Background Age- and height-adjusted total kidney volume is currently considered the best prognosticator in patients with autosomal dominant polycystic kidney disease. We tested the ratio of urinary... Show moreBackground Age- and height-adjusted total kidney volume is currently considered the best prognosticator in patients with autosomal dominant polycystic kidney disease. We tested the ratio of urinary epidermal growth factor and monocyte chemotactic peptide 1 for the prediction of the Mayo Clinic Imaging Classes. Methods Urinary epidermal growth factor and monocyte chemotactic peptide 1 levels were measured in two independent cohorts (discovery, n = 74 and validation set, n = 177) and healthy controls (n = 59) by immunological assay. Magnetic resonance imaging parameters were used for total kidney volume calculation and the Mayo Clinic Imaging Classification defined slow (1A-1B) and fast progressors (1C-1E). Microarray and quantitative gene expression analysis were used to test epidermal growth factor and monocyte chemotactic peptide 1 gene expression. Results Baseline ratio of urinary epidermal growth factor and monocyte chemotactic peptide 1 correlated with total kidney volume adjusted for height (r = - 0.6, p < 0.001), estimated glomerular filtration rate (r = 0.69 p < 0.001), discriminated between Mayo Clinic Imaging Classes (p < 0.001), and predicted the variation of estimated glomerular filtration rate at 10 years (r = - 0.51, p < 0.001). Conditional Inference Trees identified cut-off levels of the ratio of urinary epidermal growth factor and monocyte chemotactic peptide 1 for slow and fast progressors at > 132 (100% slow) and < 25.76 (89% and 86% fast, according to age), with 94% sensitivity and 66% specificity (p = 6.51E-16). Further, the ratio of urinary epidermal growth factor and monocyte chemotactic peptide 1 at baseline showed a positive correlation (p = 0.006, r = 0.36) with renal outcome (delta-estimated glomerular filtration rate per year, over a mean follow-up of 4.2 +/- 1.2 years). Changes in the urinary epidermal growth factor and monocyte chemotactic peptide 1 were mirrored by gene expression levels in both human kidney cysts (epidermal growth factor: - 5.6-fold, fdr = 0.001; monocyte chemotactic peptide 1: 3.1-fold, fdr = 0.03) and Pkd1 knock-out mouse kidney (Egf: - 14.8-fold, fdr = 2.37E-20, Mcp1: 2.8-fold, fdr = 6.82E-15). Conclusion The ratio of urinary epidermal growth factor and monocyte chemotactic peptide 1 is a non-invasive pathophysiological biomarker that can be used for clinical risk stratification in autosomal dominant polycystic kidney disease. Show less
Women with breast cancer often wonder whether they should have their other breast removed as well, to prevent a potential tumor from developing there. The exact risks vary significantly per person.... Show moreWomen with breast cancer often wonder whether they should have their other breast removed as well, to prevent a potential tumor from developing there. The exact risks vary significantly per person. We used information about patients, breast cancer characteristics and treatments, and rare and common genetic variant correlated with a higher or lower risk of developing breast cancer in the other breast in large datasets to develop and validate statistical models to predict each patient’s risk of developing a tumor. We investigated whether and how these models might be clinically useful to better inform patients and physicians to tailor clinical decision making about potential strategies to prevent or early detect a tumor in the opposite breast. We discussed statistical aspects about model development and validation, and we provided frameworks about how to develop and assess prediction performance of risk prediction models using motivating examples in breast cancer. Show less
The main objective of work presented in this thesis was to explore the clinical utility of the Polygenic Risk Score (PRS) based on breast cancer associated common low risk variants, which explain ... Show moreThe main objective of work presented in this thesis was to explore the clinical utility of the Polygenic Risk Score (PRS) based on breast cancer associated common low risk variants, which explain ~18% of the familial relative risk, for individual breast cancer risk prediction. It did so by generating knowledge about the PRS in the Dutch general population and in clinic-based breast cancer families, as well as in a large international population of BRCA1/2 pathogenic variant carriers. We have validated the association of the PRS with breast cancer for women in both the Dutch population and breast cancer families and showed a better risk-discrimination by adding the PRS to family-based risk prediction. Secondly, we have shown that addition of the PRS to family-based risk prediction has an impact on screening recommendations for many non-carriers and carriers of a pathogenic variant in a moderate breast cancer gene. The results will support implementation of comprehensive risk prediction in the clinic, and may help women to make more informed choices about their optimal clinical management. Show less
