M.A.F.J. van de Laar
University of Twente
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Annals of the Rheumatic Diseases | 1997
Carola J. E. Kaandorp; Huibert J. Dinant; M.A.F.J. van de Laar; H J Moens; A P. A Prins; B A C Dijkmans
OBJECTIVES To determine the incidence and sources of bacterial arthritis in the Amsterdam health district and the maximum percentage of cases that theoretically would be preventable. METHODS Patients with bacterial arthritis diagnosed between 1 October 1990 and 1 October 1993 were prospectively reported to the study centre by all 12 hospitals serving the district. Data were gathered on previous health status, source of infection, and microorganisms involved. RESULTS 188 episodes of bacterial arthritis were found in 186 patients. Most of the 38 children were previously healthy. Fifty per cent of the adults were 65 years or older. Of the adults 84% had an underlying disease, in 59% a joint disorder. Joint surgery constituted the largest part of direct infections (33%) and skin defects were the most important source of haematogenous infections (67%). Infection of joints containing prosthetic or osteosynthetic material by a known haematogenous source occurred 15 times (8%).Staphylococcus aureus was the causative organism in 44% of all positive cultures. CONCLUSION The incidence of bacterial arthritis was 5.7 per 100 000 inhabitants per year. Preventive measures directed to patients with prosthetic joints or osteosynthetic material, and a known haematogenous source would have prevented at most 8% of all cases.
Annals of the Rheumatic Diseases | 2003
M. Hoekstra; A. E. van Ede; C.J. Haagsma; M.A.F.J. van de Laar; Tom W J Huizinga; Marijn W.M. Kruijsen; R.F.J.M. Laan
Objective: To study factors associated with toxicity, final dose, and efficacy of methotrexate (MTX) in patients with rheumatoid arthritis (RA). Methods: Data were used from a randomised clinical 48 week trial on 411 patients with RA all treated with MTX, comparing folates and placebo. Logistic regression was used to study the relation between baseline variables and various dependent factors, including hepatotoxicity (alanine aminotransferase ⩾3×upper limit of normal), MTX withdrawal, final MTX dose ⩾15 mg/week, and MTX efficacy. Results: Addition of folates to MTX treatment was strongly related to the lack of hepatotoxicity. Next to this, high body mass index was related to the occurrence of hepatotoxicity. Prior gastrointestinal (GI) events and younger age were related to the adverse event, diarrhoea. Hepatotoxicity and GI adverse events were the main reason for MTX withdrawal, which in turn was associated with the absence of folate supplementation, body mass index, prior GI events, and female sex. Renal function (creatinine clearance ⩾50 ml/min) was not associated with toxicity. Reaching a final dose of MTX of ⩾15 mg/week was related to folate supplementation and the absence of prior GI events. Efficacy of MTX treatment was associated with low disease activity at baseline, male sex, use of non-steroidal anti-inflammatory drugs (NSAIDs), and lower creatinine clearance. Conclusions: MTX toxicity, final dose, and efficacy are influenced by folate supplementation. Baseline characteristics predicting the outcome of MTX treatment are mainly prior GI events, body mass index, sex, use of NSAIDs, and creatinine clearance.
Annals of the Rheumatic Diseases | 2009
M.K. Reinders; Cees J. Haagsma; T.L.Th.A. Jansen; van Eric Roon; J Delsing; M.A.F.J. van de Laar; Jacobus Brouwers
Objectives: To compare the efficacy and tolerability of allopurinol 300–600 mg/day versus benzbromarone 100–200 mg/day used to attain a target serum urate concentration (sUr) ⩽0.30 mmol/l (5 mg/dl). Methods: A randomised, controlled, open-label, multicentre trial in gout patients with renal function defined as a calculated creatinine clearance ⩾50 ml/min. Patients were treated with 300 mg allopurinol or 100 mg benzbromarone once a day (stage 1). If sUr ⩽0.30 mmol/l was not attained after 2 months, the dose was doubled to allopurinol 300 mg twice a day or benzbromarone 200 mg once a day (stage 2). The primary end point was treatment success in either of the two stages, defined as clinical tolerability and attainment of biochemical target sUr. Results: Sixty-five patients were enrolled in stage 1; 36 received allopurinol and 29 received benzbromarone. Fifty-five patients (85%) were analysed at stage 1: the success rates were 8/31 (26%) and 13/25 (52%), respectively, and the difference was −0.26 (95% CI from −0.486 to −0.005), p = 0.049. At stage 2, the success rates were 21/27 (78%) and 18/23 (78%), respectively, and the difference was −0.005 (95% CI from −0.223 to 0.220), p = 1.00. Two patients stopped receiving allopurinol and three stopped receiving benzbromarone because of adverse drug reactions. Conclusions: Increasing the allopurinol dose from 300 to 600 mg/day and the benzbromarone dose from 100 to 200 mg/day according to the target sUr produced significantly higher success rates (both 78% successful in attaining sUr ⩽0.30 mmol/l). No significant differences in treatment success between benzbromarone and allopurinol were found after dose escalation. Trial registration number: ISRCTN49563848).
