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Dive into the research topics where Henk Groen is active.

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Featured researches published by Henk Groen.


Arthritis Research & Therapy | 2011

Baseline predictors of response and discontinuation of tumor necrosis factor-alpha blocking therapy in ankylosing spondylitis: a prospective longitudinal observational cohort study

Suzanne Arends; Elisabeth Brouwer; Eveline van der Veer; Henk Groen; M. K. Leijsma; P. M. Houtman; Tim L. Jansen; Cees G. M. Kallenberg; A. Spoorenberg

IntroductionIdentifying ankylosing spondylitis (AS) patients who are likely to benefit from tumor necrosis factor-alpha (TNF-α) blocking therapy is important, especially in view of the costs and potential side effects of these agents. Recently, the AS Disease Activity Score (ASDAS) has been developed to assess both subjective and objective aspects of AS disease activity. However, data about the predictive value of the ASDAS with respect to clinical response to TNF-α blocking therapy are lacking. The aim of the present study was to identify baseline predictors of response and discontinuation of TNF-α blocking therapy in AS patients in daily clinical practice.MethodsAS outpatients who started TNF-α blocking therapy were included in the Groningen Leeuwarden Ankylosing Spondylitis (GLAS) study, an ongoing prospective longitudinal observational cohort study with follow-up visits according to a fixed protocol. For the present analysis, patients were excluded if they had previously received anti-TNF-α treatment. Predictor analyses of response and treatment discontinuation were performed using logistic and Cox regression models, respectively.ResultsBetween November 2004 and April 2010, 220 patients started treatment with infliximab (n = 32), etanercept (n = 137), or adalimumab (n = 51). At three and six months, 68% and 63% of patients were Assessments in Ankylosing Spondylitis (ASAS)20 responders, 49% and 46% ASAS40 responders, and 49% and 50% Bath Ankylosing Spondylitis Disease Activity Index (BASDAI)50 responders, respectively. Baseline predictors of response were younger age, male gender, higher ASDAS score, higher erythrocyte sedimentation rate (ESR) level, higher C-reactive protein (CRP) level, presence of peripheral arthritis, higher patients global assessment of disease activity, and lower modified Schober test. In August 2010, 64% of patients were still using their TNF-α blocking agent with a median follow-up of 33.1 months (range 2.4 to 68.2). Baseline predictors of discontinuation of TNF-α blocking therapy were female gender, absence of peripheral arthritis, higher BASDAI, lower ESR level, and lower CRP level.ConclusionsBesides younger age and male gender, objective variables such as higher inflammatory markers or ASDAS score were identified as independent baseline predictors of response and/or continuation of TNF-α blocking therapy. In contrast, higher baseline BASDAI score was independently associated with treatment discontinuation. Based on these results, it seems clinically relevant to include more objective variables in the evaluation of anti-TNF-α treatment.


Menopause | 2008

Decreased androgen concentrations and diminished general and sexual well-being in women with premature ovarian failure

Jolande Van Der Stege; Henk Groen; Saskia J. N. van Zadelhoff; Cornelis B. Lambalk; Didi D.M. Braat; Yvonne M. van Kasteren; Evert J. P. van Santbrink; Mirjam J. A. Apperloo; Willibrord C. M. Weijmar Schultz; Annemieke Hoek

Objective: To describe general and sexual well-being in women with premature ovarian failure (POF) and to investigate whether there is a relationship between androgen levels and sexual functioning. Design: Women with POF and healthy volunteers with regular menstrual cycles participated. Participants completed a written questionnaire and underwent hormonal screening. The questionnaire included standardized measures: the Questionnaire for Screening Sexual Dysfunctions, the Shortened Fatigue Questionnaire, and the Symptom Check List-90. Serum hormone measurements included estradiol, total testosterone, bioavailable testosterone, androstenedione, dehydroepiandrosterone, and dehydroepiandrosterone sulfate. Results: Eighty-one women with POF and 68 control women participated in the study. Compared with control women, women with POF reported more complaints of anxiety, depression, somatization, sensitivity, hostility, and psychological distress. Overall women with POF were less satisfied with their sexual life. They had fewer sexual fantasies and masturbated less frequently. Sexual contact was associated with less sexual arousal, reduced lubrication, and increased genital pain. However, the frequency of desire to have sexual contact and the frequency of actual sexual contact with the partner did not differ between women with POF and control women. Women with POF had lower levels of estradiol, total testosterone, and androstenedione. Multiple regression analysis revealed that androgen levels had only a weak influence on sexual functioning; higher total testosterone levels were associated with increased frequency of desire for sexual contact, and higher androstenedione levels were associated with elevated frequency of sexual contact. Conclusions: Women with POF have diminished general and sexual well-being and are less satisfied with their sexual lives than control women. Although women with POF had lower androgen levels, we did not find an important independent role for androgens in various aspects of sexual functioning.


