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Dive into the research topics where M E van Leerdam is active.

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Featured researches published by M E van Leerdam.


The American Journal of Gastroenterology | 2003

Acute upper GI bleeding: did anything change?: Time trend analysis of incidence and outcome of acute upper GI bleeding between 1993/1994 and 2000

M E van Leerdam; E M Vreeburg; E. A. J. Rauws; A. A.M. Geraedts; Jan G.P. Tijssen; Johannes B. Reitsma; G. N. J. Tytgat

OBJECTIVES:The aim of this study was to examine recent time trends in incidence and outcome of upper GI bleeding.METHODS:Prospective data collection on all patients presenting with acute upper GI bleeding from a defined geographical area in the period 1993/1994 and 2000.RESULTS:Incidence decreased from 61.7/100,000 in 1993/94 to 47.7/100,000 persons annually in 2000, corresponding to a 23% decrease in incidence after age adjustment (95% CI = 15–30%). The incidence was higher among patients of more advanced age. Rebleeding (16% vs 15%) and mortality (14% vs 13%) did not differ between the two time periods. Ulcer bleeding was the most frequent cause of bleeding, at 40% (1993/94) and 46% (2000). Incidence remained stable for both duodenal and gastric ulcer bleeding. Almost one half of all patients with peptic ulcer bleeding were using nonsteroidal anti-inflammatory drugs or aspirin. Also, among patients with ulcer bleeding, rebleeding (22% vs 20%) and mortality (15% vs 14%) did not differ between the two time periods. Increasing age, presence of severe and life-threatening comorbidity, and rebleeding were associated with higher mortality.CONCLUSIONS:Between 1993/1994 and 2000, among patients with acute upper GI bleeding, the incidence rate of upper GI bleeding significantly decreased, but no improvement was seen in the risk of rebleeding or mortality in these patients. The incidence rate of ulcer bleeding remained stable. Prevention of ulcer bleeding is important.


Gut | 2010

Screening for colorectal cancer: randomised trial comparing guaiac-based and immunochemical faecal occult blood testing and flexible sigmoidoscopy

Lieke Hol; M E van Leerdam; M. van Ballegooijen; A J van Vuuren; H. van Dekken; Jacqueline C. Reijerink; A C M van der Togt; J. D. F. Habbema; E. J. Kuipers

Background: Screening for colorectal cancer (CRC) is widely accepted, but there is no consensus on the preferred strategy. We conducted a randomised trial comparing participation and detection rates (DR) per screenee of guaiac-based faecal occult blood test (gFOBT), immunochemical FOBT (FIT), and flexible sigmoidoscopy (FS) for CRC screening. Methods: A representative sample of the Dutch population (n = 15 011), aged 50–74 years, was 1:1:1 randomised prior to invitation to one of the three screening strategies. Colonoscopy was indicated for screenees with a positive gFOBT or FIT, and for those in whom FS revealed a polyp with a diameter ⩾10 mm; adenoma with ⩾25% villous component or high grade dysplasia; serrated adenoma; ⩾3 adenomas; ⩾20 hyperplastic polyps; or CRC. Results: The participation rate was 49.5% (95% confidence interval (CI) 48.1 to 50.9%) for gFOBT, 61.5% (CI, 60.1 to 62.9%) for FIT and 32.4% (CI, 31.1 to 33.7%) for FS screening. gFOBT was positive in 2.8%, FIT in 4.8% and FS in 10.2%. The DR of advanced neoplasia was significantly higher in the FIT (2.4%; OR, 2.0; CI, 1.3 to 3.1) and the FS arm (8.0%; OR, 7.0; CI, 4.6 to 10.7) than the gFOBT arm (1.1%). FS demonstrated a higher diagnostic yield of advanced neoplasia per 100 invitees (2.4; CI, 2.0 to 2.8) than gFOBT (0.6; CI, 0.4 to 0.8) or FIT (1.5; CI, 1.2 to 1.9) screening. Conclusion: This randomised population-based CRC-screening trial demonstrated superior participation and detection rates for FIT compared to gFOBT screening. FIT screening should therefore be strongly preferred over gFOBT screening. FS screening demonstrated a higher diagnostic yield per 100 invitees than both FOBTs.


