of the IVs. Likewise, no significant causative effect for AS on PD was observed in the inverse MR analysis.

CONCLUSIONS

The study results do not support shared heritability or a causal association between PD and AS.

Multimorbidity phenotypes in ankylosing spondylitis and their association with disease activity and functional impairment: Data from the prospective study of outcomes in ankylosing spondylitis cohort

OBJECTIVES

To examine the association of multimorbidity phenotypes at baseline with disease activity and functional status over time in ankylosing spondylitis (AS).

METHODS

Patient-reported AS morbidities (comorbidities, N = 28 and extra-musculoskeletal manifestations, EMMs, N = 3) within 3 years of enrollment with a prevalence ≥1 %, were included from the Prospective Study of Outcomes in Ankylosing Spondylitis (PSOAS) cohort. We defined multimorbidity as ≥2 morbidities (MM2+) and substantial multimorbidity as ≥5 morbidities (MM5+). Multimorbidity clusters or phenotypes were identified using K-median clustering. Disease activity (ASDAS-CRP) and functional status (BASFI) measures were collected every 6 months. Generalized estimating equation method was used to examine the associations of multimorbidity counts and multimorbidity clusters with measures of disease activity and functional status over time.

RESULTS

Among 1,270 AS patients (9,885 visits) with a median follow-up of 2.9 years (IQ range: 1.0-6.8 years), the prevalence of MM2+ and MM5+ was 49 % and 9 % respectively. We identified five multimorbidity clusters: depression (n = 321, 25 %), hypertension (n = 284, 22 %), uveitis (n = 274, 22 %), no morbidities (n = 238, 19 %), and miscellaneous (n = 153, 12 %). Patients in the depression cluster were more likely to be female and had significantly more morbidities and worse disease activity and functional status compared to those with no morbidities.

CONCLUSION

Approximately 49 % of AS patients in the PSOAS cohort had multimorbidity and five distinct multimorbidity phenotypes were identified. In addition to the number of morbidities, the type of morbidity appears to be important to longitudinal outcomes in AS. The depression cluster was associated with worse disease activity and function.

Body Mass Index Profile of Adult Patients with Inflammatory Bowel Disease in a Multicenter Study in Northeastern Brazil

Purpose

Inflammatory bowel disease (IBD) is a disease of increasing prevalence in developing countries. Obesity has emerged as a potential risk for IBD; however, the data in the literature are conflicting, and relevant studies in Brazil are limited. Here, we report body mass index profile (BMI) of patients with IBD treated at reference centers in three states of northeastern Brazil.

Patients and Methods

Observational descriptive study conducted from January 2021 through December 2021 in patient with IBD.

Results

Of 470 patients with IBD, 194 (41%) were classified as normal weight, 42 (9%) as underweight, 155 (33%) as overweight, and 79 (17%) as obese; CD patients were significantly more likely to be underweight than UC patients (p=0.031)Overweight patients were older (median age: 47 years) than normal-weight and underweight patients at diagnosis (38.5 and 35.5 years, respectively [p<0.0001]). IBD onset and diagnosis among overweight and obese individuals were associated with older age. More extensive disease behavior patterns predominated in UC, while forms associated with complications were prevalent in CD, irrespective of nutritional status. There was a higher frequency of compatible symptoms with axial joint inflammation among obese patients (p=0.005) and a lower frequency of compatible symptoms with peripheral joint inflammation in underweight patients (p=0.044) than in patients of normal weight. No significant difference in the frequency of different drug or surgical treatments was observed among the groups.

Conclusion

Despite the predominance of overweight and obesity in patients with IBD, no differences in the patterns of disease were seen between the overweight and normal-weight groups; however, obesity was associated with IBD onset in older adults and a higher frequency compatible symptom with axial joint inflammation. These data reinforce the importance of monitoring the nutritional status of IBD patients and the need for a multidisciplinary approach, as recommended in the current guidelines.

Management of Specific Clinical Profiles in Axial Spondyloarthritis: An Expert's Document Based on a Systematic Literature Review and Extended Delphi Process

INTRODUCTION

The management of specific clinical scenarios is not adequately addressed in national and international guidelines for axial spondyloarthritis (axSpA). Expert opinions could serve as a valuable complement to these documents.

