The relationship between disease-related characteristics and conduction disturbances in ankylosing spondylitis.

OBJECTIVES: Ankylosing spondylitis (AS) is associated with an increased cardiovascular (CV) risk. Conduction disturbances (CD) may explain the CV burden, as they are independently associated with cardiac disease. The aim of this study was (i) to determine the prevalence of CD in AS, and (ii) to evaluate the relationship between CD and demographic and AS-related characteristics. METHODS: A rheumatological evaluation assessing demographic and AS-related characteristics and a resting standard 12-lead electrocardiogram (ECG) were performed in 131 consecutive AS patients. RESULTS: A first-degree atrioventricular (AV) block was found in six (4.6%) patients. One (0.8%) patient suffered from a complete right bundle branch block (RBBB) and one (0.8%) patient had a left anterior hemiblock. A prolonged QRS (pQRS) interval was observed in 38 (29.2%) patients, including those with a complete or incomplete BBB. Age, disease duration, and body mass index (BMI) were significantly associated with the PR interval, and male gender, disease duration, and the Bath Ankylosing Spondylitis Metrology Index (BASMI) with the QRS interval. In multivariate analyses, disease duration remained independently associated with both the PR and the QRS intervals. CONCLUSION: Intraventricular CD is highly prevalent in AS, particularly in patients with long-standing disease. Further research is needed to determine whether intraventricular CD contribute to the increased CV risk and long-term CV mortality in AS.

Improvement of lipid profile is accompanied by atheroprotective alterations in high-density lipoprotein composition upon tumor necrosis factor blockade: a prospective cohort study in ankylosing spondylitis.

OBJECTIVE: Cardiovascular mortality is increased in ankylosing spondylitis (AS), and inflammation plays an important role. Inflammation deteriorates the lipid profile and alters high-density lipoprotein cholesterol (HDL-c) composition, reflected by increased concentrations of serum amyloid A (SAA) within the particle. Anti-tumor necrosis factor (anti-TNF) treatment may improve these parameters. We therefore undertook the present study to investigate the effects of etanercept on lipid profile and HDL composition in AS. METHODS: In 92 AS patients, lipid levels and their association with the inflammation markers C-reactive protein (CRP), erythrocyte sedimentation rate, and SAA were evaluated serially during 3 months of etanercept treatment. HDL composition and its relationship to inflammation markers was determined in a subgroup of patients, using surface-enhanced laser desorption/ionization time-of-flight analysis. RESULTS: With anti-TNF treatment, levels of all parameters of inflammation decreased significantly, whereas total cholesterol, HDL-c, and apolipoprotein A-I (Apo A-I) levels increased significantly. This resulted in a better total cholesterol:HDL-c ratio (from 3.9 to 3.7) (although the difference was not statistically significant), and an improved Apo B:Apo A-I ratio, which decreased by 7.5% over time (P=0.008). In general, increases in levels of all lipid parameters were associated with reductions in inflammatory activity. In addition, SAA was present at high levels within HDL particles from AS patients with increased CRP levels and disappeared during treatment, in parallel with declining plasma levels of SAA. CONCLUSION: Our results show for the first time that during anti-TNF therapy for AS, along with favorable changes in the lipid profile, HDL composition is actually altered whereby SAA disappears from the HDL particle, increasing its atheroprotective ability. These findings demonstrate the importance of understanding the role of functional characteristics of HDL-c in cardiovascular diseases related to chronic inflammatory conditions.

Immunogenicity does not influence treatment with etanercept in patients with ankylosing spondylitis.

BACKGROUND: Immunogenicity, specifically the onset of antibodies against tumour necrosis factor (TNF) blocking agents, seems to play an important role in non-response to treatment with these drugs. OBJECTIVES: To assess the relation of clinical response of ankylosing spondylitis (AS) to etanercept with etanercept levels, and the presence of antibodies to etanercept. METHODS: Patients with AS were treated with etanercept 25 mg twice weekly, according to the international Assessment in Ankylosing Spondylitis (ASAS) working group consensus statement. Sera were collected at baseline and after 3 and 6 months of treatment. Clinical response was defined as a 50% improvement or as an absolute improvement of 2 points on a (0-10 scale) Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) score. Functional etanercept levels were measured by a newly developed ELISA, measuring the binding of etanercept to TNF. Antibodies against etanercept were measured with a two-site assay and antigen binding test. Clinical data were used to correlate disease activity with serum etanercept levels. RESULTS: In all, 53 consecutive patients were included. After 3 months of treatment 40 patients (76%) fulfilled the response criteria. Mean etanercept levels were 2.7 mg/litre and 3.0 mg/litre after 3 and 6 months respectively. Characteristics and etanercept levels of responders and non-responders were similar. No antibodies to etanercept were detected with any of the assays. CONCLUSION: Etanercept levels of responders and non-responders were similar and no antibodies to etanercept were detected with any of the assays. This study indicates that etanercept is much less immunogenic compared with the other TNF-blocking agents.