The Lancet | 1996
S. ten Wolde; F. C. Breedveld; B A C Dijkmans; J. Hermans; J.P. Vandenbroucke; M.A.F.J. van de Laar; H.M. Markusse; M. Janssen; H.R. van den Brink
BACKGROUND A favourable benefit/risk ratio for treatment of rheumatoid arthritis (RA) with second-line drugs has been established only in short-term studies. The present investigation addresses the question of whether RA patients with a good response to long-term treatment with second-line drugs benefit from continuation of such treatment. METHODS A 52-week randomised double-blind placebo-controlled multicentre study was conducted to assess the effect of stopping second-line therapy in 285 RA patients with a good long-term therapeutic response. The patients either continued the second-line drug (n = 142) or received a placebo (n = 143). The endpoint was a flare, defined as recurrence of synovitis. FINDINGS At entry into the study median duration of second-line drug therapy was 5 years (range 2-33). At 52 weeks the cumulative incidence of a flare was 38% for the placebo group and 22% for the continued therapy group (p = 0.002). The risk of a flare was 2.0 times higher for patients receiving placebo than for those continuing the second-line drug (95% CI 1.27 to 3.17). The same trend was found for each second-line drug separately, with the exception of d-penicillamine. Side-effects that necessitated dose reduction or discontinuation occurred in 2 patients in each group. INTERPRETATION Second-line drugs continue to be effective in RA patients who have responded well to initial treatment.
Arthritis Care and Research | 2012
Florence Tubach; Philippe Ravaud; Emilio Martín-Mola; Hassane Awada; Nicholas Bellamy; Claire Bombardier; David T. Felson; Najia Hajjaj-Hassouni; M. Hochberg; Isabelle Logeart; Marco Matucci-Cerinic; M.A.F.J. van de Laar; D. van der Heijde; Maxime Dougados
To estimate the minimum clinically important improvement (MCII) and patient acceptable symptom state (PASS) values for 4 generic outcomes in 5 rheumatic diseases and 7 countries.
Annals of the Rheumatic Diseases | 1998
H.L.M. Brus; M.A.F.J. van de Laar; Erik Taal; Johannes J. Rasker; O. Wiegman
OBJECTIVES To determine the effects of patient education on compliance and on health in patients with active, recent onset rheumatoid arthritis (RA). METHODS A randomised, controlled, assessor blinded, one year trial. The experimental group followed an education programme. All patients started on sulphasalazine therapy. Compliance with sulphasalazine was measured by pill counting. Compliance rates with regimens of physical exercise, endurance activities, and energy conservation were measured by questionnaires. Compliance with prescriptions of joint protection was scored using a test for joint protection performance. Health was measured by a Disease Activity Score (function of erythrocyte sedimentation rate, Ritchie score, and number of swollen joints), C reactive protein, Dutch-AIMS scores, and M-HAQ scores, range of motion of shoulder, elbow, and knee joints. Parameters were scored at baseline and after three, six, and 12 months. RESULTS Sixty of 65 patients gave informed consent, five of them withdrew from follow up. Compliance with sulphasalazine exceeded 80% with no differences between groups. Compliance with physical exercise (at three months), energy conservation (at three and at 12 months), and joint protection (at three months) improved significantly more in the experimental group. The improvements of health were not different in the groups. CONCLUSION Compliance with sulphasalazine among patients with active, recent onset RA is high, whether formal patient education is followed or not. Compliance with physical exercise, energy conservation, and joint protection was increased by patient education. Formal patient education did not improve health status.