METHODS

Seven expert rheumatologists identified controversial areas or gaps of current recommendations for the management of patients with axSpA. A systematic literature review (SLR) was performed to analyze the efficacy and safety of non-steroidal anti-inflammatory drugs (NSAIDs), corticosteroids, conventional synthetic, biologic and targeted synthetic disease-modifying antirheumatic drugs (csDMARDs, b/tsDMARDs) in axSpA regarding controversial areas or gaps. In a nominal group meeting, the results of the SLR were discussed and a set of statements were proposed. A Delphi process inviting 150 rheumatologists was followed to define the final statements. Agreement was defined as if at least 70% of the participants voted ≥ 7 (from 1, totally disagree, to 10, totally agree).

RESULTS

Three overarching principles and 17 recommendations were generated. All reached agreement. According to them, axSpA care should be holistic and individualized, taking into account objective findings, comorbidities, and patients' opinions and preferences. Integrating imaging and clinical assessment with biomarker analysis could also help in decision-making. Connected to treatments, in refractory enthesitis, b/tsDMARDs are recommended. If active peripheral arthritis, csDMARD might be considered before b/tsDMARDs. The presence of significant structural damage, long disease duration, or HLA-B27-negative status do not contraindicate for the use of b/tsDMARDs.

CONCLUSIONS

These recommendations are intended to complement guidelines by helping health professionals address and manage specific groups of patients, particular clinical scenarios, and gaps in axSpA.

The association between comorbidities and disease activity in spondyloarthritis - A narrative review

Comorbidities, including cardiovascular disease, osteoporosis, and depression, are more prevalent in patients with spondyloarthritis (SpA) than in the general population. Clinical and laboratory markers of disease activity are associated with numerous of these comorbidities, and studies suggest that the treatment of SpA can have a positive impact on comorbidities; conversely, managing comorbidities can improve disease activity. Therefore, the screening of comorbidities is considered a core component of a rheumatology consultation, and treatment should be performed in liaison with other health professionals (e.g. general physicians). Validated tools and questionnaires can be used for not only the detection but also the monitoring of potential comorbidities. Understanding whether a comorbidity is a separate disease entity, linked to SpA or its treatment, or an extra-musculoskeletal manifestation of the disease is important to identify the most appropriate treatment options.

Interleukin-17-targeted treatment in patients with spondyloarthritis and associated cardiometabolic risk profile

Spondyloarthritis is a group of immune-mediated rheumatic disorders that significantly impact patients' physical function and quality of life. Patients with spondyloarthritis experience a greater prevalence of cardiometabolic disorders, such as obesity, hypertension, dyslipidemia and diabetes mellitus, and these comorbidities are associated with increased spondyloarthritis disease activity and risk of cardiovascular events. This narrative review summarizes the evidence for a physiological link between inflammatory status and cardiometabolic comorbidities in spondyloarthritis, as well as the impact of interleukin (IL)-17 blockade versus other molecular mechanisms in patients with cardiometabolic conditions. The IL-23/IL-17 axis plays a pivotal role in the pathophysiology of spondyloarthritis by promoting inflammation and tissue remodeling at the affected joints and entheses. The importance of the IL-23/IL-17 signaling cascade in underlying sub-clinical inflammation in common cardiometabolic disorders suggests the existence of shared pathways between these processes and spondyloarthritis pathophysiology. Thus, a bidirectional relationship exists between the effects of biologic drugs and patients' cardiometabolic profile, which must be considered during treatment decision making. Biologic therapy may induce changes in patients' cardiometabolic status and cardiometabolic conditions may conversely impact the clinical response to biologic therapy. Available evidence regarding the impact of IL-17 blockade with secukinumab on cardiometabolic parameters suggests this drug does not interfere with traditional cardiovascular risk markers and could be associated with a decreased risk of cardiovascular events. Additionally, the efficacy and retention rates of secukinumab do not appear to be negatively affected by obesity, with some studies reporting a positive impact on clinical outcomes, contrary to that described with other approaches, such as tumor necrosis factor blockade. In this article, we also review evidence for this bidirectional association with other treatments for spondyloarthritis. Current evidence suggests that IL-17-targeted therapy with secukinumab is highly effective in spondyloarthritis patients with cardiometabolic comorbidities and may provide additional cardiometabolic benefits.

Association of anxiety, depression and resilience with overall health and functioning in axial spondyloarthritis (axSpA): a cross-sectional study

OBJECTIVES

To evaluate the association between anxiety, depression and resilience with overall health and functioning in axial spondyloarthritis (axSpA).

DESIGN

Cross-sectional evaluation of baseline data from a prospective cohort study, with recruitment from January 2018 to March 2021.