Journal of Gastrointestinal Surgery | 2005

Positron emission tomography with F-18-fluorodeoxyglucose in a combined staging strategy of esophageal cancer prevents unnecessary surgical explorations

Henderik L. van Westreenen; Pierre A.M. Heeren; Hendrik M. van Dullemen; Eric J. van der Jagt; Pieter L. Jager; Henk Groen; John Plukker

Distant metastases or local invasion are frequently found during the explorative phase of surgery for esophageal cancer. This study was performed to determine the rate of patients with incurable disease encountered during exploration and to examine the impact of preoperative staging, including positron emission tomography (PET), on the number of unnecessary explorations. The records of 203 patients with esophageal cancer who were eligible for curative resection were retrospectively reviewed. The surgical reports were analyzed to obtain the reasons for abandoning resection. Furthermore, the different staging modalities according to the related time interval were reviewed for each patient to analyze the influence of them on the number of explorations. After exploratory surgery, resection was abandoned in 78 of the 203 patients (38%) because of distant metastases (n = 59; 29%), metastatic spread and local irresectability (n = 5; 2%), and local irresectability (n = 14; 7%). In a logistic regression model with all preoperative staging modalities and the year of examination as independent variables, F-18-fluorodeoxyglucose (FDG)-PET) was the only modality that predicts intended curative resection in these patients (P < 0.001). In patients with esophageal cancer who are suitable for potentially curative surgery, resection was abandoned mainly because of distant metastases encountered during exploration. The addition of FDG-PET may have reduced the rate of unnecessary surgery in this group of patients.


The New England Journal of Medicine | 2016

Randomized Trial of a Lifestyle Program in Obese Infertile Women

Meike Mutsaerts; Anne M. van Oers; Henk Groen; Jan M. Burggraaff; Walter K. H. Kuchenbecker; Denise A. M. Perquin; Carolien A. M. Koks; Ron van Golde; Eugenie M. Kaaijk; Jaap M. Schierbeek; G.J.E. Oosterhuis; Frank J. Broekmans; Wanda J. E. Bemelmans; Cornelis B. Lambalk; M.F.G. Verberg; Fulco van der Veen; Nicole F. Klijn; Patricia E.A.M. Mercelina; Yvonne M. van Kasteren; Annemiek W. Nap; Egbert A. Brinkhuis; Niels E. A. Vogel; Robert J. A. B. Mulder; Ed T. C. M. Gondrie; Jan Bruin; J. Marko Sikkema; Mathieu H.G. de Greef; Nancy C. W. ter Bogt; Jolande A. Land; Ben Willem J. Mol

BACKGROUND Small lifestyle-intervention studies suggest that modest weight loss increases the chance of conception and may improve perinatal outcomes, but large randomized, controlled trials are lacking. METHODS We randomly assigned infertile women with a body-mass index (the weight in kilograms divided by the square of the height in meters) of 29 or higher to a 6-month lifestyle intervention preceding treatment for infertility or to prompt treatment for infertility. The primary outcome was the vaginal birth of a healthy singleton at term within 24 months after randomization. RESULTS We assigned women who did not conceive naturally to one of two treatment strategies: 290 women were assigned to a 6-month lifestyle-intervention program preceding 18 months of infertility treatment (intervention group) and 287 were assigned to prompt infertility treatment for 24 months (control group). A total of 3 women withdrew consent, so 289 women in the intervention group and 285 women in the control group were included in the analysis. The discontinuation rate in the intervention group was 21.8%. In intention-to-treat analyses, the mean weight loss was 4.4 kg in the intervention group and 1.1 kg in the control group (P<0.001). The primary outcome occurred in 27.1% of the women in the intervention group and 35.2% of those in the control group (rate ratio in the intervention group, 0.77; 95% confidence interval, 0.60 to 0.99). CONCLUSIONS In obese infertile women, a lifestyle intervention preceding infertility treatment, as compared with prompt infertility treatment, did not result in higher rates of a vaginal birth of a healthy singleton at term within 24 months after randomization. (Funded by the Netherlands Organization for Health Research and Development; Netherlands Trial Register number, NTR1530.).


