Biomedical subjects

I van der Horst-Bruinsma

Publications and source records attributed to I van der Horst-Bruinsma.

4 recordsLinked to original sources

PubMed2006

Etanercept 50 mg once weekly is as effective as 25 mg twice weekly in patients with ankylosing spondylitis.

OBJECTIVE: To compare the efficacy, pharmacokinetics and safety of etanercept 50 mg once weekly with 25 mg twice weekly and placebo in patients with ankylosing spondylitis. METHODS: A 12-week, double-blind, placebo-controlled study compared the effects of etanercept 50 mg once weekly, etanercept 25 mg twice weekly and placebo in 356 patients with active ankylosing spondylitis (3:3:1 randomisation, respectively). The primary end point was the proportion of patients achieving a response at week 12 based on the Assessment in Ankylosing Spondylitis Working Group criteria (ASAS 20). The pharmacokinetics of etanercept 50 mg once weekly and 25 mg twice weekly were analysed. RESULTS: Baseline characteristics and disease activity were similar among the three groups: etanercept 50 mg once weekly, etanercept 25 mg twice weekly and placebo. The percentage of patients discontinuing therapy was 9.0%, 9.3% and 13.7% for the three respective groups. ASAS 20 response at 12 weeks was achieved by 74.2% of patients with etanercept 50 mg once weekly and 71.3% of those with etanercept 25 mg twice weekly, both significantly higher than the percentage of patients taking placebo (37.3%, p<0.001). Percentages of patients with ASAS 5/6 response (70.3%, 72.0% and 27.5%, respectively; p<0.001) and those with ASAS 40 response (58.1%, 53.3% and 21.6%, respectively; p<0.001) followed a similar pattern. Significant improvement (p<0.05) was seen in measures of disease activity, back pain, morning stiffness and C reactive protein levels as early as 2 weeks. Serum etanercept exposure was similar between the etanercept groups. Incidence of treatment-emergent adverse events, including infections, was similar among all three groups, and no unexpected safety issues were identified. CONCLUSIONS: Patients with ankylosing spondylitis can expect a comparable significant improvement in clinical outcomes with similar safety when treated with etanercept 50 mg once weekly or with 25 mg twice weekly.

Adult↗

PubMed2006

An international study on starting tumour necrosis factor-blocking agents in ankylosing spondylitis.

OBJECTIVES: To determine the type and proportion of patients with ankylosing spondylitis who rheumatologists consider to be candidates for treatment with tumour necrosis factor (TNF)-blocking agents, and to what extent this is in agreement with the ASsessment in Ankylosing Spondylitis (ASAS) international working group recommendations on initiation of treatment with anti-TNF agents. METHODS: Participants were rheumatologists from 10 different countries, who were considered to be experts in treating patients with ankylosing spondylitis and in the use of anti-TNF treatment, but were unaware of the ASAS recommendations (unpublished at the time of study in 2003). The first 10 consecutive patients with ankylosing spondylitis seen by the rheumatologist were evaluated as to whether the patient was a candidate for anti-TNF treatment. Thereafter, a metrologist assessed the patient for disease activity and severity, and collected data on demographics and treatment. RESULTS: Complete data were available for 1207 of the 1284 patients and were used for analysis. Overall, the rheumatologists indicated that they would initiate TNF-blocking agents in 49.3% of patients, ranging from 37.2% patients in Canada to 78.3% in Australia. These candidates had higher disease activity, higher levels of acute-phase reactants, worse spinal mobility, worse function, more often hip involvement and a higher prevalence of sick leave. Of all patients considered to be candidates, 40% did not fulfil ASAS recommendations with respect to previous use of non-steroidal anti-inflammatory drugs (NSAIDs; at least two NSAIDs) or Bath Ankylosing Spondylitis Disease Activity Index (>or=4). Conversely, 36% of patients who did not fulfil the NSAID or BASDAI recommendations were still considered to be candidates for TNF-blocking treatment. OBJECTIVE: variables, such as C reactive protein, erythrocyte sedimentation rate or magnetic resonance activity, were considered less important than disease activity in the decision on starting TNF-blocking drugs. The only important objective criterion was rapid radiographic progression. CONCLUSION: Rheumatologists wanted to initiate TNF-blocking drugs in roughly half of the patients with ankylosing spondylitis. However, there was a wide variation across countries and doctors. Rheumatologists considered both disease activity and severity to be determinants of starting TNF blockers, but their decision was often in disagreement with ASAS recommendations.