The American Journal of Gastroenterology | 2010

High Cancer Risk in Peutz–Jeghers Syndrome: A Systematic Review and Surveillance Recommendations

M G F van Lier; Anja Wagner; Elisabeth M. H. Mathus-Vliegen; Ernst J. Kuipers; Ewout W. Steyerberg; M E van Leerdam

OBJECTIVES:Peutz–Jeghers syndrome (PJS) is an autosomal dominant inherited disorder associated with increased cancer risk. Surveillance and patient management are, however, hampered by a wide range in cancer risk estimates. We therefore performed a systematic review to assess cancer risks in PJS patients and used these data to develop a surveillance recommendation.METHODS:A systematic PubMed search was performed up to February 2009, and all original articles dealing with PJS patients with confirmed cancer diagnoses were included. Data involving cancer frequencies, mean ages at cancer diagnosis, relative risks (RRs), and cumulative risks were collected.RESULTS:Twenty-one original articles, 20 cohort studies, and one meta-analysis fulfilled the inclusion criteria. The cohort studies showed some overlap in the patient population and included a total of 1,644 patients; 349 of them developed 384 malignancies at an average age of 42 years. The most common malignancy was colorectal cancer, followed by breast, small bowel, gastric, and pancreatic cancers. The reported lifetime risk for any cancer varied between 37 and 93%, with RRs ranging from 9.9 to 18 in comparison with the general population. Age-related cumulative risks were given for any cancer and gastrointestinal, gynecological, colorectal, pancreatic, and lung cancers.CONCLUSIONS:PJS patients are markedly at risk for several malignancies, in particular gastrointestinal cancers and breast cancer. On the basis of these elevated risks, a surveillance recommendation is developed to detect malignancies in an early phase and to remove polyps that may be premalignant and may cause complications, so as to improve the outcome.


British Journal of Cancer | 2009

Screening for colorectal cancer: random comparison of guaiac and immunochemical faecal occult blood testing at different cut-off levels

Lieke Hol; Janneke Wilschut; M. van Ballegooijen; A J van Vuuren; H van der Valk; Jacqueline C. Reijerink; A C M van der Togt; E. J. Kuipers; J. D. F. Habbema; M E van Leerdam

Immunochemical faecal occult blood testing (FIT) provides quantitative test results, which allows optimisation of the cut-off value for follow-up colonoscopy. We conducted a randomised population-based trial to determine test characteristics of FIT (OC-Sensor micro, Eiken, Japan) screening at different cut-off levels and compare these with guaiac-based faecal occult blood test (gFOBT) screening in an average risk population. A representative sample of the Dutch population (n=10 011), aged 50–74 years, was 1 : 1 randomised before invitation to gFOBT and FIT screening. Colonoscopy was offered to screenees with a positive gFOBT or FIT (cut-off 50 ng haemoglobin/ml). When varying the cut-off level between 50 and 200 ng ml−1, the positivity rate of FIT ranged between 8.1% (95% CI: 7.2–9.1%) and 3.5% (95% CI: 2.9–4.2%), the detection rate of advanced neoplasia ranged between 3.2% (95% CI: 2.6–3.9%) and 2.1% (95% CI: 1.6–2.6%), and the specificity ranged between 95.5% (95% CI: 94.5–96.3%) and 98.8% (95% CI: 98.4–99.0%). At a cut-off value of 75 ng ml−1, the detection rate was two times higher than with gFOBT screening (gFOBT: 1.2%; FIT: 2.5%; P<0.001), whereas the number needed to scope (NNscope) to find one screenee with advanced neoplasia was similar (2.2 vs 1.9; P=0.69). Immunochemical faecal occult blood testing is considerably more effective than gFOBT screening within the range of tested cut-off values. From our experience, a cut-off value of 75 ng ml−1 provided an adequate positivity rate and an acceptable trade-off between detection rate and NNscope.