Radiotherapy and Oncology | 2010

A systematic review on the role of FDG-PET/CT in tumour delineation and radiotherapy planning in patients with esophageal cancer

Christina T. Muijs; Jannet C. Beukema; Jan Pruim; Veronique E. Mul; Henk Groen; John Plukker; Johannes A. Langendijk

PURPOSE FDG-PET/CT has proven to be useful in the staging process of esophageal tumours. This review analysed the role of FDG-PET/CT in tumour delineation and radiotherapy planning in comparison with CT alone among patients with esophageal cancer. Thereby we focused on the detection of the primary tumour and lymph nodes by FDG-PET/CT, changes in target volume (TV) delineation based on FDG-PET/CT and its validity, changes in inter- and intra-observer variability in TV delineation, consequences for radiotherapy treatment planning with regard to either target volumes or organs at risk and finally on the validation of FDG-PET/CT-based TVs in terms of treatment outcome. METHODS A literature search was performed in MEDLINE and Cochrane library databases for studies concerning the current value of FDG-PET/CT in tumour detection and delineation and radiotherapy-planning procedures among patients with esophageal cancer. Both prospective and retrospective studies were included. RESULTS Fifty publications met the eligibility criteria, of which 19 were review papers and one was a case report. The remaining 30 publications reported on the results of original studies. FDG-PET was able to identify most primary tumours, with a sensitivity and specificity for the detection of metastatic lymph nodes of 30-93% and 79-100%. The use of FDG-PET/CT resulted in changes of target volumes, and consequently in changes in treatment planning. However, evidence supporting the validity of the use of FDG-PET/CT in the tumour delineation process is very limited. Only three studies reported a significant positive correlation between FDG-PET-based tumour lengths and pathological findings. There were two studies that tested the influence of FDG-PET/CT to the inter- and intra-observer variability. One of them found a significant decrease in inter- and intra-observer variability, while the others did not. Furthermore, there are no studies demonstrating the use of PET/CT in terms of improved locoregional control or survival. CONCLUSION Since the literature is very limited standard implementation of FDG-PET/CT into the tumour delineation process for radiation treatment seems unjustified and needs further clinical validation first.


Journal of Vascular Surgery | 2008

Mortality of ruptured abdominal aortic aneurysm treated with open or endovascular repair

Eric L.G. Verhoeven; Marten R. Kapma; Henk Groen; Ignace F.J. Tielliu; Clark J. Zeebregts; F. Bekkema; Jan J.A.M. van den Dungen

OBJECTIVES The study defined the selection criteria used for treatment of ruptured abdominal aortic aneurysms (RAAAs) and reviewed results during a 5-year period. METHODS From 2002 on, our tertiary referral center adopted a protocol of selective use of endovascular repair for RAAAs. The study included all patients with a proven RAAA who were admitted to our hospital from 2002 to 2006. The primary outcome measure was surgical mortality. RESULTS A total of 187 patients were admitted with an acute AAA, and an RAAA was confirmed 135 (72%) by computed tomography scanning or at laparotomy, and 125 (93%) were treated, 89 by open means and 36 by endovascular means. The overall mortality rate was 24% and the mortality rate was 13.9% for endovascular repair. Endovascular repair was consistently used more often in patients with favorable anatomy and in patients who were hemodynamically more stable. There were considerable differences in approach between the four consultant vascular surgeons. The overall evaluation and inclusion for endovascular treatment increased during the study period. CONCLUSIONS A strict protocol for admission, evaluation, and treatment of RAAA, with selective use of endovascular repair, resulted in low mortality rates in our center.


