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Featured researches published by Sjef van der Linden.


Arthritis & Rheumatism | 2001

Combined spa-exercise therapy is effective in patients with ankylosing spondylitis: a randomized controlled trial.

Astrid van Tubergen; Robert Landewé; Désirée van der Heijde; Alita Hidding; Nico Wolter; Max Asscher; Albrecht Falkenbach; Ekkehard Genth; Sjef van der Linden

OBJECTIVE To determine the efficacy of combined spa-exercise therapy in addition to standard treatment with drugs and weekly group physical therapy in patients with ankylosing spondylitis (AS). METHODS A total of 120 Dutch outpatients with AS were randomly allocated into 3 groups of 40 patients each. Group 1 (mean age 48 +/- 10 years; male:female ratio 25:15) was treated in a spa resort in Bad Hofgastein, Austria; group 2 (mean age 49 +/- 9 years; male:female ratio 28:12) in a spa resort in Arcen, The Netherlands. The control group (mean age 48 +/- 10 years; male:female ratio 34:6) stayed at home and continued their usual drug treatment and weekly group physical therapy during the intervention weeks. Standardized spa-exercise therapy of 3 weeks duration consisted of group physical exercises, walking, correction therapy (lying supine on a bed), hydrotherapy, sports, and visits to either the Gasteiner Heilstollen (Austria) or sauna (Netherlands). After spa-exercise therapy all patients followed weekly group physical therapy for another 37 weeks. Primary outcomes were functional ability, patients global well-being, pain, and duration of morning stiffness, aggregated in a pooled index of change (PIC). RESULTS Analysis of variance showed a statistically significant time-effect (P < 0.001) and time-by-treatment interaction (P = 0.004), indicating that the 3 groups differed over time with respect to the course of the PIC. Four weeks after start of spa-exercise therapy, the mean difference in PIC between group 1 and controls was 0.49 (95% confidence interval [CI] 0.16-0.82, P = 0.004) and between group 2 and controls was 0.46 (95% CI 0.15-0.78, P = 0.005). At 16 weeks, the difference between group 1 and controls was 0.63 (95% CI 0.23-1.02, P = 0.002) and between group 2 and controls was 0.34 (95% CI--0.05-0.73; P = 0.086). At 28 and 40 weeks, more improvement was found for group 1 compared with controls (P = 0.012 and P = 0.062, respectively) but not for group 2 compared with controls. CONCLUSION In patients with AS, a 3-week course of combined spa-exercise therapy, in addition to drug treatment and weekly group physical therapy alone, provides beneficial effects. These beneficial effects may last for at least 40 weeks.


Rheumatic Diseases Clinics of North America | 1998

ANKYLOSING SPONDYLITIS: Clinical Features

Sjef van der Linden; Désirée van der Heijde

The association between ankylosing spondylitis and human leukocyte antigen (HLA) B27 was reported for the first time in 1973. 34 This finding has stimulated quite a lot of research in many aspects of ankylosing spondylitis. However, the cause of the disease is still largely unknown. It has been postulated that an infectious agent ( possibly Klebsiella), in some way interacting with HLA-B27, may trigger the disease. 17 This theory is analogous to the situation in reactive arthritis or Reiters syndrome where bowel infection owing to certain Shigella, Salmonella, Yersinia, or Campylobacter strains may cause disease. Also, the association between ankylosing spondylitis and chronic inflammatory bowel diseases (Crohns disease and ulcerative colitis) has stimulated the idea that the causative agent in ankylosing spondylitis might belong to the (ubiquitous) bowel flora. This article briefly reviews the state of the art one quarter of a century later. It focuses on those topics that are most relevant from the clinical point of view.


Arthritis & Rheumatism | 2001

Inflammation and damage in an individual joint predict further damage in that joint in patients with early rheumatoid arthritis

Maarten Boers; Piet J. Kostense; Arco C. Verhoeven; Sjef van der Linden

UNLABELLED OBJECTIVE; Several factors predict joint damage in early rheumatoid arthritis (RA). In the context of a trial in early RA, we studied the relationship between clinical signs in individual joints and their propensity to develop progressive damage. METHODS The COBRA (Combinatietherapie Bij Reumatoide Artritis) multicenter trial compared the efficacy of prednisolone, methotrexate, and sulfasalazine against sulfasalazine alone in 155 patients with early RA. Two blinded observers interpreted radiographs in sequence (using the Sharp/Van der Heijde scoring system); in each center, one blinded observer performed clinical assessments every 3 months. The current analysis is based on clinical and radiologic data of the individual metacarpophalangeal (MCP) and proximal interphalangeal (PIP) joints of 135 patients. Conditional stepwise logistic regression analyzed the relationship between damage (progression) and clinical signs at baseline and followup for each of these joints individually in each patient. RESULTS Combination therapy strongly retarded the progression of damage. Progression was stronger in patients with rheumatoid factor, HLA-DR4, and high levels of disease activity at baseline. At baseline, 6% of the MCP and PIP joints showed damage; after 1 year, disease had progressed in 10% of these joints. Baseline damage, swelling, or pain in a joint independently and strongly predicted the progression of damage in that joint (P < 0.001). Each additional point in the swelling score (range 0-2) tripled the risk for subsequent progression. Each additional point on the Sharp scale (range 0-8 per joint) and each additional point on the pain scale (range 0-3) doubled the risk. The mean pain and swelling scores over the year were even stronger predictors of damage. CONCLUSION Local expression of early RA disease activity, both at baseline and at 1-year followup, is strongly related to progression of damage in the individual joint.