SETTING

Outpatient clinic in a tertiary hospital in Singapore.

PARTICIPANTS

Patients aged 21 years and above who were diagnosed with axSpA.

OUTCOME MEASURES

The Hospital Anxiety and Depression Scale (HADS) was used for assessing anxiety and depression, 10-item Connor Davidson Resilience Scale (CD-RISC-10) for resilience, Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) for disease activity, Bath Ankylosing Spondylitis Functional Index (BASFI) for functional limitation and Assessment of SpondyloArthritis International Society Health Index (ASAS HI) for overall health and functioning. Univariable and multivariable linear regression analyses were performed to assess the association between anxiety, depression and resilience with health and functioning.

RESULTS

We included 296 patients in this study. The median (IQR) score for HADS-Anxiety was 5.0 (2.0-8.0), with 13.5% and 13.9% having borderline abnormal and abnormal anxiety, respectively. The median (IQR) score for HADS-Depression was 3.0 (1.0-7.0), with 12.8% and 8.4% having borderline abnormal and abnormal depression, respectively. The median (IQR) CD-RISC-10 score was 29.0 (23.0-32.0) while the median (IQR) ASAS HI score was 4.0 (2.0-7.0). Apart from BASDAI, BASFI and disease duration, anxiety and depression were associated with overall health and functioning (β: 0.12, 95% CI 0.03, 0.20; β: 0.20, 95% CI 0.09, 0.31) in the multivariable linear regression. Level of resilience was not associated with health and functioning.

CONCLUSION

Anxiety and depression, but not resilience, were associated with poorer health and functioning. Clinicians could consider routinely screening for anxiety and depression in their patients, especially in patients with more severe symptoms.

Effect of body mass index on treatment response of biologic-/targeted synthetic-DMARDs in patients with rheumatoid arthritis, psoriatic arthritis and axial spondyloarthritis. A systematic review

BACKGROUND

Overweight and/or obese patients with inflammatory arthritis (IA) have higher disease activity and lower chances of achieving and/or maintaining the treatment targets. Weight/obesity also appears to negatively affect the response to tumor necrosis factor (TNF) inhibitors in patients with IA, including rheumatoid arthritis -RA, psoriatic arthritis -PsA, axial spondyloarthritis -AxSpA. We conducted a systematic literature review (SLR) for the effect of weight/body-mass-index (BMI) in the efficacy of all approved b- and targeted-synthetic (ts)- DMARDs for the treatment of IA.

METHODS

For this PROSPERO-registered SLR, we searched PubMed, Scopus and Cohrane-Library from inception up to June 21st 2022. Clinical-trials (randomized and non-randomized) and observational studies of RA, PsA or AxSpA patients that reported the effect of weight/BMI on response (all possible outcomes) to b/ts-DMARDs were included. Risk-of-bias was assessed via RoB2-Cochrane-tool and Newcastle-Ottawa-scale for randomized and non-randomized studies, respectively.

FINDINGS

Out of 996 references, 75 eventually fulfilled the inclusion criteria (of which 10 studies were retrieved through manual-search). Among the included studies (TNF-inhibitors: 34, IL-12/23 inhibitors: 4, IL-23 inhibitor: 1, IL-17 inhibitors: 7, tocilizumab: 18, abatacept: 8, rituximab: 3, JAK-inhibitors: 5), most had medium RoB. Efficacy of TNF-inhibitors was affected by BMI in all forms of IA. Data are not robust to compare the effect among various TNF-inhibitors. In contrast, favorable results of IL-23 and IL-17 inhibitors did not appear to be influenced by increased BMI in PsA or AxSpA patients. Similar evidence exists for tocilizumab (in RA) and for abatacept (in RA and PsA), while no conclusion can be drawn for rituximab. More data are needed for JAK-inhibitors, although the effect of weight/BMI does not seem to be significant so far.

INTERPRETATION

Weight/BMI should be considered in the treatment-plan of patients with IA, with its effect being more pronounced for TNF-inhibitors compared to other b/ts-DMARDs.

Central Obesity in Axial Spondyloarthritis: The Missing Link to Understanding Worse Outcomes in Women?

OBJECTIVE

To determine (1) the prevalence of central obesity in axial spondyloarthritis (axSpA) and its effect on disease-related outcomes and (2) how this differs between sexes.