Best Practice & Research in Clinical Gastroenterology | 2008

Epidemiology of acute upper gastrointestinal bleeding

M E van Leerdam

Acute upper gastrointestinal bleeding is an important emergency situation. Population-based epidemiology data are important to get insight in the actual healthcare problem. There are only few recent epidemiological surveys regarding acute upper gastrointestinal bleeding. Several surveys focusing on peptic ulcer disease showed a significant decrease in admission and mortality of peptic ulcer disease. Several more recent epidemiological surveys show a decrease in incidence of all cause upper gastrointestinal bleeding. The incidence of peptic ulcer bleeding remained stable. Peptic ulcer bleeding is the most common cause of upper gastrointestinal bleeding, responsible for about 50% of all cases, followed by oesophagitis and erosive disease. Variceal bleeding is the cause of bleeding in cirrhotic patients in 50-60%. Rebleeding in upper gastrointestinal bleeding occurs in 7-16%, despite endoscopic therapy. Rebleeding is especially high in variceal bleeding and peptic ulcer bleeding. Mortality ranges between 3 and 14% and did not change in the past 10 years. Mortality is increasing with increasing age and is significantly higher in patients who are already admitted in hospital for co-morbidity. Risk factors for peptic ulcer bleeding are NSAIDs use and H. pylori infection. In patients at risk for gastrointestinal bleeding and using NSAIDs, a protective drug was only used in 10%. COX-2 selective inhibitors do cause less gastroduodenal ulcers compared to non-selective NSAIDs, however, more cardiovascular adverse events are reported. H. pylori infection is found in about 50% of peptic ulcer bleeding patients. H. pylori should be tested for in all ulcer patients and eradication should be given.


The American Journal of Gastroenterology | 2012

Immunochemical Fecal Occult Blood Testing Is Equally Sensitive for Proximal and Distal Advanced Neoplasia

T. R. de Wijkerslooth; Esther M. Stoop; Patrick N M Bossuyt; G. A. Meijer; M. van Ballegooijen; A.H.C. van Roon; Inge Stegeman; Roderik A. Kraaijenhagen; P. Fockens; M E van Leerdam; Evelien Dekker; E. J. Kuipers

OBJECTIVE:Fecal immunochemical testing (FIT) is increasingly used for colorectal cancer (CRC) screening. We aimed to estimate its diagnostic accuracy in invitational population screening measured against colonoscopy.METHODS:Participants (50–75 years) in an invitational primary colonoscopy screening program were asked to complete one sample FIT before colonoscopy. We estimated FIT sensitivity, specificity, and predictive values in detecting CRC and advanced neoplasia (carcinomas and advanced adenomas) for cutoff levels of 50 (FIT50), 75 (FIT75), and 100 (FIT100) ng hemoglobin (Hb)/ml, corresponding with, respectively, 10, 15 and 20 μg Hb/g feces.RESULTS:A total of 1,256 participants underwent a FIT and screening colonoscopy. Advanced neoplasia was detected by colonoscopy in 119 (9%), 8 (0.6%) of them had CRC. At FIT50, 121 (10%) had a positive test result; 45 (37%) had advanced neoplasia and 7 (6%) had CRC. A total of 74 of 1,135 FIT50 negatives (7%) had advanced neoplasia including 1 (0.1%) CRC. FIT50 had a sensitivity of 38% (95% confidence interval (CI): 29–47) for advanced neoplasia and 88% (95% CI: 37–99) for CRC at a specificity of 93% (95% CI: 92–95) and 91% (95% CI: 89–92), respectively. The positive and negative predictive values for FIT50 were 6% (95% CI: 3–12) and almost 100% (95% CI: 99–100) for CRC, and 37% (95% CI: 29–46) and 93% (95% CI: 92–95) for advanced neoplasia. The sensitivity and specificity of FIT75 for advanced neoplasia were 33% (95% CI: 25–42) and 96% (95% CI: 94–97). At FIT100, 71 screenees (6%) had a positive test result. The sensitivity and specificity of FIT100 were for advanced neoplasia 31% (95% CI: 23–40) and 97% (95% CI: 96–98), and for CRC 75% (95% CI: 36–96) and 95% (95% CI: 93–96). The area under curve for detecting advanced neoplasia was 0.70 (95% CI: 0.64–0.76). FIT had a similar sensitivity for proximal and distal advanced neoplasia at cutoffs of 50 (38% vs. 37%; P=0.99), 75 (33% vs. 31%; P=0.85) and 100 (33% vs. 29%; P=0.68) ng Hb/ml.DISCUSSION:Nine out of ten screening participants with CRC and four out of ten with advanced neoplasia will be detected using one single FIT at low cutoff. Sensitivity in detecting proximal and distal advanced neoplasia is comparable.


Endoscopy | 2012

The NordICC Study: rationale and design of a randomized trial on colonoscopy screening for colorectal cancer.

