Discovertebral (Andersson) lesions in severe ankylosing spondylitis: a study using MRI and conventional radiography

The objective of this study is to investigate the prevalence of Andersson lesions (AL) in ankylosing spondylitis (AS) patients who will start anti-tumor necrosis factor (TNF) treatment. Radiographs and magnetic resonance imaging (MRI) of the spine were performed before therapy with anti-TNF. ALs were defined as discovertebral endplate destructions on MRI, associated with bone marrow edema and fat replacement or sclerosis, a decreased signal on T1, enhancement after contrast administration (gadolinium diethylenetriamine pentaacetic acid (Gd-DTPA)), and increased signal on T2 and short tau inversion recovery (STIR). Additionally, conventional radiography showed a fracture line, irregular endplates, and increased sclerosis of adjacent vertebral bodies. Fifty-six AS patients were included, 68% males, mean age of 43 years, and mean disease duration of 11 years. The mean bath ankylosing spondylitis disease activity index was 6.4, and 24% of all patients had ankylosis. Only one patient showed a discovertebral abnormality with bone marrow edema of more than 50% of the vertebral bodies adjacent to the intervertebral disk of T7/T8 and T9/T10, a hypodense signal area on T1, and a high signal on STIR. Irregular endplates were depicted, and T1 after Gd-DTPA demonstrated high signal intensity around the disk margins. However, no fracture line was visible on conventional radiology, and therefore, this case was not considered to be an AL. No AL was detected in our AS patients, who were candidates for anti-TNF treatment. One patient showed a discovertebral abnormality on MRI, without a fracture line on conventional radiology. The relative small proportion of patients with a long-established disease might explain this finding for, particularly, an ankylosed spine is prone to develop an AL

What do we miss? ASAS non-responders on anti-TNF therapy show improvement in performance-based physical function

Objective: A prospective study was conducted in order to establish whether AS patients, who are defined as non-responders after 3 months of anti-TNF therapy, show improvement on performance-based tests of physical functioning. Methods: At baseline and 3 months after the start of anti-TNF therapy, AS patients completed seven performance-based tests of physical functioning, questionnaires on self-reported physical functioning (BASFI) and disease activity (BASDAI), and a pain and a global patient assessment. The concordance between ≥20% intra-individual improvement on the performance-based test of physical functioning and (i) response to anti-TNF therapy [Assessment of SpondyloArthritis International Society 20% (ASAS20) response] and (ii) ≥20% intra-individual improvement on self-reported physical functioning (BASFI) was assessed. Results: One hundred AS patients were included, of which 82 patients completed all tests at both time points. After 3 months of anti-TNF therapy, 27 (32.9%) patients were categorized as non-responders according to the ASAS20 response criteria. Improvement in performance-based physical functioning was seen in 13 of the 27 non-responders (48.1%) (i.e. n = 13/82 = 15.9% of the total group). Furthermore, 30 (36.6%) patients showed no improvement on self-reported physical functioning (BASFI). However, 17 of the 30 (56.7%) patients did improve on the performance-based tests of physical functioning (i.e. n = 17/82 = 20.7% of the total group).Conclusion: After 3 months of anti-TNF therapy, performance-based tests of physical functioning showed improvement in 48.1% of the ASAS20 non-responders. With these performance-based tests, new information on outcome after anti-TNF therapy can be generated. Using performance-based tests alongside the BASFI could have additional value in the evaluation of outcomes for patients receiving anti-TNF therapy

Fat mass lowers the response to tumor necrosis factor-a blockers in patients with ankylosing spondylitis

Objective. Our main objective was to assess the relationship between body composition (BC) and response to tumor necrosis factor-a (TNF-a) blocker treatment in patients with ankylosing spondylitis (AS). Our secondary objective was to evaluate the change of BC after treatment, accounting for sex and age. Methods. All included patients fulfilled the modified New York criteria for AS and were naive to TNF-a blocker. They were followed for at least 6 months after the start of etanercept or adalimumab. The Ankylosing Spondylitis Disease Activity Score containing C-reactive protein (ASDAS-CRP) and the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) were reported. BC was assessed by whole body dual-energy X-ray absorptiometry. Body fat percentage (BF%), fat mass index (FMI), and fat free mass index (FFMI) were reported as absolute values and as percentiles. Results. Forty-one patients were included (61% men). The median followup was 14.3 months (interquartile range 8.4-19.4). After multivariate regression analysis, more fat at baseline (BF%, FMI, or FMI percentile) was significantly related with a lower chance of achieving a clinically important improvement of the ASDAS-CRP or BASDAI after treatment. The body composition did not change significantly after treatment, but there was a trend toward muscle recovery in men (FFMI change from 34.0th to 37.4th percentile). Conclusion. Higher body fat content at baseline was independently associated with a worse response to treatment with TNF-a blockers, measured by ASDAS-CRP and BASDAI change, and might contribute to the lower response rates in female patients. Also, there is a trend toward muscle mass recovery in male patients after treatment

Prevalence and Radiographic Progression of Hip Involvement in Patients With Ankylosing Spondylitis Treated With Tumor Necrosis Factor Inhibitors

OBJECTIVE: To examine the prevalence of hip involvement between sexes in patients with ankylosing spondylitis (AS) treated with tumor necrosis factor inhibitors (TNFi) and to estimate the effect of TNFi on radiographic progression of hip involvement compared to the spine. METHODS: Two hundred ninety-nine patients with AS treated with TNFi (215 men; median age: 43 yrs [IQR 36-52], median disease duration: 7.6 yrs [IQR 2-15]) were evaluated for hip involvement, defined radiographically as Bath AS Radiological Hip Index (BASRI-hip) score ≥ 2. Those who received TNFi for ≥ 2 years (263/299) were assessed for radiographic progression. Radiographs of the pelvis and spine, obtained at baseline (ie, before TNFi initiation), were compared retrospectively to those obtained after 2.5 (SD 0.7) years and 7.0 (SD 2.3) years of TNFi treatment. Both hips were scored by BASRI-hip score and mean joint space width (MJSW). Spinal radiographs were scored by modified Stoke AS Spinal Score (mSASSS). RESULTS: The prevalence of hip involvement at baseline was 113/299 (38%) patients, of whom 87/215 (41%) were male and 26/84 (31%) were female (P = 0.10). In both sexes with hip involvement at baseline, BASRI-hip score and MJSW did not change significantly during follow-up. In males and females without baseline hip involvement, the BASRI-hip score remained unchanged after 2.5 (SD 0.7) years but increased significantly after 7.0 (SD 2.3) years, without reaching the cut-off of 2. In contrast, the MJSW slightly decreased at the 2 follow-up timepoints (ie, after 2.5 and 7.0 yrs). The mSASSS increased significantly during the follow-up in both sexes, regardless of hip involvement. CONCLUSION: In our study, approximately one-third of patients with AS had hip involvement, which seemed to stabilize with TNFi treatment. No sex differences in the prevalence or progression of this manifestation were found