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    <title>Lafeber, F.P.J.G.</title>
    <link>http://repub.eur.nl/res/aut/17889/</link>
    <description>List of Publications</description>
    <language>en</language>
    <image>
      <url>http://repub.eur.nl/static-eur/img/logo.png</url>
      <title>RePub, Erasmus University Rotterdam</title>
      <link>http://repub.eur.nl</link>
    </image>
    <item>
      <title>Skin pentosidine in very early hip/knee osteoarthritis (CHECK) is not a strong independent predictor of radiographic progression over 5 years follow-up (Article)</title>
      <link>http://repub.eur.nl/res/pub/39936/</link>
      <pubDate>2013-04-22T00:00:00Z</pubDate>
      <description>Objectives: Age-related changes in articular cartilage are likely to play a role in the etiology of osteoarthritis (OA). One of the major age-related changes in cartilage is the accumulation of advanced glycation end products (AGEs). The present study evaluates whether pentosidine can predict radiographic progression and/or burden over 5 years follow-up in a cohort of early knee and/or hip OA. Design: The 5 years follow-up data of 300 patients from cohort hip &amp; cohort knee (CHECK) were used. Radiographic progression and burden were assessed by X-rays of both knees and hips (Kellgren and Lawrence (K&amp;L) and Altman scores). Baseline pentosidine levels (and urinary CTXII as a comparator) were measured by high-performance-liquid-chromatography (HPLC) and enzyme linked immunosorbent assay (ELISA). Univariable and multivariable associations including baseline radiographic damage, age, gender, body mass index (BMI) and kidney function were performed. Results: Both pentosidine and urinary C-terminal telopeptide of type II collagen (uCTXII) correlated with radiographic progression and burden. In general pentosidine did not have an added predictive value to uCTXII for progression nor burden of the disease. The best prediction was obtained for burden of radiographic damage (R2= 0.60-0.88), bus this was predominantly determined by baseline radiographic damage (without this parameter R2= 0.07-0.17). Interestingly, pentosidine significantly added to prediction of osteophyte formation, whereas uCTXII significantly added to prediction of JSN in multivariable analysis. Conclusion: Pentosidine adds to prediction of radiographic progression and burden of osteophyte formation and uCTXII to radiographic progression and burden of JSN, but overall skin pentosidine did not perform better that uCTXII in predicting radiographic progression or burden. Burden of damage over 5 years is mainly determined by radiographic joint damage at baseline. </description>
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      <title>Cross-sectional and predictive associations between plasma adipokines and radiographic signs of early-stage knee osteoarthritis: Data from CHECK (Article)</title>
      <link>http://repub.eur.nl/res/pub/37393/</link>
      <pubDate>2012-11-01T00:00:00Z</pubDate>
      <description>Objective: To investigate cross-sectional and predictive associations of plasma adipokines with biochemical markers of systemic joint metabolism and radiographic signs of early-stage knee osteoarthritis (OA). Design: The adipokines pLeptin, pAdiponectin, and pResistin, the cartilage markers C-terminal telopeptide of type II collagen (uCTX-II), N-terminal propeptide of type IIA procollagen (sPIIANP), chondroitin sulfate 846 (sCS846), and cartilage oligomeric matrix protein (sCOMP), and the synovial markers hyaluronic acid (sHA) and N-terminal propeptide of type III procollagen (sPIIINP) were assessed by enzyme-linked immunosorbent assay or radioactive immunoassay in baseline samples of Cohort Hip and Cohort Knee (CHECK), a cohort of 1002 subjects with early-stage symptomatic knee and/or hip OA. Knee radiographs were obtained at baseline and after 2 and 5 years and scored according to Kellgren and Lawrence. Results: pLeptin showed positive associations with uCTX-II, sCOMP, sPIIANP, sHA, and sPIIINP, and with presence and progression of radiographic knee OA. Associations expectedly disappeared after adjustment for body mass index. pResistin showed positive associations with sPIIINP and present and incident radiographic knee OA that were largely independent of BMI. pAdiponectin showed positive associations with uCTX-II and sCOMP. Furthermore, pAdiponectin did not show associations with radiographic knee OA on itself, but associations of pResistin with present radiographic knee OA were stronger in higher pAdiponectin tertiles (P = 0.024 for interaction between pAdiponectin and pResistin). Although statistically significant, all associations were weak. Conclusions: Adipokines may have aggravating, although may be minor, structural effects in early-stage knee OA. </description>