M. F. Kaminski; Michael Bretthauer; Ann G. Zauber; E. J. Kuipers; Hans-Olov Adami; M. van Ballegooijen; Jaroslaw Regula; M E van Leerdam; T. Stefansson; Lars Påhlman; Evelien Dekker; Miguel A. Hernán; Kjetil Garborg; Geir Hoff

BACKGROUND AND STUDY AIM While colonoscopy screening is widely used in several European countries and the United States, there are no randomized trials to quantify its benefits. The Nordic-European Initiative on Colorectal Cancer (NordICC) is a multinational, randomized controlled trial aiming at investigating the effect of colonoscopy screening on colorectal cancer (CRC) incidence and mortality. This paper describes the rationale and design of the NordICC trial. STUDY DESIGN Men and women aged 55 to 64 years are drawn from the population registries in the participating countries and randomly assigned to either once-only colonoscopy screening with removal of all detected lesions, or no screening (standard of care in the trial regions). All individuals are followed for 15 years after inclusion using dedicated national registries. The primary end points of the trial are cumulative CRC-specific death and CRC incidence during 15 years of follow-up. POWER ANALYSIS: We hypothesize a 50 % CRC mortality-reducing efficacy of the colonoscopy intervention and predict 50 % compliance, yielding a 25 % mortality reduction among those invited to screening. For 90 % power and a two-sided alpha level of 0.05, using a 2:1 randomization, 45 600 individuals will be randomized to control, and 22 800 individuals to the colonoscopy group. Interim analyses of the effect of colonoscopy on CRC incidence and mortality will be performed at 10-year follow-up. CONCLUSIONS The aim of the NordICC trial is to quantify the effectiveness of population-based colonoscopy screening. This will allow development of evidence-based guidelines for CRC screening in the general population.


The American Journal of Gastroenterology | 2011

High cumulative risk of intussusception in patients with Peutz-Jeghers syndrome: time to update surveillance guidelines?

M G F van Lier; Elisabeth M. H. Mathus-Vliegen; Anja Wagner; M E van Leerdam; E. J. Kuipers

OBJECTIVES:Peutz–Jeghers syndrome (PJS) is characterized by gastrointestinal hamartomas. The hamartomas are located predominantly in the small intestine and may cause intussusceptions. We aimed to assess the characteristics, risk, and onset of intussusception in a large cohort of PJS patients to determine whether enteroscopy with polypectomy should be incorporated into surveillance recommendations.METHODS:All PJS patients from two academic hospitals were included in this cohort study (prospective follow-up between 1995 and July 2009). We obtained clinical data by interview and chart review. Deceased family members with PJS were included retrospectively. Cumulative intussusception risks were calculated by Kaplan–Meier analysis.RESULTS:We included 110 PJS patients (46% males) from 50 families. In all, 76 patients (69%) experienced at least one intussusception (range 1–6), at a median age of 16 (3–50) years at first occurrence. The intussusception risk was 50% at the age of 20 years (95% confidence interval 17–23 years) and the risk was independent of sex, family history, and mutation status. The intussusceptions occurred in the small intestine in 95% of events, and 80% of all intussusceptions (n=128) presented as an acute abdomen. Therapy was surgical in 92.5% of events. Based on 37 histology reports, the intussusceptions were caused by polyps with a median size of 35 mm (range 15–60 mm).CONCLUSIONS:PJS patients carry a high cumulative intussusception risk at young age. Intussusceptions are generally caused by polyps >15 mm and treatment is mostly surgical. These results support the approach of enteroscopic surveillance, with removal of small-intestinal polyps >10–15 mm to prevent intussusceptions. The effect of such an approach on the incidence of intussusception remains to be established in prospective trials.


Gut | 2016

Development and validation of the WASP classification system for optical diagnosis of adenomas, hyperplastic polyps and sessile serrated adenomas/polyps

J E G IJspeert; B.A. Bastiaansen; M E van Leerdam; Gerrit A. Meijer; S. van Eeden; Silvia Sanduleanu; Erik J. Schoon; Tanya M. Bisseling; Manon Spaander; N van Lelyveld; M. Bargeman; Junfeng Wang; Evelien Dekker

