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D van der Heijde

Publications and source records attributed to D van der Heijde.

At least 19 recordsLinked to original sources
PubMed2003

Development of the ASQoL: a quality of life instrument specific to ankylosing spondylitis.

BACKGROUND: Although disease-specific health status measures are available for ankylosing spondylitis (AS), no instrument exists for assessing quality of life (QoL) in the condition. OBJECTIVE: To produce an AS-specific QoL measure that would be relevant and acceptable to respondents, valid, and reliable. METHODS: The ASQoL employs the needs-based model of QoL and was developed in parallel in the UK and the Netherlands (NL). Content was derived from interviews with patients in each country. Face and content validity were assessed through patient field test interviews (UK and NL). A postal survey in the UK produced a more efficient version of the ASQoL, which was tested for scaling properties, reliability, internal consistency, and validity in a further postal survey in each country. RESULTS: A 41 item questionnaire was derived from interview transcripts. Field testing interviews confirmed acceptability. Rasch analysis of data from the first survey (n=121) produced a 26 item questionnaire. Rasch analysis of data from the second survey (UK: n=164; NL: n=154) showed some item misfit, but showed that items formed a hierarchical order and were stable over time. Problematic items were removed giving an 18 item scale. Both language versions had excellent internal consistency (alpha=0.89-0.91), test-retest reliability (r(s)=0.92 UK and r(s)=0.91 NL), and validity. CONCLUSIONS: The ASQoL provides a valuable tool for assessing the impact of interventions for AS and for evaluating models of service delivery. It is well accepted by patients, taking about four minutes to complete, and has excellent scaling and psychometric properties.

Adult↗
PubMed2003

Assessment of enthesitis in ankylosing spondylitis.

OBJECTIVE: To assess, firstly, the validity of the enthesis index published by Mander (Mander enthesis index (MEI)) and, secondly, to investigate whether it is possible to define a new enthesis index that is less time consuming to perform with at least similar or better properties. METHODS: Data from the OASIS cohort, an international, longitudinal, observational study on outcome in ankylosing spondylitis, were used. In this study, measures of disease activity, including the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) and the MEI, were assessed regularly in 217 patients. With the MEI, for each measurement period independently, a process of data reduction was performed to identify the entheses most commonly reported as painful by the patients. A more concise enthesis index was constructed with aid of the entheses found in this way. Correlations with measures of disease activity were used to test the validity of several entheses indices. RESULTS: Reduction of the number of entheses from 66 to 13 and omitting grading of the intensity of pain resulted in an index which was named the "Maastricht Ankylosing Spondylitis Enthesitis Score" (MASES). The MASES (range 0-13) has much greater feasibility than the MEI (range 0-90). However, up to 21% of patients with a score >0 on the MEI were not identified by a score on the MASES >0. Only 2.1% of the patients with an original enthesis score >0 had an original score on the MEI >3 (range 0-90) and it can be questioned whether a low score on the MEI index represents clinically important enthesitis. The Spearman correlation coefficient between the MASES score and the MEI was 0.90 and between the MASES and the BASDAI was 0.53 compared with a correlation of 0.59 between the MEI and the BASDAI. CONCLUSIONS: MASES seems to be a good alternative to the MEI with much better feasibility.

Adult↗
PubMed2003

Assessment of disability with the World Health Organisation Disability Assessment Schedule II in patients with ankylosing spondylitis.

OBJECTIVE: To investigate in ankylosing spondylitis (AS) whether the newly developed World Health Organisation Disability Assessment Schedule II (WHODAS II) is a useful instrument for measuring disability, to assess its responsiveness in relation to other traditional disease specific instruments, and to identify factors that are associated with both short term and long term scores on the WHODAS II. METHODS: Patients with AS from a randomised controlled trial assessing the efficacy of spa treatment (n=117) and from a five year longitudinal observational study (n=97) participated. The patients completed several questionnaires, including the WHODAS II. After a three week course of spa treatment, 31 patients again completed all questionnaires to assess responsiveness. To determine to what degree the WHODAS II reflects some AS oriented measures on disease activity, functioning, and quality of life, correlation coefficients between the WHODAS II and these other questionnaires were calculated. Responsiveness was calculated by the effect size (ES) and standardised response mean (SRM). Linear regression analysis was performed to explore which factors might be associated with short term changes on the WHODAS II and to investigate (in the observational study) which factors of WHODAS II might predict disability five years later. RESULTS: Mean score on the WHODAS II was 23.9 (SD 15.5 (range 0.0-76.1)). Scores on the WHODAS II were significantly correlated with all disease specific questionnaires measured (all p<0.001). The WHODAS II showed a comparable short term responsiveness score (SRM 0.41; ES 0.39). In regression analysis these short term changes on the WHODAS II were significantly associated with changes in functioning (beta coefficient 4.25, 95% confidence interval (95% CI) 1.24 to 7.26, p=0.007). In the observational study, disease activity (beta coefficient 0.35, 95% CI 0.17 to 0.53, p<0.000) as well as functioning (beta coefficient 0.23, 95% CI 0.09 to 0.38, p=0.002) seemed to significantly predict disability (WHODAS II) after five years. CONCLUSION: The WHODAS II is a useful instrument for measuring disability in AS in that it accurately reflects disease specific instruments and that it shows similar responsiveness scores. In AS, a short term change on the WHODAS II is associated with a change in physical function. At the group level, disease activity and physical functioning may predict disability after five years.