METHODS

Data were extracted from the Ankylosing Spondylitis Registry of Ireland. Patients with physical measurements for the calculation of anthropometric measures were included. BMI and waist-to-hip ratio (WHR) were used to compare classifications of obesity. Comparison analyses based on sex and central obesity were carried out. Multivariate analysis examined the effects of these factors on the following patient-reported outcomes: the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), the Bath Ankylosing Spondylitis Functional Index (BASFI), the Ankylosing Spondylitis Quality of Life (ASQoL) questionnaire, and the Health Assessment Questionnaire (HAQ).

RESULTS

In total, 753 patients were included in the analysis. Of these patients, 29.6% (n = 223) were classified as obese based on their BMI, and 41.3% (n = 311) were classified as centrally obese according to the WHR. The prevalence of central obesity was significantly higher among women with axSpA compared to men (71.6% vs 29.9%, P < 0.01). Central obesity had a clear effect on patient outcomes, regardless of sex. Presence of central obesity was associated with significantly worse BASFI scores (P < 0.01), HAQ scores (P < 0.01), and ASQoL questionnaire scores (P = 0.01), with a nonsignificant trend toward worse BASDAI scores (P = 0.07).

CONCLUSION

There was a high prevalence of central obesity as assessed by the WHR in axSpA, most notably among women with axSpA. This modifiable comorbidity was significantly associated with worse quality of life, greater impairment of functional ability, and a trend toward worse disease activity. Regular use of the WHR to screen for central obesity as part of an axSpA assessment would provide an opportunity for prompt identification and intervention for at-risk patients.

Increased proportions of inflammatory T cells and their correlations with cytokines and clinical parameters in patients with ankylosing spondylitis from northern Sweden

Ankylosing spondylitis (AS) is an autoimmune disease affecting parts of the skeletal structure in particular. Previously increased levels of the inflammatory cell types Th17, Th22, Tc17 and Tc22 cells have been shown to be associated with AS. Here, we analysed the levels of inflammatory T cell subsets, related cytokines and clinical characteristics of AS patients vs controls from northern Sweden. Peripheral blood mononuclear cells (PBMCs) obtained from 50 AS patients and 50 matched controls were short term stimulated with PMA/Ionomycin, stained and analysed by flow cytometry. Plasma levels of Interleukin (IL)‐17, IL‐22, IL‐10 as well as clinically relevant markers were determined. Compared to male controls, male AS patients showed 1.5‐ to 2‐fold increases of Th17 (P = .013), Th22 (P = .003) and Tc22 (P = .024) among CD45⁺CD3⁺ lymphocytes. Plasma IL‐22 levels correlated with the Tc17 proportion in male patients (R_s = 0.499, P = .003) and plasma IL‐10 levels were inversely correlated with Tc17 among all patients (R_s = −0.276, P = .05). Male patients with syndesmophytes showed significantly higher Th17 proportions (P = .038). In female AS patients, Tc22 was negatively correlated with C‐reactive protein (high sensitivity) (hsCRP) (R_s = −0.573, P = .016). We confirmed increased proportions of inflammatory T cells and correlations with relevant cytokines from male AS patients. The correlation between Th17 and syndesmophytes supports a role of Th17 in the pathogenic process.

Treatment Failure in Axial Spondyloarthritis: Insights for a Standardized Definition

Axial spondyloarthritis is a chronic inflammatory rheumatic disease that affects the axial skeleton and causes severe pain and disability. It may be also associated with extra-articular manifestations. Early diagnosis and appropriate treatment can reduce the severity of the disease and the risk of progression. The biological disease-modifying antirheumatic drugs (bDMARDs) tumor necrosis factor alpha (TNFα) inhibitors (TNFi) and the anti-interleukin (IL)-17A antibodies secukinumab and ixekizumab are effective agents to reduce disease activity and minimize the inflammation that damages the joints. New alternatives such as Janus kinase (JAK) inhibitors are also available. Unfortunately, response rates to bDMARDs are far from optimal, and many patients experience so-called treatment failure. The definition of treatment failure definition is often vague and may depend on the rigorousness of the therapeutic goal, the inclusion or not of peripheral symptoms/extra-articular manifestations, or patients' overall health. After an exhaustive bibliographic review, we propose a definition based on loss of the following status: low disease activity assessed by Ankylosing Spondylitis Disease Activity Score (ASDAS)-CRP, absence of extra-articular manifestations, and low disease impact on the patients' general health. Apart from discontinuing the therapy because of safety or intolerance reasons, two types of treatment failure can be differentiated depending on when it occurs: primary failure (no response within 6 months after treatment initiation, or lack of efficacy) and secondary failure (response within 6 months but lost thereafter, or loss of efficacy over time). Physicians should carefully consider the moment and the reason for the treatment failure to decide the next therapeutic step. In the case of primary failure on a first TNFi, it seems reasonable to switch to another class of drugs, i.e., an anti-IL-17 agent, as phase III trials showed that the response to IL-17 blockade was higher than to placebo in patients previously exposed to TNFi. When secondary failure occurs, and loss of efficacy is suspected to be caused by antidrug antibodies (ADAs), it is advisable to analyze serum TNFi and ADAs concentrations, if possible; in the presence of ADAs and low TNFi levels, changing the TNFi is rational as it may restore the TNFα blocking capacity. If ADAs are absent/low with adequate drug therapeutic levels, switching to another target might be the best strategy.

