Body mass index is related with the presence of syndesmophyte in axial spondyloarthritis: Data from the Korean College of Rheumatology BIOlogics (KOBIO) registry

<p><b>Objective:</b> We investigated whether body mass index (BMI) is associated with parameters of disease activity and clinical manifestations in axial spondyloarthritis (axSpA).</p> <p><b>Methods:</b> Demographic, clinical, and radiological features and disease activity indexes from 789 axSpA patients (619 males and 170 females) were obtained from the Korean College of Rheumatology BIOlogics (KOBIO) registry. BMI (kg/m²) was classified into normal (BMI <23.0), overweight (23.0 ≤ BMI <25.0), and obese (BMI ≥25.0). Disease activity indexes included Bath ankylosing spondylitis disease activity index (BASDAI), erythrocyte sediment rate (ESR), C-reactive protein (CRP), and ankylosing spondylitis disease activity score (ASDAS).</p> <p><b>Results:</b> The mean BMI in patients with axSpA was 23.3 ± 3.5. 50.2% of all patients were overweight or obese. Overweight/obese patients had more syndesmophyte and less peripheral arthritis than those in normal BMI patients (<i>p</i> < 0.001 and <i>p</i> < 0.030, respectively). BMI was not associated with disease activity indexes in axSpA patients. Patients with syndesmophyte had higher BMI than those without syndesmophyte (24.2 ± 3.6 vs. 22.9 ± 3.3, <i>p</i> < 0.001). Multivariate logistic regression analysis showed that increased BMI was closely related with the presence of syndesmophyte (OR = 1.086, 95% CI 1.031–1.143, <i>p</i> = 0.002)</p> <p><b>Conclusions:</b> Our results imply that increased BMI is significantly associated with the presence of syndesmophyte, but not with disease activity in axSpA.</p

Number of patients according to the course of treatment.

<p>TNF, tumor necrosis factor.</p><p>Number of patients according to the course of treatment.</p

Predictors of Switching Anti-Tumor Necrosis Factor Therapy in Patients with Ankylosing Spondylitis

<div><p>The aim of this study was to investigate the potential predictors of switching tumor necrosis factor (TNF)-α inhibitors in Korean patients with ankylosing spondylitis (AS). The patients who had been treated with TNF-α inhibitors were divided into two groups depending on whether they had switched TNF-α inhibitors. Demographic, clinical, laboratory, and treatment data at the time of initiation of TNF-α inhibitor treatment were compared between switchers and non-switchers, and within switchers according to the reasons for switching. Of the 269 patients, 70 (23%) had switched TNF-α inhibitors once; of these, 11 switched again. The median follow-up time was 52.7 months. Three- and five-year drug survival rates were 52%/48% for infliximab, 62%/42% for etanercept, and 71%/51% for adalimumab, respectively. Switchers were more likely to be prescribed disease-modifying anti-rheumatic drugs than non-switchers. A history of joint surgery and complete ankylosis of the sacroiliac joint was more frequent in switchers. Multivariate Cox’s proportional hazard analysis showed that the use of adalimumab as the first TNF-α inhibitor was less likely to lead to switching and complete ankylosis of the sacroiliac joints was more likely to lead to switching. The principal reasons for switching were drug inefficacy and adverse events, but the differences in the clinical data of these two groups of switchers were not significant. In AS patients who are candidates for TNF-α inhibitor therapy, switching may improve the therapeutic outcome based on clinical information.</p></div

Baseline characteristics and laboratory findings of patients starting their first TNF-α inhibitor according to whether they subsequently switched or not.

<p>TNF, tumor necrosis factor; BMI, body mass index; BASDAI, Bath Ankylosing Spondylitis Disease Activity Index; ESR, erythrocyte sedimentation rate; CRP, C-reactive protein; AST, aspartate aminotransferase; ALT, alanine aminotransferase; INH, isoniazid; NSAIDs, non-steroidal anti-inflammatory drugs; DMARDs, disease-modifying anti-rheumatic drugs. Continuous variables are shown as medians and interquartile range.</p><p>Baseline characteristics and laboratory findings of patients starting their first TNF-α inhibitor according to whether they subsequently switched or not.</p

Predictors of TNF-α inhibitor switching.

<p>ESR, erythrocyte sedimentation rate; CRP, C-reactive protein; DMARDs, disease-modifying anti-rheumatic drugs.</p><p>Predictors of TNF-α inhibitor switching.</p

Number of patients according to the course of treatment.

<p>TNF, tumor necrosis factor.</p><p>Number of patients according to the course of treatment.</p

Baseline characteristics of patients at the time of TNF-α inhibitor initiation according to the reason for subsequent switching.

<p>TNF, tumor necrosis factor; BMI, body mass index; BASDAI, Bath Ankylosing Spondylitis Disease Activity Index; ESR, erythrocyte sedimentation rate; CRP, C-reactive protein; AST, aspartate aminotransferase; ALT, alanine aminotransferase; INH, isoniazid; NSAIDs, non-steroidal anti-inflammatory drugs; DMARDs, disease-modifying anti-rheumatic drugs.</p><p>Continuous variables are shown as medians and interquartile range.</p><p>Baseline characteristics of patients at the time of TNF-α inhibitor initiation according to the reason for subsequent switching.</p

Coefficients from a linear regression model examining the association of grip strength (kg) with total and individual radiographic feature scores of hand and knee osteoarthritis.

<p>Coefficients from a linear regression model examining the association of grip strength (kg) with total and individual radiographic feature scores of hand and knee osteoarthritis.</p

Baseline characteristics and laboratory findings of patients starting their first TNF-α inhibitor according to whether they subsequently switched or not.

<p>TNF, tumor necrosis factor; BMI, body mass index; BASDAI, Bath Ankylosing Spondylitis Disease Activity Index; ESR, erythrocyte sedimentation rate; CRP, C-reactive protein; AST, aspartate aminotransferase; ALT, alanine aminotransferase; INH, isoniazid; NSAIDs, non-steroidal anti-inflammatory drugs; DMARDs, disease-modifying anti-rheumatic drugs. Continuous variables are shown as medians and interquartile range.</p><p>Baseline characteristics and laboratory findings of patients starting their first TNF-α inhibitor according to whether they subsequently switched or not.</p

Odds ratios from a logistic regression model examining the association of grip strength (5 kg) for with individual radiographic features of hand and knee osteoarthritis with a range of less than 10 points.

<p>Odds ratios from a logistic regression model examining the association of grip strength (5 kg) for with individual radiographic features of hand and knee osteoarthritis with a range of less than 10 points.</p