R de Vries

Ziekenhuis Tjongerschans, Heerenveen, Friesland, Netherlands

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Publications (83)276.54 Total impact

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    ABSTRACT: Reduced nitric oxide (NO)/cGMP signalling is observed in age-related vascular disease. We hypothesize that this disturbed signalling involves effects of genomic instability, a primary causal factor in aging, on vascular smooth muscle cells (VSMCs) and that the underlying mechanism plays a role in human age-related vascular disease. To test our hypothesis, we combined experiments in mice with genomic instability resulting from the defective nucleotide excision repair gene ERCC1 (Ercc1d/- mice), human VSMC cultures and population genome-wide association studies (GWAS). Aortic rings of Ercc1d/- mice showed 43% reduced responses to the soluble guanylate cyclase (sGC) stimulator sodium nitroprusside (SNP). Inhibition of phosphodiesterase (PDE) 1 and 5 normalized SNP-relaxing effects in Ercc1d/- to wild-type (WT) levels. PDE1C levels were increased in lung and aorta. cGMP hydrolysis by PDE in lungs was higher in Ercc1d/- mice. No differences in activity or levels of cGMP-dependent protein kinase 1 or sGC were observed in Ercc1d/- mice compared with WT. Senescent human VSMC showed elevated PDE1A and PDE1C and PDE5 mRNA levels (11.6-, 9-and 2.3-fold respectively), which associated with markers of cellular senescence. Conversely, PDE1 inhibition lowered expression of these markers. Human genetic studies revealed significant associations of PDE1A single nucleotide polymorphisms with diastolic blood pressure (DBP; β =0.28, P=2.47×10-5) and carotid intima-media thickness (cIMT; β =-0.0061, P=2.89×10-5). In summary, these results show that genomic instability and cellular senescence in VSMCs increase PDE1 expression. This might play a role in aging-related loss of vasodilator function, VSMC senescence, increased blood pressure and vascular hypertrophy.
    No preview · Article · Oct 2015 · Clinical Science
  • Article: PP.14.07