Arthritis Research & Therapy | 2005

Magnetic resonance imaging changes of sacroiliac joints in patients with recent-onset inflammatory back pain: inter-reader reliability and prevalence of abnormalities.

L Heuft-Dorenbosch; René Weijers; Robert Landewé; Sjef van der Linden; Désirée van der Heijde

To study the inter-reader reliability of detecting abnormalities of sacroiliac (SI) joints in patients with recent-onset inflammatory back pain by magnetic resonance imaging (MRI), and to study the prevalence of inflammation and structural changes at various sites of the SI joints.Sixty-eight patients with inflammatory back pain (at least four of the five following criteria: symptom onset before age 40, insidious onset, morning stiffness, duration >3 months, improvement with exercise — or three out of five of these plus night pain) were included (38% male; mean age, 34.9 years [standard deviation 10.3]; 46% HLA-B27-positive; mean symptom duration, 18 months), with symptom duration <2 years. A MRI scan of the SI joints was made in the coronal plane with the following sequences: T1-weighted spin echo, short-tau inversion recovery, T2-weighted fast-spin echo with fat saturation, and T1-spin echo with fat saturation after the administration of gadolinium. Both SI joints were scored for inflammation (separately for subchondral bone and bone marrow, joint space, joint capsule, ligaments) as well as for structural changes (erosions, sclerosis, ankylosis), by two observers independently. Agreement between the two readers was analysed by concordance and discordance rates and by kappa statistics.Inflammation was present in 32 SI joints of 22 patients, most frequently located in bone marrow and/or subchondral bone (29 joints in 21 patients). Readers agreed on the presence of inflammation in 85% of the cases in the right SI joint and in 78% of the cases in the left SI joint. Structural changes on MRI were present in 11 patients. Ten of these 11 patients also showed signs of inflammation.Agreement on the presence or absence of inflammation and structural changes of SI joints by MRI was acceptable, and was sufficiently high to be useful in ascertaining inflammatory and structural changes due to sacroiliitis. About one-third of patients with recent-onset inflammatory back pain show inflammation, and about one-sixth show structural changes in at least one SI joint.


BMC Musculoskeletal Disorders | 2008

Evaluation of patients with a recent clinical fracture and osteoporosis, a multidisciplinary approach.

Bianca Dumitrescu; Svenjhalmar van Helden; Rene ten Broeke; Arie Nieuwenhuijzen-Kruseman; Caroline E. Wyers; Gabriela Udrea; Sjef van der Linden; Piet Geusens

The aetiology of osteoporotic fractures is multifactorial, but little is known about the way to evaluate patients with a recent clinical fracture for the presence of secondary osteoporosis.The purpose of this study was to determine the prevalence of contributors to secondary osteoporosis in patients presenting with a clinical vertebral or non-vertebral fracture. Identifying and correcting these contributors will enhance treatment effect aimed at reducing the risk of subsequent fractures.In a multidisciplinary approach, including evaluation of bone and fall-related risk factors, 100 consecutive women (n = 73) and men (n = 27) older than 50 years presenting with a clinical vertebral or non-vertebral fracture and having osteoporosis (T-score ≤-2.5) were further evaluated clinically and by laboratory testing for the presence of contributors to secondary osteoporosis.In 27 patients, 34 contributors were previously known, in 50 patients 52 new contributors were diagnosed (mainly vitamin D deficiency in 42) and 14 needed further exploration because of laboratory abnormalities (mainly abnormal thyroid stimulating hormone in 9). The 57 patients with contributors were older (71 vs. 64 yrs, p < 0.01), had more vertebral deformities (67% vs. 44%, p < 0.05) and a higher calculated absolute 10-year risk for major (16.5 vs. 9.9%, p < 0.01) and for hip fracture (6.9 vs. 2.4%, p < 0.01) than patients without contributors. The presence of contributors was similar between women and men and between patients with fractures associated with a low or high-energy trauma.We conclude that more than one in two patients presenting with a clinical vertebral or non-vertebral fracture and BMD-osteoporosis have secondary contributors to osteoporosis, most of which were correctable. Identifying and correcting these associated disorders will enhance treatment effect aimed at reducing the risk of subsequent fractures in patients older than 50 years.