Annals of the Rheumatic Diseases | 2007
Wietske Kievit; E.M.M. Adang; Jaap Fransen; H.H. Kuper; M.A.F.J. van de Laar; T.L.Th.A. Jansen; C.M.A. de Gendt; D.R.A.M. de Rooij; H.L.M. Brus; P.C.M. van Oijen; P.L.C.M. van Riel
AIM to evaluate the effects of adalimumab, etanercept and infliximab on disease activity, functional ability and quality of life and the medication costs in a naturalistic design. METHODS All patients from the Dutch Rheumatoid Arthritis Monitoring (DREAM) register starting on tumour necrosis factor (TNF)alpha-blocking agents for the first time were monitored and assessed by trained research nurses every 3 months. The primary outcome was the Disease Activity Score (DAS28) course over the 12 months follow-up, analysed by linear mixed models. Secondary outcomes were the Health Assessment Questionnaire (HAQ), EuroQol five dimensions (EQ-5D) and the Short-Form 36 items (SF36) scores, and medication-related total costs. RESULTS The DAS28 and SF-36 physical component scale decreased in all three medication groups over 12 months, but the decrease was larger for adalimumab and etanercept in comparison to infliximab (p<0.001). The analyses of the HAQ and the EQ-5D scores showed the same (non-significant) trend, namely that at 12 months, the functionality and quality of life was better for adalimumab and etanercept patients. With regard to the medication costs, infliximab treatment resulted in significantly higher costs over the follow-up period than treatments with either adalimumab or etanercept. The comparison between adalimumab and etanercept showed a significant difference in the 12-month DAS28 course (p = 0.031). There were no additional indications for differences in effectiveness or costs between adalimumab and etanercept. CONCLUSION The evaluation of the effectiveness and costs showed that adalimumab and etanercept are more or less equal and favourable compared to infliximab in the first year of treatment.
Annals of the Rheumatic Diseases | 2008
M.K. Reinders; E.N. Van Roon; T.L.Th.A. Jansen; J Delsing; En Griep; M. Hoekstra; M.A.F.J. van de Laar; J.R.B.J. Brouwers
Objectives: To investigate the efficacy and tolerability of allopurinol as the first-choice antihyperuricaemic treatment for gout, and compare the efficacy and tolerability of benzbromarone and probenecid as second-choice treatment. Methods: Prospective, multicentre, open-label, two-stage randomised controlled trial in gout patients with normal renal function. Enrolled patients were given 300 mg allopurinol for 2 months (stage 1). Those patients who could not tolerate allopurinol or who did not attain the target serum urate concentration (sUr) ⩽0.30 mmol/l (5.0 mg/dl), which was defined as successful, were randomised to benzbromarone 200 mg/day or probenecid 2 g/day for another 2 months (stage 2). Results: 96 patients were enrolled in stage 1. 82 patients (85%) were eligible for the analysis at the end of stage 1: there was a mean (SD) decrease in sUr concentration of 35 (11)% from baseline; 20 patients (24%) attained target sUr ⩽0.30 mmol/l; and 9 patients (11%) stopped allopurinol because of adverse drug reactions. 62 patients were enrolled in stage 2. 27 patients received benzbromarone (3 patients not eligible for analysis) and 35 received probenecid (4 patients not eligible for analysis). Treatment with benzbromarone was successful in 22/24 patients (92%) and with probenecid in 20/31 patients (65%) (p = 0.03 compared with benzbromarone). Compared with baseline values, there was a mean (SD) decrease of sUr concentration of 64 (9)% with benzbromarone and 50 (7)% with probenecid (p<0.001). Conclusion: This study showed that allopurinol 300 mg/day has a poor efficacy and tolerability profile when used to attain a biochemical predefined target level of sUr ⩽0.30 mmol/l, following 2 months of treatment. In stage 2, benzbromarone 200 mg/day was more effective and better tolerated than probenecid 2 g/day. Trial registration number: ISRCTN21473387.
Annals of the Rheumatic Diseases | 1992
M.A.F.J. van de Laar; J. K. Van Der Korst
The hypothetically negative influence of food on the clinical activity of seropositive rheumatoid arthritis was studied using two types of artificial elementary food. One diet was allergen free, the other allergen restricted, containing only lactoproteins and yellow dyes. Ninety four patients entered the study, which lasted 12 weeks. During the second four week period they were randomly assigned to one of the two artificial foods. Comparison between baseline and subsequent periods showed only subjective improvements. No differences were seen between the clinical effects of the two tested diets. Nine patients (three in the allergen restricted group, six in the allergen free group) showed favourable responses, followed by marked disease exacerbation during rechallenge. Dietary manipulation also brought about changes in objective disease activity parameters in these patients. The existence of a subgroup of patients in whom food intolerance influences the activity of rheumatoid factor seropositive rheumatoid arthritis deserves serious consideration.
Arthritis Care and Research | 2013
Marloes Vermeer; H.H. Kuper; H J Moens; K. Wiepke Drossaers-Bakker; A.E. van der Bijl; P.L.C.M. van Riel; M.A.F.J. van de Laar
Treat‐to‐target (T2T) leads to improved clinical outcomes in early rheumatoid arthritis (RA). The question is whether these results sustain in the long term. Our objective was to investigate the 3‐year results of a protocolized T2T strategy in daily clinical practice.