    No preview · Article · Jun 2015 · Journal of Hypertension

  • No preview · Article · Jul 2013 · European Journal of Nuclear Medicine
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    Preview · Article · Feb 2013 · The Journal of Headache and Pain
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    Preview · Article · Feb 2013 · The Journal of Headache and Pain
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    Preview · Article · Feb 2013 · The Journal of Headache and Pain
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    ABSTRACT: To investigate whether a single optimal vaccination strategy exists across countries to deal with a future influenza pandemic by comparing the cost effectiveness of different strategies in various pandemic scenarios for three European countries. Economic and epidemic modelling study. General populations in Germany, the Netherlands, and the United Kingdom. Country specific patterns of social contact and demographic data. An age structured susceptible-exposed-infected-recovered transmission model that describes how an influenza A virus will spread in the populations of Germany, the Netherlands, and the United Kingdom. Comparison of four vaccination strategies: no vaccination, blanket vaccination, vaccination of elderly people (≥ 65 years), and vaccination of high transmitters (5-19 years). The four strategies were evaluated for scenarios in which a vaccine became available early or at the peak of the pandemic, and in which either everyone was initially susceptible or older age groups had pre-existing immunity. Cost per quality adjusted life years (QALYs) gained. All vaccination strategies were cost effective (incremental cost per QALY gained, comparing intervention with non-intervention). In scenarios where the vaccine became available at the peak of the pandemic and there was pre-existing immunity among elderly people the incremental cost effectiveness ratios for vaccinating high transmitters were €7325 (£5815; $10,470) per QALY gained for Germany, €10,216 per QALY gained for the Netherlands, and €7280 per QALY gained for the United Kingdom. The most cost effective strategy not only differed across the pandemic scenarios but also between countries. Specifically, when the vaccine was available early in the pandemic and there was no pre-existing immunity, in Germany it would be most cost effective to vaccinate elderly people ( €940 per QALY gained), whereas it would be most cost effective to vaccinate high transmitters in both the Netherlands (€525 per QALY gained) and the United Kingdom (€163 per QALY gained). This difference in optimal strategies was due to differences in the demographic characteristics of the countries: Germany has a significantly higher proportion of elderly people compared with the Netherlands and the United Kingdom. No single vaccination strategy was most cost effective across countries. With aging populations, pre-existing immunity in particular could be of crucial importance for the cost effectiveness of options to mitigate a future influenza pandemic.
    Full-text · Article · Jul 2012 · BMJ Clinical Research
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    ABSTRACT: To perform a cost-effectiveness analysis and to identify the cost-effectiveness affordability levels for a newborn universal vaccination program against hepatitis B virus (HBV) in Vietnam.Methods By using a Markov model, we simulated a Vietnamese birth cohort using 1,639,000 newborns in 2002 and estimated the incremental cost-effectiveness ratios for quality-adjusted life-year gained following universal newborn HBV vaccination. Two types of analyses were performed, including and excluding expenditures on the treatment of chronic hepatitis B and its complications. We used Monte Carlo simulations to examine cost-effectiveness acceptability and affordability from the payer's perspective and constructed a cost-effectiveness affordability curve to assess the costs and health effects of the program.ResultsIn the base-case analysis, newborn universal HBV vaccination reduced the carrier rate by 58% at a cost of US $42 per carrier averted. From the payer's perspective, incremental cost-effectiveness ratio per quality-adjusted life-year gained was US $3.77, much lower than the 2002 per-capita gross domestic product of US $440. Vaccination could potentially be affordable starting at a US $2.1 million budget. At the cost-effectiveness threshold of US $3.77 per quality-adjusted life-year and an annual budget of US $5.9 million, the probability that vaccination will be both cost-effective and affordable was 21%.Conclusions Universal newborn HBV vaccination is highly cost-effective in Vietnam. In low-income, high-endemic countries, where funds are limited and the economic results are uncertain, our findings on the cost-effectiveness affordability options may assist decision makers in proper health investments.
    No preview · Article · May 2012
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    M H Rozenbaum · R De Vries · H H LE · M J Postma
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    ABSTRACT: The aim of this study was to investigate the optimal pertussis booster vaccination strategy for The Netherlands. A realistic age-structured deterministic model was designed. Assuming a steady-state situation and correcting for underreporting, the model was calibrated using notification data from the period 1996-2000. Several sensitivity analyses were performed to explore the impact of different assumptions for parameters surrounded by uncertainty (e.g. duration of protection after natural infection, underreporting factors, and transmission probabilities). The optimal age of an additional booster dose is in the range of 10-15 years, and implementation of this booster dose will reduce both symptomatic and asymptomatic infections, although the incidence of symptomatic infections in older age groups will increase. The impact of the different assumptions used in the model was in general limited. We conclude that over a wide range of assumptions, an additional booster dose can reduce the incidence of pertussis in the population.