Activities of Daily Living↗
PubMed2003

Comparison of statistically derived ASAS improvement criteria for ankylosing spondylitis with clinically relevant improvement according to an expert panel.

OBJECTIVE: To investigate whether the recently developed (statistically derived) "ASsessment in Ankylosing Spondylitis Working Group" improvement criteria (ASAS-IC) for ankylosing spondylitis (AS) reflect clinically relevant improvement according to the opinion of an expert panel. METHODS: The ASAS-IC consist of four domains: physical function, spinal pain, patient global assessment, and inflammation. Scores on these four domains of 55 patients with AS, who had participated in a non-steroidal anti-inflammatory drug efficacy trial, were presented to an international expert panel (consisting of patients with AS and members of the ASAS Working Group) in a three round Delphi exercise. The number of (non-)responders according to the ASAS-IC was compared with the final consensus of the experts. The most important domains in the opinion of the experts were identified, and also selected with discriminant analysis. A number of provisional criteria sets that best represented the consensus of the experts were defined. Using other datasets, these clinically derived criteria sets as well as the statistically derived ASAS-IC were then tested for discriminative properties and for agreement with the end of trial efficacy by patient and doctor. RESULTS: Forty experts completed the three Delphi rounds. The experts considered twice as many patients to be responders than the ASAS-IC (42 v 21). Overall agreement between experts and ASAS-IC was 62%. Spinal pain was considered the most important domain by most experts and was also selected as such by discriminant analysis. Provisional criteria sets with an agreement of >or=80% compared with the consensus of the experts showed high placebo response rates (27-42%), in contrast with the ASAS-IC with a predefined placebo response rate of 25%. All criteria sets and the ASAS-IC discriminated well between active and placebo treatment (chi(2)=36-45; p<0.001). Compared with the end of trial efficacy assessment, the provisional criteria sets showed an agreement of 71-82%, sensitivity of 67-83%, and specificity of 81-88%. The ASAS-IC showed an agreement of 70%, sensitivity of 62%, and specificity of 89%. CONCLUSION: The ASAS-IC are strict in defining response, are highly specific, and consequently show lower sensitivity than the clinically derived criteria sets. However, those patients who are considered as responders by applying the ASAS-IC are acknowledged as such by the expert panel as well as by patients' and doctors' judgments, and are therefore likely to be true responders.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed2003

Radiographic assessment of sacroiliitis by radiologists and rheumatologists: does training improve quality?

OBJECTIVE: To assess performance of radiologists and rheumatologists in detecting sacroiliitis METHODS: 100 rheumatologists and 23 radiologists participated. One set of films was used for each assessment, another for training, and the third for confidence judgment. Films of HLA-B27+ patients with AS were used to assess sensitivity. For specificity films of healthy HLA-B27- relatives were included. Plain sacroiliac (SI) films with simultaneously taken computed tomographic scans (CTs) were used for confidence judgment. Three months after reading the training set, sensitivity and specificity assessments were repeated. Next, participants attended a workshop. They also rated 26 SI radiographs and 26 CTs for their trust in each judgment. Three months later final assessments were done. RESULTS: Sensitivity (84.3%/79.8%) and specificity (70.6%/74.7%) for radiologists and rheumatologists were comparable. Rheumatologists showed 6.3% decrease in sensitivity after self education (p=0.001), but 3.0% better specificity (p=0.008). The decrease in sensitivity reversed after the workshop. Difference in sensitivity three months after the workshop and baseline was only 0.5%. Sensitivity <50% occurred in 13% of participants. Only a few participants showed changes of >5% in both sensitivity and specificity. Intraobserver agreement for sacroiliitis grade 1 or 2 ranged from 65% to 100%. Sensitivity for CT (86%) was higher than for plain films (72%) (p<0.001) with the same specificity (84%). Confidence ratings for correctly diagnosing presence (7.7) or absence (8.3) of sacroiliitis were somewhat higher than incorrectly diagnosing the presence (6.6) or absence (7.4) of sacroiliitis (p<0.001). CONCLUSION: Radiologists and rheumatologists show modest sensitivity and specificity for sacroiliitis and sizeable intraobserver variation. Overall, neither individual training nor workshops improved performance.