Adult↗

PubMed2001

Rhemulatologists' performance in dailiy practice.

OBJECTIVE: To assess rheumatologists' performance for 8 rheumatologic conditions and to explore possible explanatory factors. METHODS: After written informed consent was obtained, 27 rheumatologists (21% of all Dutch rheumatologists) practicing in 16 outpatient departments were each visited by 8 incognito "standardized patients" (SPs). The diagnoses of these 8 cases account for about 23% of all new referred patients in the Netherlands. Results for ordered lab tests as well as real radiographs with corresponding results from a radiologist were simulated. Information from the visits was obtained from the SPs, who completed predefined case-specific checklists, and by collecting data on resource utilization. Feedback was provided. RESULTS: Altogether 254 encounters took place, of which 201 were first visits and 53 were followup visits. SPs were unmasked twice during a visit. There was considerable variation in resource utilization (lab tests and imaging) between cases and between rheumatologists. Mean costs per rheumatologist ranged from US $ 4.67 to $ 65.36 per visit for lab tests and from US $ 33.15 to $ 226.84 per visit for imaging tests. No significant correlations were seen between resource utilization costs and number of years of clinical experience or performance on checklist scores. Rheumatologists with longer experience had lower total item checklist scores (r = -0.47; P < 0.05). CONCLUSION: A considerable variation in resource utilization was found among 27 Dutch rheumatologists. The information obtained is an excellent source for discussion on the appropriateness of care.

Adult↗

PubMed2001

Is disease severity in ankylosing spondylitis genetically determined?

OBJECTIVE: To assess the role of genes and the environment in determining the severity of ankylosing spondylitis. METHODS: One hundred seventy-three families with >1 case of ankylosing spondylitis were recruited (120 affected sibling pairs, 26 affected parent-child pairs, 20 families with both first- and second-degree relatives affected, and 7 families with only second-degree relatives affected), comprising a total of 384 affected individuals. Disease severity was assessed by the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) and functional impairment was determined using the Bath Ankylosing Spondylitis Functional Index (BASFI). Disease duration and age at onset were also studied. Variance-components modeling was used to determine the genetic and environmental components contributing to familiality of the traits examined, and complex segregation analysis was performed to assess different disease models. RESULTS: Both the disease activity and functional capacity as assessed by the BASDAI and the BASFI, respectively, were found to be highly familial (BASDAI familiality 0.51 [P = 10(-4)], BASFI familiality 0.68 [P = 3 x 10(-7)]). No significant shared environmental component was demonstrated to be associated with either the BASDAI or the BASFI. Including age at disease onset and duration of disease as covariates made no difference in the heritability assessments. A strong correlation was noted between the BASDAI and the BASFI (genetic correlation 0.9), suggesting the presence of shared determinants of these 2 measures. However, there was significant residual heritability for each measure independent of the other (BASFI residual heritability 0.48, BASDAI 0.36), perhaps indicating that not all genes influencing disease activity influence chronicity. No significant heritability of age at disease onset was found (heritability 0.18; P = 0.2). Segregation studies suggested the presence of a single major gene influencing the BASDAI and the BASFI. CONCLUSION: This study demonstrates a major genetic contribution to disease severity in ankylosing spondylitis. As with susceptibility to ankylosing spondylitis, shared environmental factors play little role in determining the disease severity.

Adolescent↗