    Full-text · Article · Nov 2011 · Epidemiology and Infection
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    ABSTRACT: Phospholipid transfer protein (PLTP) is an emerging cardiometabolic risk marker that is important in high-density lipoprotein (HDL) and triglyceride metabolism. Plasma PLTP activity is elevated in type 2 diabetes mellitus, whereas glucose may regulate PLTP gene transcription in vitro. Of interest, common PLTP variations that predict cardiovascular disease have been identified recently. We investigated whether the diabetic state is able to amplify relationships between obesity and PLTP gene variations with circulating PLTP levels. Plasma PLTP activity (using a phospholipid vesicles-HDL system), PLTP gene score [number of PLTP activity-decreasing alleles based on two tagging polymorphisms (rs378114 and rs60- 65904)] and waist circumference were determined in two Dutch cohorts comprising 237 patients with type 2 diabetes and 78 control subjects. Patients with diabetes were more obese (P < 0.001 for prevalence of increased waist circumference) and had 13% higher plasma PLTP activity (P < 0.001). PLTP gene score was not different in diabetic and control subjects (P = 0.40). PLTP activity was highest in patients with diabetes with an enlarged waist and lowest in control subjects with a normal waist circumference (P < 0.001). Multiple linear regression analysis revealed a positive interaction between diabetes status and waist circumference on PLTP activity (β = 0.200, P = 0.005). Furthermore, diabetes status (β = -0.485, P = 0.046) or HbA1c (β = -0.240, P = 0.035) interacted with PLTP gene score to affect PLTP activity. Type 2 diabetes and enlarged waist circumference interact to impact on plasma PLTP activity. Diabetes may also amplify the association between plasma PLTP activity and common PLTP gene variations. Our findings support the hypothesis that diabetes-environment and diabetes-gene interactions govern plasma PLTP activity.
    No preview · Article · Oct 2011 · Journal of Internal Medicine
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    ABSTRACT: Objective. To investigate whether advanced glycation endproducts (AGEs) in the skin are increased in patients with systemic sclerosis (SSc) and are related to the presence of disease-related and traditional cardiovascular risk factors. Methods. Skin autofluorescence, as a measure for the accumulation of AGEs, was assessed by measuring UV-A light excitation-emission matrices (AF-EEMS) in 41 SSc patients and 41 age- and sex-matched controls. Traditional cardiovascular risk factors and disease-related risk factors were recorded. Results. Skin AF-EEMS did not differ between SSc patients and controls (1.68 ± 0.58 a.u. versus 1.63 ± 0.41 a.u., P = 0.684). Skin AF-EEMS in SSc patients was associated with levels of CRP (r = 0.44, P = 0.004), Medsger's severity scale (r = 0.45, P = 0.006), and use of agents intervening in the renin-angiotensin system (r = 0.33, P = 0.027). When analysing SSc patients and controls together, in multivariate analysis, only age and use of agents intervening in the renin-angiotensin system were independently associated with AF-EEMS. Conclusion. These data demonstrate that skin AGEs are not increased in SSc patients.
    Full-text · Article · Sep 2011 · International Journal of Rheumatology
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    ABSTRACT: There has been a large increase in the incidence of invasive fungal infections (IFIs) over the past decades, largely because of the increasing size of the population at risk. One of the major risk groups for IFIs are patients with haematological malignancies treated with cytotoxic chemotherapy or undergoing haematopoietic stem cell transplantation. These IFIs are associated with high morbidity and mortality rates. Consequently, as the diagnosis of IFIs is difficult, antifungal prophylaxis is desirable in high-risk patients. Furthermore, as the economic impact of IFIs is also significant, it is important to assess the cost benefit and cost effectiveness of each prophylactic agent in order to aid decisions concerning which prophylactic agent provides the best value for limited healthcare resources. This article systematically reviews the available pharmacoeconomic evidence regarding antifungal prophylaxis in immunocompromised patients treated for haematological malignancies. Furthermore, specific points of interest concerning economic analyses of antifungal prophylaxis are briefly discussed. Considering the available evidence, antifungal prophylaxis in immunocompromised patients treated for haematological malignancies seems to be an intervention with favourable cost-benefit, cost-effectiveness and cost-saving potential. Furthermore, recently introduced antifungal agents seem to be attractive alternatives to fluconazole from a pharmacoeconomic point of view. However, due to wide heterogeneity in patient characteristics, underlying diseases, hospital settings and study methods in the included economic studies, as well as the lack of 'head-to-head' trials, it is difficult to find clear evidence of the economic advantages of a single prophylactic agent. Furthermore, we show that the results of cost-effectiveness analyses are highly dependent on several crucial factors that influence the baseline IFI incidence rates and, therefore, differ per patient population or region.
    No preview · Article · Jun 2011 · PharmacoEconomics