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      <title>Detection of progression of radiographic joint damage in case of very early osteoarthritis: Sensitivity to change of quantitative analysis compared to qualitative grading (Article)</title>
      <link>http://repub.eur.nl/res/pub/39743/</link>
      <pubDate>2012-11-01T00:00:00Z</pubDate>
      <description>For more tailored treatment of osteoarthritis it is worthy to identify different subpopulations early in the disease. Objective of this study is to evaluate whether the sensitivity to detect progression of radiographic features, which may add to this identification, can be improved by quantitative measurement (using Knee Images Digital Analysis; KIDA), compared to qualitative grading (according to the Altman atlas). Among individuals with early signs related to osteoarthritis (Cohort Hip and Cohort Knee, Check) symptomatic knees (n=1082) were selected. Standardized baseline and two-year follow-up radiographs were evaluated for joint space narrowing, osteophyte formation, and bone density changes using KIDA measurement and Altman scales. Sensitivity to change was determined by calculating the standardized response mean (SRM). For all distinct KIDA parameters, the smallest detectable difference was calculated to define radiographic changes at the individual level. The percentage of knees that changed was compared between KIDA measurement and Altman grading. Also agreement between both methods was evaluated. Studying radiographic progression in knees with early signs related to osteoarthritis showed, for all KIDA and Altman parameters, a small SRM and radiographic change in a small percentage of knees. The sensitivity to detect radiographic progression was similar for KIDA measurement and Altman grading. However, agreement between the Altman and KIDA method was limited (kappa ≤0.20). Although sensitivity to change is limited, similar for KIDA measurement and Altman grading, this may not exclude that measurement of separate features might be useful to distinguish subpopulations of osteoarthritis later in the disease. </description>
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      <title>Clusters within a wide spectrum of biochemical markers for osteoarthritis: Data from CHECK, a large cohort of individuals with very early symptomatic osteoarthritis (Article)</title>
      <link>http://repub.eur.nl/res/pub/39324/</link>
      <pubDate>2012-07-01T00:00:00Z</pubDate>
      <description>Objective: To assess a wide spectrum of biochemical markers (biomarkers) in a large cohort of individuals with (very) early symptomatic knee and/or hip osteoarthritis (OA). Secondly, to investigate associations between biomarkers and between biomarkers and demographics to demonstrate validity of the obtained dataset and further investigate the involvement and/or role of these biomarkers in OA. Design: Fourteen biomarkers (uCTX-II, uCTX-I, uNTX-I, sCOMP, sPIIANP, sCS846, sC1,2C, sOC, sPINP, sHA, sPIIINP, pLeptin, pAdiponectin, pResistin) were assessed by ELISA or RIA in CHECK (Cohort Hip and Cohort Knee), a 10-year prospective cohort of 1,002 individuals with early symptomatic knee and/or hip OA. Results: Quality controls revealed that gathered data were technically reliable. The majority of biomarkers showed relevant associations with demographic variables, which were expectedly different between genders and/or menopausal status for some. Principal component analysis enabled identification of five clusters, consecutively designated as 'bone-CTX-II', 'inflammation', 'synovium', 'C1,2C-adipokines', and 'cartilage synthesis' cluster. Notably, uCTX-II clustered with biomarkers of bone metabolism, while sCOMP clustered with biomarkers of synovial activity. Conclusions: The identified clusters extended knowledge on individual biomarkers from mostly smaller studies as did the observed associations between biomarker levels and demographics, from which validity of our data was deduced. uCTX-II may not only reflect articular cartilage but also bone metabolism and sCOMP may reflect synovial rather than cartilage metabolism. Major involvement of adipokines in joint metabolism was not identified. </description>
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      <title>Evaluation of separate quantitative radiographic features adds to the prediction of incident radiographic osteoarthritis in individuals with recent onset of knee pain: 5-year follow-up in the CHECK cohort (Article)</title>
      <link>http://repub.eur.nl/res/pub/39293/</link>
      <pubDate>2012-06-01T00:00:00Z</pubDate>