Adult↗
PubMed2003

Direct costs of ankylosing spondylitis and its determinants: an analysis among three European countries.

OBJECTIVE: To assess direct costs associated with ankylosing spondylitis (AS). To determine which variables, including country, predict costs. METHODS: 216 patients with AS from the Netherlands, France, and Belgium participated in a two year observational study and filled in bimonthly economic questionnaires. Disease related healthcare resource use was measured and direct costs were calculated from a societal perspective (true cost estimates) and from a financial perspective (country-specific tariffs). Predictors of costs were assessed using Cox's regression analysis. RESULTS: 209 patients provided sufficient data for cost analysis. Mean annual societal direct costs for each patient were euro;2640, of which 82% were direct healthcare costs. In univariate analysis costs were higher in the Netherlands than in Belgium, but this difference disappeared after adjusting for baseline differences in patients' characteristics among countries. Longer disease duration, lower education, worse physical function, and higher disease activity were predictors of costs. Mean annual direct costs from a financial perspective were euro;2122, euro;1402, and euro;941 per patient in the Netherlands, France, and Belgium, respectively. For each country, costs from a financial perspective were significantly lower than costs from a societal perspective. CONCLUSION: Direct costs for AS are substantial in three European countries but not significantly different after adjusting for baseline characteristics among countries. Worse physical function and higher disease activity are important determinants of costs, suggesting better disease control might reduce the costs of AS. The difference in costs from a societal and financial perspective emphasises the importance of an economic analysis.

Adolescent↗
PubMed2003

Costs of ankylosing spondylitis in three European countries: the patient's perspective.

OBJECTIVE: To assess a patient's out of pocket costs, income loss, time consumption, and quality of life (QoL) due to ankylosing spondylitis (AS) in three European countries and to assess variables predicting these outcomes. METHODS: 216 patients with AS from the Netherlands, France, and Belgium participated in a two year study. Health resource use, days absent from work, time lost, and quality of life (EuroQol) were assessed by bimonthly questionnaires. AS related healthcare and non-healthcare expenditure and income loss were calculated taking into account country-specific regulations. Predictors of costs, time consumption, and QoL were analysed by Cox's regression. RESULTS: 209 patients provided data for cost analysis. Average annual healthcare and non-healthcare expenditure was euro;431 per patient and average annual income loss was euro;1371 per patient. Healthcare costs were highest for Belgian and lowest for French patients, while non-healthcare costs were highest for Dutch patients. A patient's total costs were associated with higher age and worse physical function. On average, patients with AS needed 75 minutes additional time a day because of AS. Worse physical function and higher disease activity predicted time consumption. After adjusting for baseline confounders, QoL was worse in Belgian and French than in Dutch patients. Peripheral arthritis, worse physical function, higher disease activity, and loss of income contributed to worse QoL. CONCLUSION: AS is time consuming and associated with substantial out of pocket costs. Belgian patients incur the highest healthcare payments. Poor physical function increases patient's costs and time consumption. Loss of income is associated with lower QoL.

Adolescent↗
PubMed2003

Initiation of biological agents in patients with ankylosing spondylitis: results of a Delphi study by the ASAS Group.

BACKGROUND: There is ample evidence of important symptomatic efficacy of tumour necrosis factor alpha (TNFalpha) inhibition in ankylosing spondylitis (AS). Moreover, studies suggest that anti-TNF could be considered as the first disease controlling antirheumatic treatment (DC-ART) for AS. OBJECTIVE: To determine precisely which patients with AS are most likely to benefit from anti-TNFalpha treatment because of the cost and possible long term side effects of such treatment. METHODS: Assessment in Ankylosing Spondylitis (ASAS) members were asked to use a Delphi technique to name the characteristics of patients with AS for whom they would start DC-ART, in three different clinical presentations (isolated axial involvement, peripheral arthritis, enthesitis). RESULTS: Among the 62 invited ASAS members, more than 50% actively participated in the four phases of definition according to the Delphi technique. For each of the three clinical presentations, a combination of five to six domains was proposed, with an evaluation instrument and a cut off point defining a minimum level of activity for each domain. CONCLUSION: This study provides a profile for a patient with AS for considering initiation of biological agents that reflects the opinion of the ASAS members, using a Delphi exercise. Further studies are required to assess their relevance and their consistency with clinical practice.