  • No preview · Article · Jun 2011 · Atherosclerosis Supplements
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    HAT Tu · M van Hurst · HJ Woerdenbag · R de Vries · MJ Postma

    Preview · Article · Nov 2010 · Value in Health
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    P Pechlivanoglou · HH Le · R De Vries · MJ Postma

    Full-text · Article · Nov 2010 · Value in Health
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    HAT Tu · R de Vries · HJ Woerdenbag · M van Hulst · MJ Postma
    [Show abstract] [Hide abstract]
    ABSTRACT: Objectives To perform a cost-effectiveness analysis and to identify the cost-effectiveness affordability levels for a newborn universal vaccination program against hepatitis B virus (HBV) in Vietnam.Methods By using a Markov model, we simulated a Vietnamese birth cohort using 1,639,000 newborns in 2002 and estimated the incremental cost-effectiveness ratios for quality-adjusted life-year gained following universal newborn HBV vaccination. Two types of analyses were performed, including and excluding expenditures on the treatment of chronic hepatitis B and its complications. We used Monte Carlo simulations to examine cost-effectiveness acceptability and affordability from the payer's perspective and constructed a cost-effectiveness affordability curve to assess the costs and health effects of the program.ResultsIn the base-case analysis, newborn universal HBV vaccination reduced the carrier rate by 58% at a cost of US $42 per carrier averted. From the payer's perspective, incremental cost-effectiveness ratio per quality-adjusted life-year gained was US $3.77, much lower than the 2002 per-capita gross domestic product of US $440. Vaccination could potentially be affordable starting at a US $2.1 million budget. At the cost-effectiveness threshold of US $3.77 per quality-adjusted life-year and an annual budget of US $5.9 million, the probability that vaccination will be both cost-effective and affordable was 21%.Conclusions Universal newborn HBV vaccination is highly cost-effective in Vietnam. In low-income, high-endemic countries, where funds are limited and the economic results are uncertain, our findings on the cost-effectiveness affordability options may assist decision makers in proper health investments.
    Full-text · Article · Nov 2010 · Value in Health
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    Dataset: Appendix S1
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    ABSTRACT: (0.15 MB DOC)
    Preview · Dataset · Oct 2010
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    ABSTRACT: Despite widespread immunization programs, a clear increase in pertussis incidence is apparent in many developed countries during the last decades. Consequently, additional immunization strategies are considered to reduce the burden of disease. The aim of this study is to design an individual-based stochastic dynamic framework to model pertussis transmission in the population in order to predict the epidemiologic and economic consequences of the implementation of universal booster vaccination programs. Using this framework, we estimate the cost-effectiveness of universal adolescent pertussis booster vaccination at the age of 12 years in the Netherlands.
    Full-text · Article · Oct 2010 · PLoS ONE
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    ABSTRACT: The sensory neuropeptide calcitonin gene-related peptide (CGRP) plays a role in primary headaches, and CGRP receptor antagonists are effective in migraine treatment. CGRP is a potent vasodilator, raising the possibility that antagonism of its receptor could have cardiovascular effects. We therefore investigated the effects of the antimigraine CGRP receptor antagonist telcagepant (MK-0974) [N-[(3R,6S)-6-(2,3-difluorophenyl)-2-oxo-1-(2,2,2-trifluoroethyl)azepan-3-yl]-4-(2-oxo-2,3-dihydro-1H-imidazo[4,5-b]pyridine-1-yl)piperidine-1-carboxamide] on human isolated coronary arteries. Arteries with different internal diameters were studied to assess the potential for differential effects across the coronary vascular bed. The concentration-dependent relaxation responses to human alphaCGRP were greater in distal coronary arteries (i.d. 600-1000 microm; E(max) = 83 +/- 7%) than proximal coronary arteries (i.d. 2-3 mm; E(max) = 23 +/- 9%), coronary arteries from explanted hearts (i.d. 3-5 mm; E(max) = 11 +/- 3%), and coronary arterioles (i.d. 200-300 microm; E(max) = 15 +/- 7%). Telcagepant alone did not induce contraction or relaxation of these coronary blood vessels. Pretreatment with telcagepant (10 nM to 1 microM) antagonized alphaCGRP-induced relaxation competitively in distal coronary arteries (pA(2) = 8.43 +/- 0.24) and proximal coronary arteries and coronary arterioles (1 microM telcagepant, giving pK(B) = 7.89 +/- 0.13 and 7.78 +/- 0.16, respectively). alphaCGRP significantly increased cAMP levels in distal, but not proximal, coronary arteries, and this was abolished by pretreatment with telcagepant. Immunohistochemistry revealed the expression and colocalization of the CGRP receptor elements calcitonin-like receptor and receptor activity-modifying protein 1 in the smooth muscle cells in the media layer of human coronary arteries. These findings in vitro support the cardiovascular safety of CGRP receptor antagonists and suggest that telcagepant is unlikely to induce coronary side effects under normal cardiovascular conditions.