Lifestyle modification and inflammation in people with axial spondyloarthropathy-A scoping review

INTRODUCTION

People with axial spondyloarthritis (AS) have an inflammatory profile, increasing the risk of hypertension, type 2 diabetes, obesity, and dyslipidaemia. Consequently, AS is linked with co-morbidities such as cardiovascular disease (CVD). Physical inactivity, diet, smoking, alcohol consumption, and obesity influence inflammation, but knowledge of the interaction between these with inflammation, disease activity, and CVD risk in AS is dominated by cross-sectional research.

METHODS

A review of the literature was conducted between July 2020 and December 2021. The focus of the scoping review is to summarise longitudinal and randomised control trials in humans to investigate how tracking or modifying lifestyle influences inflammation and disease burden in patients with AS. KEY MESSAGES: (1) Lifestyle modifications, especially increased physical activity (PA), exercise, and smoking cessation, are critical in managing AS. (2) Smoking is negatively associated with patient reported outcome measures with AS, plus pharmaceutical treatment adherence, but links with structural radiographic progression are inconclusive. (3) Paucity of data warrant structured studies measuring inflammatory cytokine responses to lifestyle modification in AS.

CONCLUSION

Increased PA, exercise, and smoking cessation should be supported at every given opportunity to improve health outcomes in patients with AS. The link between smoking and radiographic progression needs further investigation. Studies investigating the longitudinal effect of body weight, alcohol, and psychosocial factors on disease activity and physical function in patients with AS are needed. Given the link between inflammation and AS, future studies should also incorporate markers of chronic inflammation beyond the standard C-reactive protein and erythrocyte sedimentation rate measurements.

2022 French Society for Rheumatology (SFR) recommendations on the everyday management of patients with spondyloarthritis, including psoriatic arthritis

OBJECTIVE

Update the French Society for Rheumatology (SFR) recommendations on the everyday management of patients with spondyloarthritis, including psoriatic arthritis.

METHODS

Following standardized procedures, a systematic literature review was done by four supervised rheumatology residents based on questions defined by a task force of 16 attending rheumatologists. The findings were reviewed during three working meetings that culminated in each recommendation receiving a grade and the level of agreement among experts being determined.

RESULTS

Five general principles and 15 recommendations were developed. They take into account pharmacological and non-pharmacological measures along with treatment methods based on the dominant phenotype present (axial, articular, enthesitis/dactylitis) and the extra-articular manifestations (psoriasis, inflammatory bowel disease, uveitis). NSAIDs are the first-line pharmacological treatment in the various presentations. Conventional synthetic disease modifying antirheumatic drugs (csDMARDs) are not indicated in the axial and isolated entheseal forms. If the response to conventional treatment is not adequate, targeted therapies (biologics, synthetics) should be considered; the indications depend on the clinical phenotype and presence of extra-articular manifestations.

CONCLUSION

This update incorporates recent data (published since the prior update in 2018) and the predominant clinical phenotype concept. It aims to help physicians with the everyday management of patients affected by spondyloarthritis, including psoriatic arthritis.

Depression and anxiety symptoms at TNF inhibitor initiation are associated with impaired treatment response in axial spondyloarthritis

OBJECTIVES

Depression and anxiety are associated with more severe disease in cross-sectional studies of axial spondyloarthritis (axSpA). We examined the association between baseline symptoms of depression or anxiety and response to TNF inhibitors (TNFi) in axSpA.