Antibodies, Monoclonal↗
PubMed2003

International ASAS consensus statement for the use of anti-tumour necrosis factor agents in patients with ankylosing spondylitis.

OBJECTIVE: To obtain an international consensus about the use of anti-tumour necrosis factor alpha (anti-TNF alpha) for treating patients with ankylosing spondylitis (AS). METHODS: These recommendations were developed by a review of published reports in combination with expert opinion, including a Delphi exercise, and a consensus meeting of the ASsessments in AS (ASAS) Working Group. RESULTS: The final consensus comprises the following requirements: (1) For the initiation of anti-TNF alpha therapy: (a) a diagnosis of definitive AS; (b) presence of active disease for at least four weeks as defined by both a sustained Bath AS Disease Activity Index (BASDAI) of at least 4 and an expert opinion based on clinical features, acute phase reactants, and imaging modalities; (c) presence of refractory disease defined by failure of at least two non-steroidal anti-inflammatory drugs during a single three month period, failure of intra-articular steroids if indicated, and failure of sulfasalazine in patients with peripheral arthritis; (d) application and implementation of the usual precautions and contraindications for biological therapy. (2) For the monitoring of anti-TNF alpha therapy: both the BASDAI and the ASAS core set for clinical practice should be followed regularly. (3) For the discontinuation of anti-TNF alpha therapy: in non-responders, consideration should be made after 6-12 weeks' treatment. Response is defined as improvement of (a) at least 50% or 2 units (on a 0-10 scale) of the BASDAI, (b) expert opinion that treatment should be continued. CONCLUSION: This consensus statement on anti-TNF alpha treatment in AS may be used for guidance in clinical decision making and as the basis for the development of guidelines. Evaluation of the healthcare consequences of this consensus is subject to further research by the ASAS group.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed2002

Work status and productivity costs due to ankylosing spondylitis: comparison of three European countries.

OBJECTIVE: To compare work disability, sick leave, and productivity costs due to ankylosing spondylitis (AS) of three European countries. METHODS: 216 patients with AS from the Netherlands, France, and Belgium participated in a two year observational study. Employment and work disability rates at baseline were adjusted for age and sex. Productivity costs were calculated by both the friction cost method and the human capital approach. The adjusted contributions of country to employment, work disability, and having an episode of sick leave were assessed by logistic regression and the contribution of the country to days of sick leave and costs by Cox proportional hazard analysis. RESULTS: 209 patients completed the two years' follow up with sufficient data for cost analysis. Adjusted employment was 55% in the Netherlands as compared with 72% in both other countries and only in the Netherlands was it lower than expected in the general population. Adjusted work disability was 41%, 23%, and 9% in the Netherlands, France, and Belgium and in all countries was higher than expected in the general population. In those with a paid job, the mean number of days of sick leave per patient per year because of AS was 19 (range 0-130), six (range 0-77), and nine (range 0-60 ) in the Netherlands, France, and Belgium respectively. Applying the friction cost method to those with a paid job resulted in mean costs per patient per year of 1257 euros (range 0-7356), 428 euros (range 0-5979), and 476 euros (range 0-2354) in the Netherlands, France, and Belgium. Applying the human capital approach to the whole group resulted in mean costs per patient per year of 8862 euros (range 0-46 818), 3188 euros (range 0-43 550), and 3609 euros (range 0-34 320) in the three countries, respectively. After adjusting for sociodemographic and disease characteristics, living in the Netherlands, as compared with both other countries, was associated with a higher chance of being work disabled (odds ratio (OR)=3.82; 95% confidence interval (CI) 1.33 to 11.01), but not with the risk of having an episode of sick leave. Similarly, living in the Netherlands contributed independently to the number of days sick leave (OR=0.65; 95% CI 0.43 to 0.97), a higher amount of friction costs (OR=0.63; 95% CI 0.42 to 0.96), and a higher amount of human capital costs (OR=0.46; 95% CI 0.32 to 0.68). CONCLUSION: There are remarkable differences in work status and productivity costs between the three European countries. This has implications for the generalisability of health economic studies.

Adult↗
PubMed2002

Reliability of self assessed joint counts in ankylosing spondylitis.