Background The Framingham hypertension risk score is a well-known and simple model for predicting hypertension in adults. In the current study, we aimed to assess the predictive ability of this... Show moreBackground The Framingham hypertension risk score is a well-known and simple model for predicting hypertension in adults. In the current study, we aimed to assess the predictive ability of this model in a Middle Eastern population.MethodsWe studied 5423 participants, aged 20-69years, without hypertension, who participated in two consecutive examination cycles of the Tehran Lipid and Glucose Study (TLGS). We assessed discrimination based on Harrell's concordance statistic (c-index) and calibration (graphical comparison of predicted vs. observed). We evaluated the original, recalibrated (for intercept and slope), and revised (for beta coefficients) models.ResultsOver the 3-year follow-up period, 319 participants developed hypertension. The Framingham hypertension risk score performed well in discriminating between individuals who developed hypertension and those who did not (c-index=0.81, 95% CI: 0.79-0.83). Initially, there was a systematic underestimation of the original risk score (events predicted), which was readily corrected by a simple model revision.ConclusionsThe revised Framingham hypertension risk score can be used as a screening tool in public health and clinical practice to facilitate the targeting of preventive interventions in high-risk Middle Eastern people. Show less
Background The multi-biomarker disease activity (MBDA) test measures 12 serum protein biomarkers to quantify disease activity in RA patients. A newer version of the MBDA score, adjusted for age,... Show moreBackground The multi-biomarker disease activity (MBDA) test measures 12 serum protein biomarkers to quantify disease activity in RA patients. A newer version of the MBDA score, adjusted for age, sex, and adiposity, has been validated in two cohorts (OPERA and BRASS) for predicting risk for radiographic progression. We now extend these findings with additional cohorts to further validate the adjusted MBDA score as a predictor of radiographic progression risk and compare its performance with that of other risk factors.MethodsFour cohorts were analyzed: the BRASS and Leiden registries and the OPERA and SWEFOT studies (total N =953). Treatments included conventional DMARDs and anti-TNFs. Associations of radiographic progression (Delta TSS) per year with the adjusted MBDA score, seropositivity, and clinical measures were evaluated using linear and logistic regression. The adjusted MBDA score was (1) validated in Leiden and SWEFOT, (2) compared with other measures in all four cohorts, and (3) used to generate curves for predicting risk of radiographic progression.ResultsUnivariable and bivariable analyses validated the adjusted MBDA score and found it to be the strongest, independent predicator of radiographic progression (Delta TSS >5) compared with seropositivity (rheumatoid factor and/or anti-CCP), baseline TSS, DAS28-CRP, CRP SJC, or CDAI. Neither DAS28-CRP, CDAI, SJC, nor CRP added significant information to the adjusted MBDA score as a predictor, and the frequency of radiographic progression agreed with the adjusted MBDA score when it was discordant with these measures. The rate of progression (Delta TSS >5) increased from <2% in the low (1-29) adjusted MBDA category to 16% in the high (45-100) category. A modeled risk curve indicated that risk increased continuously, exceeding 40% for the highest adjusted MBDA scores.ConclusionThe adjusted MBDA score was validated as an RA disease activity measure that is prognostic for radiographic progression. The adjusted MBDA score was a stronger predictor of radiographic progression than conventional risk factors, including seropositivity, and its prognostic ability was not significantly improved by the addition of DAS28-CRP, CRP, SJC, or CDAI. Show less
Aalst, C.M. van der; Denissen, S.J.A.M.; Vonder, M.; Gratama, J.W.C.; Adriaansen, H.J.; Kuijpers, D.; ... ; Koning, H.J. de 2020