Medical Education | 2002

Reproducibility of clinical performance assessment in practice using incognito standardized patients

Simone L. Gorter; Jan-Joost Rethans; Désirée van der Heijde; Albert Scherpbier; Harry Houben; Cees van der Vleuten; Sjef van der Linden

Background  The reproducibility of authentic assessment methods has been investigated for objective structured clinical examinations (OSCEs) and video assessment in general practice, but not for assessment with incognito standardized patients.


European Journal of Pain | 1999

Principles of economic evaluation for interventions of chronic musculoskeletal pain.

M. Goossens; Silvia M. A. A. Evers; Johan Vlaeyen; Maureen Rutten-van Mölken; Sjef van der Linden

Economic evaluation is attracting increasing attention to inform policy makers, insurers and other payers of the value of existing and new treatment modalities. Hence, it is desirable to assess not only the medical but also the economic consequences the new treatments produce. The available literature on economic evaluation revealed an urgent need for sound economic evaluation studies in the field of chronic musculoskeletal pain. Due to the generally weak methodology, the intended purpose of economic evaluation to help set funding priorities has often been bypassed. Although in general therapists have no direct responsibility for allocating scarce resources in the field of musculoskeletal pain, they are confronted with the results of these decisions in their everyday work. A clear understanding of the main principles of economic evaluation studies might therefore be advantageous. This paper addresses important methodological issues in economic evaluation research, such as the techniques for economic evaluation studies and the analytic perspective. In addition, the paper pays attention to the inclusion of costs and outcomes in economic evaluation research, sensitivity analysis, discounting, incremental analysis and ratios, and collecting of data.


Annals of the Rheumatic Diseases | 2007

How do the EQ-5D, SF-6D and the well-being rating scale compare in patients with ankylosing spondylitis?

Annelies Boonen; Désirée van der Heijde; Robert Landewé; Astrid van Tubergen; Herman Mielants; Maxime Dougados; Sjef van der Linden

Purpose: To compare aspects of validity of EuroQol—5 Dimensions (EQ-5D) and Short-Form—6 Dimensions (SF-6D), two indirect utility instruments, and the well-being rating scale (RS) in ankylosing spondylitis (AS). Methods: EQ-5D, SF-6D and RS were available for 254 patients fulfilling modified New York criteria. 134 patients were part of an observational cohort and 120 were part of a randomised controlled trial (RCT). Aspects of validity assessed were truth (agreement and correlation with external health measures) and discrimination (differentiation between health states, repeatability and detection of treatment effect). Results: Median (range) values were 0.69 (−0.08–1.00) for the EQ-5D, 0.65 (0.35–0.95) for the SF-6D and 0.65 (0.14–1.00) for the RS. Agreement (intraclass correlation coefficient) was moderate (0.46–0.55). Instruments correlated equally with disease activity, functioning and quality of life. The SF-6D showed smaller average differences in utility between patients with better and worse disease compared with the EQ-5D and the RS. The smallest detectable difference (SDD) (in the control group of RCT) was 0.36, 0.17 and 0.33 for EQ-5D, SF-6D and RS, respectively. The ability to detect treatment effect (in the intervention trial) showed standardised effect sizes that were moderate for EQ-5D and SF-6D (0.63 and 0.64) and low for the RS (0.23). Conclusion: In patients with AS, EQ-5D, SF-6D and the RS correlate equally well with external measures of health, but have different psychometric properties. The SDD is most favourable for the SF-6D, but it discriminates less well between patients with different disease severities. The RS has a poorer ability to detect treatment effects. It is difficult to recommend one of the instruments.


Arthritis & Rheumatism | 2001

Rheumatologists' performance in daily practice

Simone L. Gorter; Sjef van der Linden; Jolanda Brauer; Désirée van der Heijde; Harry Houben; Jan-Joost Rethans; Albert Scherpbier; Cees van der Vleuten; Annelies Boonen; Ed N. Griep; Irene E. van der Horst-Bruinsma; Annelies Linssen; Marijke van Santen‐Hoeufft; Hille van der Tempel; Toon Westgeest

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


Current Rheumatology Reports | 2015

The ASAS Criteria for Axial Spondyloarthritis: Strengths, Weaknesses, and Proposals for a Way Forward

Sjef van der Linden; Nurullah Akkoc; Matthew A. Brown; Philip C. Robinson; Muhammad Asim Khan

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Désirée van der Heijde

Leiden University Medical Center

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Maarten Boers

VU University Medical Center

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Muhammad Asim Khan

Case Western Reserve University

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