M J L Peters

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.

Signs of accelerated preclinical atherosclerosis in patients with ankylosing spondylitis.

Objective. Preliminary evidence suggests that ankylosing spondylitis (AS) is associated with an increased cardiovascular (CV) risk. We investigated subclinical atherosclerosis and arterial stiffness in patients with AS compared with controls, and identified CV and AS related risk factors for atherosclerotic disease. Methods. A total of 59 patients with AS who were scheduled for etanercept treatment according to the ASsessments in Ankylosing Spondylitis guidelines and 30 healthy controls were recruited. Subclinical atherosclerosis was assessed as the average intima-media thickness (IMT) of the common carotid artery. Arterial stiffness was determined by distensibility, compliance, and Young’s elastic modulus of the carotid artery. Results. AS patients had a greater IMT (0.62 ± 0.09 mm vs 0.57 ± 0.09 mm in controls; p = 0.02), a difference that remained after adjustment for traditional CV risk factors. AS was associated with higher carotid pulse pressure (47 ± 7 mm Hg vs 44 ± 8 mm Hg in controls; p = 0.04), but this was not due to local vessel wall properties. Among AS patients, age and body mass index (BMI) were determinants of IMT. Age, BMI, total cholesterol, triglycerides, and disease duration were identified as determinants of stiffness indices. No relationship was found between large-vessel properties and higher Bath AS disease indices or C-reactive protein values. Conclusion. AS was associated with subclinical atherosclerosis and arterial stiffness, supporting epidemiological evidence of an increased CV risk in these patients. Whether these differences are due to AS or to a higher prevalence of CV risk factors in patients with AS remains to be determined.

Microvascular function is impaired in ankylosing spondylitis and improves after tumour necrosis factor α blockade

Objectives: Ankylosing spondylitis (AS) is associated with increased cardiovascular morbidity and mortality. Microvascular function has been linked to several risk factors for cardiovascular disease. Inflammation in AS may cause microvascular dysfunction. To test this, we assessed microvascular function in (a) patients with AS compared to healthy controls and (b) patients with AS before and after 1 month of anti-tumour necrosis factor (TNF)α treatment with etanercept. Methods: A total of 15 consecutive patients with AS, who were scheduled for etanercept treatment according to the Assessment in Ankylosing Spondylitis (ASAS) group guidelines, and 12 healthy controls matched for age and sex, were recruited. Endothelium-dependent and independent vasodilatation in skin were evaluated with laser Doppler fluxmetry after iontophoresis of acetylcholine and sodium nitroprusside, respectively. Videomicroscopy was used to measure recruitment of skin capillaries after arterial occlusion. Results: Compared to healthy controls, patients with AS had impaired endothelium-dependent vasodilatation and capillary recruitment. Following anti-TNFα treatment, microvascular function improved significantly for endothelium-dependent vasodilatation (pu200a=u200a0.03) and capillary recruitment (pu200a=u200a0.006). A significant correlation was observed between changes in endothelium-dependent vasodilatation and changes in erythrocyte sedimentation rate (ESR) (ru200a=u200a−0.56; pu200a=u200a0.03). Conclusion: Microvascular dysfunction is present in patients with AS with active disease, but improves as inflammation regresses after TNFα blockade.

Increased disease activity is associated with a deteriorated lipid profile in patients with ankylosing spondylitis.

Background: Cardiovascular mortality is increased in patients with ankylosing spondylitis. A possible explanation might be a more prevalent atherogenic lipid profile in patients with ankylosing spondylitis than in the general population. It has been postulated that inflammation deteriorates the lipid profile, thereby increasing cardiovascular risk. Objective: To explore the association between disease activity and lipid profile in patients with ankylosing spondylitis. Methods: Disease activity parameters for ankylosing spondylitis and lipid levels (total cholesterol, high-density lipoprotein cholesterol (HDLc) and triglycerides) were measured in 45 patients with ankylosing spondylitis for 6 months after starting treatment with leflunomide or placebo. Findings in this treatment group were compared with those in 10 patients with ankylosing spondylitis treated with etanercept. A specialised regression model, adjusting for repeated measurements, age and sex, was used to assess the influence of the disease activity variables on the lipid levels. Results: Multilevel regression analyses showed significant associations between disease activity parameters and lipid levels—for instance, an increase of 30 mm at the end of the first hour in erythrocyte sedimentation rate was associated with a decrease of about 6% in total cholesterol level and a decrease of about 11% in HDLc levels. Similar significant associations were found between other disease activity parameters and lipid levels. Conclusion: Increase in disease activity was associated with decreases in lipid levels. The decrease in HDLc levels tended to be almost twice as large as the decrease in total cholesterol levels, resulting in a more atherogenic lipid profile. Hence, effective treatment of disease activity in patients with ankylosing spondylitis may lower the cardiovascular risk by improving the lipid profile.