    Full-text · Article · Sep 2010 · Journal of Pharmacology and Experimental Therapeutics
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    ABSTRACT: Pertussis is a highly contagious respiratory disease. Despite a high rate of vaccine coverage through the Dutch national immunization program, the incidence of pertussis remains high in the Netherlands and the risk of infection continues. Because pertussis is most severe in unimmunized infants and infants who have only received some of the recommended doses, new pertussis immunization strategies should be considered to protect this vulnerable population. This study was designed to estimate the cost-effectiveness of 3 new immunization strategies for possible addition to the current Dutch national immunization program: immunization of the infant at birth, immunization of the parents immediately after birth of the child (cocooning), and maternal immunization during the third trimester of pregnancy. A literature search was performed in the PubMed database for articles published in English, German, and Dutch using the following terms: pertussis, whooping cough, vaccination strategies, maternal immunization, cocooning, at birth, vaccine efficacy, mortality, underreporting, prevalence, incidence, and cost-effectiveness. A decision-tree model was developed for this analysis, and data on pertussis morbidity and costs were collected consistently for different age groups (infants <1 year of age and adults 25 to 34 years of age). The size of the infant cohort was set at 200,000 to approximate previous Dutch birth cohorts. The size of the adult cohort was set at 401,380 parents for the cocooning strategy and 201,380 mothers for the maternal immunization strategy. Health benefits (quality-adjusted life-years [QALYs]) and costs were estimated in both cohorts for each of the 3 immunization strate- gies. Incremental cost-effectiveness ratios were calculated from both a payer's and a societal perspective. The robustness of the results was determined through sensitivity analysis. In the base-case analysis, cocooning and maternal immunization were found to be effective in reducing the incidence of pertussis among infants (123 and 174 infant cases were expected to be prevented, respectively). Furthermore, cocooning and maternal immunization were estimated to be cost-effective from a payer's perspective (euro4600 [US $6400]/QALY and euro3500 [$4900]/QALY, respectively) and even cost-saving from a societal perspective (savings of up to euro7200 [$10,100] and euro5000 [$7000], respectively). Sensitivity analyses revealed that favorable cost-effectiveness was generally robust. In the sensitivity analysis, the cost-effectiveness of cocooning and maternal immunization was mostly sensitive for changes in assumptions on underreporting (200-fold increase in reported number of symptomatic cases) of pertussis disease and infection. With no underreporting, the ICER was estimated at euro211,900 ($296,700)/QALY for cocooning and euro81,600 ($114,200)/QALY for maternal immunization from a payer's perspective. However, even at much lower levels of underreporting (20- to 30-fold increase in incidence), cost-effectiveness remained favorable. The cost-effectiveness of the third strategy, at-birth immunization, was highly unfavorable (euro329,900 [$461,900]/QALY from a payer's perspective and euro330,100 [$462,100]/ QALY from a societal perspective). This study estimated that the addition of cocooning or maternal immunization to the current Dutch national immunization program likely would be cost-effective or even cost-saving. These estimates were mainly due to reduction in the number of cases among parents, which are likely to be mild and therefore would largely remain unreported. Immunization at birth was not a cost-effective strategy. Cocooning was the most expensive intervention to implement; however, it resulted in the highest number of QALYs gained (mainly in adults). Maternal immunization would offer better protection of infants, due to maternally acquired antibodies.
    No preview · Article · Aug 2010 · Clinical Therapeutics

Publication Stats

1k Citations
276.54 Total Impact Points

Institutions

  • 2013
    • Ziekenhuis Tjongerschans
      Heerenveen, Friesland, Netherlands
  • 2010-2013
    • Erasmus MC
      Rotterdam, South Holland, Netherlands
  • 2004-2012
    • University of Groningen
      • • Department of Pharmacy
      • • Department of Pharmacoepidemiology and Pharmacoeconomics
      • • Department of Endocrinology
      • • PharmacoEpidemiology and PharmacoEconomics (PE²) Unit
      Groningen, Groningen, Netherlands
  • 1993-2010
    • Erasmus Universiteit Rotterdam
      • • Department of Internal Medicine
      • • Department of Biochemistry
      • • Department of Pharmacology
      Rotterdam, South Holland, Netherlands
  • 2004-2007
    • Universitair Medisch Centrum Groningen
      • Department of Internal Medicine
      Groningen, Groningen, Netherlands
  • 2005
    • Martini Ziekenhuis
      Groningen, Groningen, Netherlands
  • 2003-2005
    • Leiden University Medical Centre
      • Department of Immunhematology and Blood Transfusion
      Leyden, South Holland, Netherlands
  • 1997
    • University of Belgrade
      Beograd, Central Serbia, Serbia