      <description>Objective: Detailed radiographic evaluation might enable the identification of osteoarthritis (OA) earlier in the disease. This study evaluated whether and which separate quantitative features on knee radiographs of individuals with recent onset knee pain are associated with incidence of radiographic OA and persistence and/or progression of clinical OA during 5-year follow-up. Method: From the Cohort Hip &amp; Cohort Knee study participants with knee pain at baseline were evaluated. Radiographic OA development was defined as Kellgren &amp; Lawrence (K&amp;L) grade ≥II at 5-year follow-up. Clinical OA was defined as persistent knee pain and as progression of Westen Ontario &amp; McMaster Universities Osteoarthritis index (WOMAC) pain and function score during follow-up. At baseline radiographic damage was determined by quantitative measurement of separate features using Knee Images Digital Analysis, and by K&amp;L-grading. Results: Measuring osteophyte area [odds ratio (OR) = 7.0] and minimum joint space width (OR = 0.7), in addition to demographic and clinical characteristics, improved the prediction of radiographic OA 5 years later [area under curve receiver operating characteristic = 0.74 vs 0.64 without radiographic features]. When the predictive score (based on multivariate regression coefficients) was larger than the cut-off for optimal specificity, the chance of incident radiographic OA was 54% instead of the prior probability of 19%. Evaluating separate quantitative features performed slightly better than K&amp;L-grading (AUC = 0.70). Radiographic characteristics hardly added to prediction of clinical OA. Conclusion: In individuals with onset knee pain, radiographic characteristics added to the prediction of radiographic OA development 5 years later. Quantitative radiographic evaluation in individuals with suspected OA is worthwhile when determining treatment strategies and designing clinical trials. </description>
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      <title>Similarities and discrepancies in subchondral bone structure in two differently induced canine models of osteoarthritis (Article)</title>
      <link>http://repub.eur.nl/res/pub/20656/</link>
      <pubDate>2010-07-01T00:00:00Z</pubDate>
      <description>In osteoarthritis (OA), cartilage degradation is accompanied by subchondral bone changes. The pathogenesis and physiology of bone changes in OA are still unclear. The changes in subchondral bone architecture and cartilage damage were compared in differently induced experimental models of OA. Experimental OA was induced bilaterally by anterior cruciate ligament transection (ACLT) or by cartilage trauma (Groove model); bilateral sham surgery served as control. Lysylpyridinoline (LP, bone resorption) and C-telopeptide of type II collagen (CTX-II, cartilage breakdown) were measured over time. At 20 weeks after surgery, the subchondral cortical plate and trabecular bone of the tibia were analyzed by micro-computed tomography (μCT) and cartilage degeneration was analyzed histologically and biochemically. In both models, cartilage degeneration and cortical subchondral plate thinning were present. CTXII levels were elevated over time in both models. Subchondral trabecular bone changes were observed only in the ACLT model, not in the Groove model. Correspondingly, LP levels were elevated over time in the ACLT model and not in the Groove model. Interestingly, the trabecular bone changes in the ACLT model were extended to the metaphyseal area. The early decrease in plate thickness, present in both models, as was cartilage damage, suggests that plate thinning is a phenomenon that is intrinsic to the process of OA independent of the cause/induction of OA. On the other hand, trabecular changes in subchondral and metaphyseal bone are not part of a common pathway of OA development and may be induced biomechanically in the destabilized and less loaded ACLT joint.</description>
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      <title>In early OA, thinning of the subchondral plate is directly related to cartilage damage: results from a canine ACLT-meniscectomy model (Article)</title>
      <link>http://repub.eur.nl/res/pub/20707/</link>
      <pubDate>2010-05-01T00:00:00Z</pubDate>
      <description>Abstract

OBJECTIVE: The pathogenesis of osteoarthritis (OA) includes cartilage degeneration, synovial inflammation, and bone changes. Slowly, the sequence and inter-relationship of these features is becoming clearer. Early models of OA suggest thinning of the subchondral plate in addition to trabecular bone changes. In the present study subchondral bone changes were studied in the canine anterior cruciate ligament transection (ACLT)-meniscectomy model. This model is characterized by intra-joint variability with respect to cartilage damage (predominantly medial) and loading (lateral unloading due to a shifted axis).

METHODS: In 13 Labrador dogs, OA was induced by transection of the anterior cruciate ligament and removal of the medial meniscus. Twelve weeks later, cartilage integrity was evaluated histologically using the modified Mankin score (0-11), and proteoglycan content was determined by Alcian Blue assay. Bone architecture of the tibia was quantified by micro-CT.