The potential harm of oxygen therapy in medical emergencies

In medical emergencies, supplemental oxygen is often administrated routinely. Most paramedics and physicians believe that high concentrations of oxygen are life-saving [1]. Over the last century, however, a plethora of studies point to possible detrimental effects of hyperoxia induced by supplemental oxygen in a variety of medical emergencies. This viewpoint provides a historical overview and questions the safety of routine high-dose oxygen administration and is based on pathophysiology and (pre)clinical findings in various medical emergencies.

Cardiovascular disease prevalence in patients with inflammatory arthritis, diabetes mellitus and osteoarthritis: a cross-sectional study in primary care

BackgroundThere is accumulating evidence for an increased cardiovascular burden in inflammatory arthritis, but the true magnitude of this cardiovascular burden is still debated. We sought to determine the prevalence rate of non-fatal cardiovascular disease (CVD) in inflammatory arthritis, diabetes mellitus and osteoarthritis (non-systemic inflammatory comparator) compared to controls, in primary care.MethodsData on CVD morbidity (ICPC codes K75 (myocardial infarction), K89 (transient ischemic attack), and/or K90 (stroke/cerebrovascular accident)) from patients with inflammatory arthritis (n = 1,518), diabetes mellitus (n = 11,959), osteoarthritis (n = 4,040) and controls (n = 158,439) were used from the Netherlands Information Network of General Practice (LINH), a large nationally representative primary care based cohort. Data were analyzed using multi-level logistic regression analyses and corrected for age, gender, hypercholesterolemia and hypertension.ResultsCVD prevalence rates were significantly higher in inflammatory arthritis, diabetes mellitus and osteoarthritis compared with controls. These results attenuated - especially in diabetes mellitus - but remained statistically significant after adjustment for age, gender, hypertension and hypercholesterolemia for inflammatory arthritis (OR = 1.5 (1.2-1.9)) and diabetes mellitus (OR = 1.3 (1.2-1.4)). The association between osteoarthritis and CVD reversed after adjustment (OR = 0.8 (0.7-1.0)).ConclusionsThese results confirm an increased prevalence rate of CVD in inflammatory arthritis to levels resembling diabetes mellitus. By contrast, lack of excess CVD in osteoarthritis further suggests that the systemic inflammatory load is critical to the CVD burden in inflammatory arthritis.

Tumour necrosis factor blocking agents and progression of subclinical atherosclerosis in patients with ankylosing spondylitis

Background Ankylosing spondylitis (AS) is associated with an increased cardiovascular risk that might be due to the chronic underlying inflammatory process. We investigated whether subclinical atherosclerosis of the carotid artery in patients with AS was reduced after anti-inflammatory treatment with tumour necrosis factor (TNF) inhibitors in a prospective observational cohort study. Methods 67 out of 81 AS patients who used TNF inhibitors and underwent ultrasonography at baseline returned for follow-up after 4.9u2005years. Of all patients, 12 (15%) discontinued the use of TNF inhibitors. Assessments of medication use, AS-related factors and cardiovascular risk factors were measured at baseline and repeated at follow-up. B-mode carotid ultrasonography was used to investigate arterial wall parameters, including carotid intima-media thickness (cIMT) and Youngs elastic modulus (YEM). Results After a median 4.9u2005years of follow-up, cIMT did not change significantly (paired t test +0.011u2005mm, p=0.561) in those who continued the use of TNF inhibitors, while cIMT increased substantially (+0.057u2005mm, p=0.069) in those who did not continue their use of TNF inhibitors. The effect of TNF inhibitors was mainly mediated by a subsequent decrease in AS disease activity. Vascular elasticity (as measured with YEM) did not change significantly in patients who discontinued TNF inhibitors or those who continued TNF inhibitors. Conclusions The use of TNF inhibitors might stabilise or slow down the progression of subclinical atherosclerosis in AS patients, reflecting a decreased cardiovascular risk in these patients.