Seminars in Arthritis and Rheumatism | 1990

Clinical associations of antiribonucleoprotein antibodies in patients with systemic lupus erythematosus

Evert J. ter Borg; Henk Groen; Gerda Horst; Pieter Limburg; Aaktje A. Wouda; Cees G. M. Kallenberg

The authors undertook a cross-sectional study to investigate the clinical associations of antiribonucleoprotein (anti-RNP) antibodies in 49 patients with systemic lupus erythematosus (SLE) without other concomitant connective tissue disorders. The traditional counterimmunoelectrophoresis (CIE) and the immunoblotting (IB) technique were compared. Clinically, special attention was given to the identification of sclerodermalike features. All patients completed a detailed questionnaire, physical examination, and additional investigations including pulmonary function tests, chest roentgenogram, radionuclide transit studies of the esophagus, and nailfold capillary microscopy. Pulmonary function testing and radionuclide transit studies of the esophagus were very sensitive for the detection of (subclinical) pulmonary and esophageal involvement, respectively. Within the relatively homogeneous SLE population, a subset was recognized that was characterized clinically by the presence of sclerodermalike features such as Raynauds phenomenon, sclerodactyly, interstitial changes on chest roentgenogram, and decreased numbers of nailfold capillary loops, and serologically by the presence of anti-RNP antibodies. IB was somewhat more sensitive than CIE for the detection of anti-RNP (anti-Sm/anti-nRNP) antibodies but did not identify other clinical associations. Thus, anti-RNP antibodies in SLE are associated with scleroderma-associated features. For clinical practice, CIE is the technique recommended for their detection.


American Journal of Transplantation | 2012

Cost‐Effectiveness of Hypothermic Machine Preservation Versus Static Cold Storage in Renal Transplantation

Henk Groen; Cyril Moers; Jacqueline M. Smits; Jürgen Treckmann; Diethard Monbaliu; Axel Rahmel; A Paul; Jacques Pirenne; Rutger J. Ploeg; Erik Buskens

Static cold storage (CS) is the most widely used organ preservation method for deceased donor kidney grafts but there is increasing evidence that hypothermic machine perfusion (MP) may result in better outcome after transplantation. We performed an economic evaluation of MP versus CS alongside a multicenter RCT investigating short‐ and long‐term cost‐effectiveness. Three hundred thirty‐six consecutive kidney pairs were included, one of which was assigned to MP and one to CS. The economic evaluation combined the short‐term results based on the empirical data from the study with a Markov model with a 10‐year time horizon. Direct medical costs of hospital stay, dialysis treatment, and complications were included. Data regarding long‐term survival, quality of life, and long‐term costs were derived from literature. The short‐term evaluation showed that MP reduced the risk of delayed graft function and graft failure at lower costs than CS. The Markov model revealed cost savings of


The Lancet Diabetes & Endocrinology | 2014

Effects of sodium restriction and hydrochlorothiazide on RAAS blockade efficacy in diabetic nephropathy: a randomised clinical trial

Arjan J. Kwakernaak; Jan A. Krikken; S. Heleen Binnenmars; Folkert W. Visser; Marc H. Hemmelder; Arend-Jan Woittiez; Henk Groen; Gozewijn D. Laverman; Gerjan Navis

86 750 per life‐year gained in favor of MP. The corresponding incremental cost‐utility ratio was minus


Annals of Surgical Oncology | 2003

Pitfalls of positive findings in staging esophageal cancer with F-18-fluorodeoxyglucose positron emission tomography

Henderik L. van Westreenen; Pierre A.M. Heeren; Pieter L. Jager; Hendrik M. van Dullemen; Henk Groen; John Plukker

496 223 per quality‐adjusted life‐year (QALY) gained. We conclude that life‐years and QALYs can be gained while reducing costs at the same time, when kidneys are preserved by MP instead of CS.

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Annemieke Hoek

University Medical Center Groningen

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Corine M. Koopmans

University Medical Center Groningen

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Jolande A. Land

University Medical Center Groningen

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Maria G. van Pampus

University Medical Center Groningen

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John Plukker

University Medical Center Groningen

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Kim Broekhuijsen

University Medical Center Groningen

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Maureen Franssen

University Medical Center Groningen

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Paul P. van den Berg

University Medical Center Groningen

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