Objective Accurate endoscopic differentiation would enable to resect and discard small and diminutive colonic lesions, thereby increasing cost-efficiency. Current classification systems based on narrow band imaging (NBI), however, do not include neoplastic sessile serrated adenomas/polyps (SSA/Ps). We aimed to develop and validate a new classification system for endoscopic differentiation of adenomas, hyperplastic polyps and SSA/Ps <10 mm. Design We developed the Workgroup serrAted polypS and Polyposis (WASP) classification, combining the NBI International Colorectal Endoscopic classification and criteria for differentiation of SSA/Ps in a stepwise approach. Ten consultant gastroenterologists predicted polyp histology, including levels of confidence, based on the endoscopic aspect of 45 polyps, before and after participation in training in the WASP classification. After 6 months, the same endoscopists predicted polyp histology of a new set of 50 polyps, with a ratio of lesions comparable to daily practice. Results The accuracy of optical diagnosis was 0.63 (95% CI 0.54 to 0.71) at baseline, which improved to 0.79 (95% CI 0.72 to 0.86, p<0.001) after training. For polyps diagnosed with high confidence the accuracy was 0.73 (95% CI 0.64 to 0.82), which improved to 0.87 (95% CI 0.80 to 0.95, p<0.01). The accuracy of optical diagnosis after 6 months was 0.76 (95% CI 0.72 to 0.80), increasing to 0.84 (95% CI 0.81 to 0.88) considering high confidence diagnosis. The combined negative predictive value with high confidence of diminutive neoplastic lesions (adenomas and SSA/Ps together) was 0.91 (95% CI 0.83 to 0.96). Conclusions We developed and validated the first integrative classification method for endoscopic differentiation of small and diminutive adenomas, hyperplastic polyps and SSA/Ps. In a still image evaluation setting, introduction of the WASP classification significantly improved the accuracy of optical diagnosis overall as well as SSA/P in particular, which proved to be sustainable after 6 months.


British Journal of Cancer | 2010

Preferences for colorectal cancer screening strategies: a discrete choice experiment

Lieke Hol; E de Bekker-Grob; L. van Dam; Bas Donkers; E. J. Kuipers; J. D. F. Habbema; Ewout W. Steyerberg; M E van Leerdam; Marie-Louise Essink-Bot

Background:Guidelines underline the role of individual preferences in the selection of a screening test, as insufficient evidence is available to recommend one screening test over another. We conducted a study to determine the preferences of individuals and to predict uptake for colorectal cancer (CRC) screening programmes using various screening tests.Methods:A discrete choice experiment (DCE) questionnaire was distributed among naive subjects, yet to be screened, and previously screened subjects, aged 50–75 years. Subjects were asked to choose between scenarios on the basis of faecal occult blood test (FOBT), flexible sigmoidoscopy (FS), total colonoscopy (TC) with various test-specific screening intervals and mortality reductions, and no screening (opt-out).Results:In total, 489 out of 1498 (33%) screening-naïve subjects (52% male; mean age±s.d. 61±7 years) and 545 out of 769 (71%) previously screened subjects (52% male; mean age±s.d. 61±6 years) returned the questionnaire. The type of screening test, screening interval, and risk reduction of CRC-related mortality influenced subjects’ preferences (all P<0.05). Screening-naive and previously screened subjects equally preferred 5-yearly FS and 10-yearly TC (P=0.24; P=0.11), but favoured both strategies to annual FOBT screening (all P-values <0.001) if, based on the literature, realistic risk reduction of CRC-related mortality was applied. Screening-naive and previously screened subjects were willing to undergo a 10-yearly TC instead of a 5-yearly FS to obtain an additional risk reduction of CRC-related mortality of 45% (P<0.001).Conclusion:These data provide insight into the extent by which interval and risk reduction of CRC-related mortality affect preferences for CRC screening tests. Assuming realistic test characteristics, subjects in the target population preferred endoscopic screening over FOBT screening, partly, due to the more favourable risk reduction of CRC-related mortality by endoscopy screening. Increasing the knowledge of potential screenees regarding risk reduction by different screening strategies is, therefore, warranted to prevent unrealistic expectations and to optimise informed choice.

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Dive into the M E van Leerdam's collaboration.

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E. J. Kuipers

Erasmus University Rotterdam

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M. van Ballegooijen

Erasmus University Rotterdam

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Anja Wagner

Erasmus University Rotterdam

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J. D. F. Habbema

Erasmus University Rotterdam

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Ewout W. Steyerberg

Erasmus University Rotterdam

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Lieke Hol

Erasmus University Rotterdam

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Ernst J. Kuipers

Erasmus University Medical Center

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Arend G. J. Aalbers

Netherlands Cancer Institute

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Dewkoemar Ramsoekh

Erasmus University Rotterdam

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