Subclinical renal dysfunction is independently associated with cardiovascular events in rheumatoid arthritis: the CARRÉ Study

Background Patients with rheumatoid arthritis (RA) have double the risk of cardiovascular (CV) disease, largely independently of traditional CV risk factors. Renal dysfunction is associated with CV morbidity and mortality in the general population, but data on this association in RA are lacking. Objective To investigate the association between renal function and CV events in RA. Methods The CARRÉ Study is an ongoing prospective cohort study of Dutch patients with RA, which records CV events. Glomerular filtration rate (GFR) was estimated with the abbreviated Modification of Diet in Renal Disease formula. Logistic regression determined the association between estimated GFR and the occurrence of CV events. Results 353 patients were followed for 3 years, and 23 (7%) had a CV event. Patients who had an event had a significantly lower baseline GFR than those who did not (59 vs 79 ml/min, p=0.001). This association remained significant after adjustment for traditional risk factors: in this analysis, a decrease in GFR of 5 ml/min was associated with a 30% (95% CI 7% to 59%) increase in the occurrence of CV events. During follow-up, an unfavourable change in GFR was noted in patients who later had a CV event compared with those who did not. Conclusion These data confirm that, in RA, renal dysfunction is associated with a higher risk of CV disease independently of traditional CV risk factors.

Different Type of Carotid Arterial Wall Remodeling in Rheumatoid Arthritis Compared with Healthy Subjects: A Case-Control Study

Objective. Rheumatoid arthritis (RA) is associated with an increased cardiovascular (CV) risk, but mechanisms behind this increased risk have not been fully elucidated. Carotid arterial remodeling is the change of structural properties in response to hemodynamic or metabolic factors aimed at keeping wall stress within certain limits. This process might become maladaptive when stress on the arterial wall increases beyond these limits. We investigated whether maladaptive carotid arterial remodeling is present in RA compared with control subjects. Methods. The 2 cohorts were 96 patients with RA and 274 healthy subjects, who were investigated cross-sectionally. Carotid intima-media thickness (cIMT) and interadventitial diameter (IAD) were assessed by B-mode carotid ultrasonography. Lumen diameter (LD), circumferential wall stress (CWS), and circumferential wall tension (CWT) were calculated. Linear regression analyses were used to investigate the association between presence of RA and carotid arterial remodeling. Results. Compared with healthy subjects, RA was associated with a 0.40 mm (9.3%) greater LD, 0.41 mm (7.8%) greater IAD, 10% higher CWS, and 8% higher CWT. The groups had comparable cIMT. Associations remained similar after exclusion of patients with prior CV disease and after adjustment for demographic factors and CV risk factors. Conclusion. RA is associated with maladaptive outward carotid arterial remodeling. These results are relevant because maladaptive outward remodeling is associated with plaque instability and rupture. These results indicate an alternative pathway, beyond the traditional CV risk factors, in RA that amplifies the CV risk.

Thrombin-activatable fibrinolysis inhibitor and its relation with inflammation in rheumatoid arthritis

Rheumatoid arthritis (RA) is associated with an excessive risk of cardiovascular morbidity and mortality, and inflammation appears to be the missing link explaining this markedly elevated risk.1 Inflammation is a potent inducer of coagulation and fibrinolysis and may contribute to atherosclerotic and thrombotic components of cardiovascular events.2 Thrombin-activatable fibrinolysis inhibitor (TAFI), a procarboxypeptidase in plasma, is a regulatory protein of the coagulation/fibrinolysis balance as well as inflammation. TAFIa, the activated form of TAFI, acts by removing C-terminal arginine and lysine residues from substrates such as fibrin degradation products, bradykinin and the anaphylatoxins C3a and C5a. Elevated TAFI levels may reflect an enhanced risk of developing cardiovascular …