RESULTS: Cartilage damage was severe in the medial compartment (Mankin score +3.5, glycosaminoglycan (GAG) content -28%) and mild in the lateral compartment (Mankin score +1.6, GAG content -15%). Thinning and porosity of the subchondral plate were only present on the medial side (-21%, +87%, respectively). Interestingly, changes in trabecular bone structure did almost not occur in the medial compartment (volume fraction -7%) but were clear in the lateral compartment (-20%).

CONCLUSION: Thinning of the subchondral plate is a localized phenomenon related to cartilage degeneration while trabecular bone changes are related to mechanical (un)loading. The different mechanisms responsible for bone changes in OA should be taken in account when designing and interpreting studies interfering with bone turnover in the treatment of OA.</description>
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      <title>CHECK (Cohort Hip and Cohort Knee): Similarities and differences with the Osteoarthritis Initiative (Article)</title>
      <link>http://repub.eur.nl/res/pub/24881/</link>
      <pubDate>2009-09-01T00:00:00Z</pubDate>
      <description>Objective: To describe the osteoarthritis study population of CHECK (Cohort Hip and Cohort Knee) in comparison with relevant selections of the study population of the Osteoarthritis Initiative (OAI) based on clinical status and radiographic parameters. Methods: In The Netherlands a prospective 10-year follow-up study was initiated by the Dutch Arthritis Association on participants with early osteoarthritisrelated complaints of hip and/or knee: CHECK. In parallel in the USA an observational 4-year follow-up study, the OAI, was started by the National Institutes of Health, on patients with or at risk of symptomatic knee osteoarthritis. For comparison with CHECK, the entire cohort and a subgroup of individuals excluding those with exclusively hip pain were compared with relevant subpopulations of the OAI. Results: At baseline, CHECK included 1002 participants with in general similar characteristics as described for the OAI. However, significantly fewer individuals in CHECK had radiographic knee osteoarthritis at baseline when compared with the OAI (p&lt;0.001). In contrast, at baseline, the CHECK cohort reported higher scores on pain, stiffness and functional disability (Western Ontario and McMaster osteoarthritis index) when compared with the OAI (all p&lt;0.001). These differences were supported by physical health status in contrast to mental health (Short Form 36/12) was at baseline significantly worse for the CHECK participants (p&lt;0.001). Conclusion: Although both cohorts focus on the early phase of osteoarthritis, they differ significantly with respect to structural (radiographic) and clinical (health status) characteristics, CHECK expectedly representing participants in an even earlier phase of disease.</description>
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      <title>A role for subchondral bone changes in the process of osteoarthritis; a micro-CT study of two canine models (Article)</title>
      <link>http://repub.eur.nl/res/pub/15160/</link>
      <pubDate>2008-02-01T00:00:00Z</pubDate>
      <description>BACKGROUND: This study evaluates changes in peri-articular bone in two canine models for osteoarthritis: the groove model and the anterior cruciate ligament transection (ACLT) model. METHODS: Evaluation was performed at 10 and 20 weeks post-surgery and in addition a 3-weeks time point was studied for the groove model. Cartilage was analysed, and architecture of the subchondral plate and trabecular bone of epiphyses was quantified using micro-CT. RESULTS: At 10 and 20 weeks cartilage histology and biochemistry demonstrated characteristic features of osteoarthritis in both models (very mild changes at 3 weeks). The groove model presented osteophytes only at 20 weeks, whereas the ACLT model showed osteophytes already at 10 weeks. Trabecular bone changes in the groove model were small and not consistent. This contrasts the ACLT model in which bone volume fraction was clearly reduced at 10 and 20 weeks (15-20%). However, changes in metaphyseal bone indicate unloading in the ACLT model, not in the groove model. For both models the subchondral plate thickness was strongly reduced (25-40%) and plate porosity was strongly increased (25-85%) at all time points studied. CONCLUSION: These findings show differential regulation of subchondral trabecular bone in the groove and ACLT model, with mild changes in the groove model and more severe changes in the ACLT model. In the ACLT model, part of these changes may be explained by unloading of the treated leg. In contrast, subchondral plate thinning and increased porosity were very consistent in both models, independent of loading conditions, indicating that this thinning is an early response in the osteoarthritis process.</description>
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