METHODS

Biologic naïve participants from a national axSpA register completed the Hospital Anxiety and Depression Scale (HADS) before initiating TNFi. Symptoms of anxiety and depression were each categorized as moderate-severe (≥11), mild (8-10) and 'none' (≤7), and compared against change in disease indices [BASDAI and AS Disease Activity Score (ASDAS)] over time and time to treatment discontinuation using marginal structural models. Inverse-probability weights balanced baseline age, gender, BMI, deprivation, education and baseline values of respective disease indices.

RESULTS

Of the 742 participants (67% male, mean age 45 years), 176 (24%) had moderate-severe and 26% mild depression; 295 (40%) had moderate-severe and 23% mild anxiety. Baseline disease activity was higher in higher HADS symptom categories for both depression and anxiety. Participants with moderate-severe depression had significantly poorer response compared with those with 'none' throughout follow-up. At 6 months, the difference was approximately 2.2 BASDAI and 0.8 ASDAS units after balancing their baseline values. Equivalent comparisons for anxiety were 1.7 BASDAI and 0.7 ASDAS units. Treatment discontinuation was 1.59-fold higher (hazard ratio 95% CI: 1.12, 2.26) in participants with moderate-severe anxiety compared with 'none'.

CONCLUSIONS

Symptoms of depression and anxiety at TNFi initiation are associated with poorer treatment outcomes. Targeted interventions to optimize mental health have potential to substantially improve treatment response and persistence.

Lifestyle Factors and Disease Activity over Time in Early Axial Spondyloarthritis - The SPondyloArthritis Caught Early (SPACE) Cohort

OBJECTIVE

Our aim was to study the importance of baseline Body Mass Index (BMI), smoking and alcohol consumption (AC) for disease activity (DA) over one year in early axial spondyloarthritis (axSpA), stratified by sex.

METHODS

In the SPondyloArthritis Caught Early cohort (patients with chronic back pain for ≥3 months, ≤2 years and onset <45 years), ASDAS was recorded at inclusion, 3 and 12 months. All patients included in the analysis had axSpA based on a high physician's level of confidence at baseline. Differences in ASDAS over 1 year by BMI (normal <25, overweight 25-29.9, obese ≥30 kg/m²), smoking history (never/previous/current) and AC (none, 0.1-2, 3-5, ≥6 units/week) at baseline were estimated using mixed linear regression models.

RESULTS

There were 344 subjects (mean age 30 years; 49% men). In women, obesity was associated with 0.60 (95% CL 0.28, 0.91) higher ASDAS compared to normal BMI. In both sexes, AC tended to be associated with lower DA over one year, with a significant association only in women with the highest AC (mean difference -0.55 (96% CL-1.05, -0.04). Smoking was associated with higher ASDAS over one year compared to never smoking in both sexes, albeit the difference reached statistical significance only in female former smokers. Results were similar in multivariable analysis, adjusted for all lifestyle factors and other confounders.

CONCLUSION

In early axSpA, BMI and smoking are associated with higher DA over one year, and AC with lower DA. The magnitude of the modest associations may differ between men and women.

The relationship between body mass index, disease activity, and exercise in ankylosing spondylitis

BACKGROUND

Ankylosing spondylitis (AS) is associated with elevated cardiovascular (CV) risk and obesity is a common, modifiable risk factor. Our aims were 1) to assess the relationship of BMI with disease activity in AS patients, and 2) to assess the extent to which the effect is mediated through exercise.

METHODS

We used data from a prospective AS cohort with a median follow-up of 7 years. To determine the association of BMI (kg/m² ) with disease activity as measured by the Ankylosing Spondylitis Disease Activity Score (ASDAS), we used generalized estimating equations with inverse probability weighting to account for repeated measures per subject and time-varying confounding. To estimate the direct effect of overweight/obese BMI on disease activity, and the indirect effect through exercise, we performed a mediation analysis.

RESULTS

There were 183 subjects with available BMI and disease activity data (77% male, 70% white, mean age 40.8 ± 13.3 years). Higher BMI was significantly associated with higher disease activity over time; on average, for a 1 kg/m² higher BMI, the ASDAS was 0.06 units higher (95% CI 0.04 - 0.08) after adjustment for important confounders. The direct effect of an overweight/obese BMI accounted for most of the total effect on disease activity, with a smaller indirect effect mediated by exercise (7%).

CONCLUSION

Higher BMI was associated with higher disease activity in a prospective AS cohort. We found that being overweight/obese largely influenced disease activity directly, rather than indirectly through exercise. Other mechanisms such as increased inflammation may better explain the obesity-disease activity association.