OBJECTIVE: To determine the reliability of self reported joint counts to assess pain or swelling in ankylosing spondylitis (AS). METHODS: 217 outpatients fulfilling the modified New York criteria for AS were asked to mark painful joints and swollen joints on two mannequins presenting 44 and 40 joints respectively. A doctor or research nurse assessed the same joints for pain and swelling on the same day, after completion by the patient, without information on the results of the patient's assessment. RESULTS: Forty six (21%) patients reported one or more swollen joints (mean number of swollen joints 0.5, range 0-8); the doctor found one or more swollen joints in 54 (25%) of the patients (mean number of swollen joints 0.8, range 0-31). The overall agreement on the number of swollen joints between patients and doctor was moderate (intraclass correlation coefficient (ICC) 0.53). Agreement on individual swollen joints was poor to moderate (kappa 0.1-0.64). 128 (60%) patients reported tender joints (mean number of joints 2.4, range 0-26). The doctors reported one of more tender joints in 50% of the patients (mean number of tender joints 2.2, range 0-34). The overall agreement was also moderate (ICC 0.71). The agreement on individual tender joints was again poor to moderate (kappa 0.19-0.43). There was only high concordance between doctors and patients on the absence of swollen joints (82%). The concordance on the presence of monoarthritis, oligoarthritis, or polyarthritis was low (17-22%). CONCLUSION: Owing to these discrepancies in assessment of individual joints and total number of affected joints, joint counts in AS assessed by doctors cannot be replaced by joint counts reported by the patients. Patients are only able to judge if their joints are not swollen.

Adolescent↗
PubMed2002

Staging of patients with ankylosing spondylitis: a preliminary proposal.

Patients with ankylosing spondylitis (AS) are characterised by a wide range of clinical presentations, radiographic profiles, and outcomes, which are not well differentiated by current diagnostic and classification systems for the disorder. Inadequacies in these systems may limit clinicians' ability to manage their patients with AS appropriately and act as an obstacle to reasonable comparison of therapeutic trial results. A standardised staging system for AS is therefore proposed that would provide a more detailed categorisation of patients based on assessment of structural damage, peripheral joint and organ involvement, presence of concomitant diseases, and the severity and extent of disease activity and functional impairment. The proposed system needs to be evaluated closely and amended as needed to assure its usefulness in clinical and research settings.

Anti-Inflammatory Agents↗
PubMed2002

Treatment trials in ankylosing spondylitis: current and future considerations.

Emerging treatment options in ankylosing spondylitis (AS) are giving new hope to patients with this chronic and potentially disabling disease. Clinical development of new treatments requires that rigorous and well controlled trials be conducted to demonstrate safety and efficacy. A number of classification systems have been developed in recent years as a result of enhanced understanding of the pathogenesis of AS. Although new outcome measures have been developed and a consensus has been reached on the use of assessment instruments in clinical trials, there is still need for improvement and implementation. The ASsessments in Ankylosing Spondylitis (ASAS) Working Group has addressed some of these dilemmas by establishing a core set of domains for the evaluation of AS and by selecting specific assessment methods for each domain. They have also published improvement criteria for assessing short term improvement with symptom modifying antirheumatic drugs and are presently in the process of developing response criteria for disease controlling antirheumatic treatment. Various experts are also currently examining discrepancies and inadequacies of classification systems for AS. Imaging studies, magnetic resonance imaging, in particular, may provide better classification criteria in the near future. In addition to consensus on outcome assessment and classification of AS, lessons learnt from clinical trials in rheumatoid arthritis (RA) may serve as a template for AS. Guidance provided by the United States Food and Drug Administration (FDA) for clinical trials in RA may be of particular use. The FDA has defined the claims that sponsors can receive for RA products and the clinical trial data that would be expected to be submitted to support such claims.

Acute-Phase Proteins↗
PubMed2002

Imaging and scoring in ankylosing spondylitis.

Ankylosing spondylitis (AS) is the prototype of the spondyloarthritides (SpA). AS is a disease subset but also a possible outcome of SpA. Early diagnosis of sacroiliitis, the most frequent clinical symptom frequently accompanied by inflammatory back pain and other inflammatory lesions of the spine such as spondylitis and spondylodiscitis, can be visualized early by magnetic resonance imaging (MRI). Spinal inflammation can be demonstrated by MRI using either the fat-saturating short tau inversion recovery (STIR) technique or by application of the contrast agent gadolinium-diethylenetriamine pentaacetic acid (DTPA). This is especially useful in early and active disease, in young women and in children, and for the differential diagnosis of septic sacroiliitis. Because of the efficacy of the novel biological agents directed against tumour necrosis factor-alpha (TNF-alpha) - such as infliximab and etanercept - in SpA there is a need for spinal imaging techniques more sensitive than conventional X-rays. The available scoring tools are reviewed and novel approaches using MRI are presented.

Adult↗