Aim Screening for a high cardiovascular disease (CVD) risk followed by preventive treatment can potentially reduce coronary heart disease-related morbidity and mortality. ROBINSCA (Risk Or Benefit... Show moreAim Screening for a high cardiovascular disease (CVD) risk followed by preventive treatment can potentially reduce coronary heart disease-related morbidity and mortality. ROBINSCA (Risk Or Benefit IN Screening for CArdiovascular disease) is a population-based randomized controlled screening trial that investigates the effectiveness of CVD screening in asymptomatic participants using the Systematic COronary Risk Evaluation (SCORE) model or coronary artery calcium (CAC) scoring. This study describes the distributions in risk and treatment in the ROBINSCA trial.Methods and results Individuals at expected elevated CVD risk were randomized into screening arm A (n = 14 478; SCORE, 10-year fatal and non-fatal risk); or screening arm B (n= 14 450; CAC scoring). Preventive treatment was largely advised according to current Dutch guidelines. Risk and treatment differences between the screening arms were analysed. A total of 12 185 participants (84.2%) in arm A and 12 950 (89.6%) in arm B were screened. In total, 48.7% were women, and median age was 62 (interquartile range 10) years. SCORE screening identified 45.1% at low risk (SCORE < 10%), 26.5% at intermediate risk (SCORE 10-20%), and 28.4% at high risk (SCORE >= 20%). According to CAC screening, 76.0% were at low risk (Agatston < 100), 15.1% at high risk (Agatston 100-399), and 8.9% at very high risk (Agatston >= 400). CAC scoring significantly reduced the number of individuals indicated for preventive treatment compared to SCORE (relative reduction women: 37.2%; men: 28.8%).Conclusion We showed that compared to risk stratification based on SCORE, CAC scoring classified significantly fewer men and women at increased risk, and less preventive treatment was indicated. Show less
Stalenhoef voerde een een gerandomiseerd onderzoek uit op de Spoedeisende Hulp-afdelingen van het LUMC en geaffilieerde ziekenhuizen onder leiding van prof. Jaap van Dissel (Infectieziekten), over... Show moreStalenhoef voerde een een gerandomiseerd onderzoek uit op de Spoedeisende Hulp-afdelingen van het LUMC en geaffilieerde ziekenhuizen onder leiding van prof. Jaap van Dissel (Infectieziekten), over de toepassing van een klinische beslisregel om het risico in te schatten bij patiënten die zich presenteren met pyelonefritis, acute prostatitis of urosepsis.Het onderzoek waaraan 370 patiënten deelnamen, toonde aan dat het aantal ziekenhuisopnames met de toepassing van deze beslisregel significant werd verlaagd. Het aantal thuis behandelde patiënten dat op een later moment toch werd opgenomen, was hierbij hoger dan verwacht. Dit kwam mede doordat er bij een aantal patiënten toch een andere diagnose werd gesteld op het moment dat de kweekuitslagen bekend werden. Verder onderzoek richt zich op verbetering van de beslisregel door deze te combineren met een biomarker die de acute immuunrespons reflecteert. Show less
RA is a chronic and progressive autoimmune disease affecting approximately 1% of the population worldwide, and has a large risk for causing disability of patients and consequently high costs in... Show moreRA is a chronic and progressive autoimmune disease affecting approximately 1% of the population worldwide, and has a large risk for causing disability of patients and consequently high costs in health care if left un- or improperly treated. To prevent this, patients with RA need to be identified as early as possible and treated adequately to prevent worse outcome. Early recognition, together with prediction of the disease outcome at the individual patient level would allow to achieve personalized medicine. The main scope of this thesis was to identify and evaluate the quality of risk factors for their usefulness in predicting disease course and outcome of RA. To this end, characteristics and disease outcome of RA patients included in the Leiden EAC were studied. Show less
The aim of this thesis was to study cardiovascular risk management in old age, in order to facilitate the development of age specific guidelines. In part one the current status of cardiovascular... Show moreThe aim of this thesis was to study cardiovascular risk management in old age, in order to facilitate the development of age specific guidelines. In part one the current status of cardiovascular prevention in old age is described, including a study into general practitioners__ attitudes and perceived barriers in this respect. The second part explores the incremental value of routine-ECGs for cardiovascular risk management in older persons from the general population, beyond existing information from medical records. The third part focuses on primary prevention, exploring the performance of classic risk factors, and some new biomarkers, in predicting cardiovascular mortality in very old people from the general population. It was concluded that a homocysteine level alone accurately identifies those at high risk of cardiovascular mortality, whereas classic risk factors included in the Framingham risk score do not. Next, in various age strata from age 55 years onwards, the association between blood pressure and mortality was studied. Finally, a systematic review into the diagnostic accuracy of natriuretic peptides for the diagnosis of chronic heart failure in older persons from the general population was performed, followed by a study in a cohort of nonagenarians into the prognostic value of NT-proBNP. A general discussion is provided, including directions for future research. Show less