• Low Free Testosterone and Prostate Cancer Risk: A Collaborative Analysis of 20 Prospective Studies.

      Watts, Eleanor L; Appleby, Paul N; Perez-Cornago, Aurora; Bueno-de-Mesquita, H Bas; Chan, June M; Chen, Chu; Cohn, Barbara A; Cook, Michael B; Flicker, Leon; Freedman, Neal D; et al. (2018-08-01)
      Experimental and clinical evidence implicates testosterone in the aetiology of prostate cancer. Variation across the normal range of circulating free testosterone concentrations may not lead to changes in prostate biology, unless circulating concentrations are low. This may also apply to prostate cancer risk, but this has not been investigated in an epidemiological setting.
    • Low gonorrhoea antimicrobial resistance and culture positivity rates in general practice: a pilot study.

      Visser, Maartje; van Westreenen, Mireille; van Bergen, Jan; van Benthem, Birgit H B (2019-04-30)
    • Low probability of a dilution effect for Lyme borreliosis in Belgian forests.

      Ruyts, Sanne C; Landuyt, Dries; Ampoorter, Evy; Heylen, Dieter; Ehrmann, Steffen; Coipan, Elena C; Matthysen, Erik; Sprong, Hein; Verheyen, Kris (2018-04-22)
      An increasing number of studies have investigated the consequences of biodiversity loss for the occurrence of vector-borne diseases such as Lyme borreliosis, the most common tick-borne disease in the northern hemisphere. As host species differ in their ability to transmit the Lyme borreliosis bacteria Borrelia burgdorferi s.l. to ticks, increased host diversity can decrease disease prevalence by increasing the proportion of dilution hosts, host species that transmit pathogens less efficiently. Previous research shows that Lyme borreliosis risk differs between forest types and suggests that a higher diversity of host species might dilute the contribution of small rodents to infect ticks with B. afzelii, a common Borrelia genospecies. However, empirical evidence for a dilution effect in Europe is largely lacking. We tested the dilution effect hypothesis in 19 Belgian forest stands of different forest types along a diversity gradient. We used empirical data and a Bayesian belief network to investigate the impact of the proportion of dilution hosts on the density of ticks infected with B. afzelii, and identified the key drivers determining the density of infected ticks, which is a measure of human infection risk. Densities of ticks and B. afzelii infection prevalence differed between forest types, but the model indicated that the density of infected ticks is hardly affected by dilution. The most important variables explaining variability in disease risk were related to the density of ticks. Combining empirical data with a model-based approach supported decision making to reduce tick-borne disease risk. We found a low probability of a dilution effect for Lyme borreliosis in a north-western European context. We emphasize that under these circumstances, Lyme borreliosis prevention should rather aim at reducing tick-human contact rate instead of attempting to increase the proportion of dilution hosts.
    • Lower antibody functionality in middle-aged adults compared to adolescents after primary meningococcal vaccination: Role of IgM.

      van der Heiden, Marieke; van Ravenhorst, Mariette B; Bogaard, Marjan; Boots, Annemieke M H; Berbers, Guy A M; Buisman, Anne-Marie (2017-12-26)
      Successful vaccination of elderly persons is often hampered by immunological ageing, leaving part of the elderly population vulnerable for infectious diseases. As an alternative, timely vaccinations might be administered at middle-age, before reaching old age. Studies evaluating the immunological fitness of middle-aged adults are warranted. In this study we compared the immunogenicity of a primary meningococcal vaccination in Dutch middle-aged adults with that in adolescents, in order to gain knowledge on the early signs of immune ageing.
    • The Maastricht FFQ: Development and validation of a comprehensive food frequency questionnaire for the Maastricht study.

      van Dongen, Martien Cjm; Wijckmans-Duysens, Nicole E G; den Biggelaar, Louise Jcj; Ocké, Marga C; Meijboom, Saskia; Brants, Henny Am; de Vries, Jeanne Hm; Feskens, Edith Jm; Bueno-de-Mesquita, H Bas; Geelen, Anouk; et al. (2018-10-26)
      The aim of this study was to develop and validate a comprehensive food frequency questionnaire (FFQ) for The Maastricht Study, a population-based prospective cohort study in Maastricht, The Netherlands. Item selection for the FFQ was based on explained variation and contribution to intake of energy and 24 nutrients. For validation, the FFQ was completed by 135 participants (25-70 y of age) of the Nutrition Questionnaires plus study. Per person, on average 2.8 (range 1-5) telephone-based 24-h dietary recalls (24HRs), two 24-h urinary samples, and one blood sample were available. Validity of 54 nutrients and 22 food groups was assessed by ranking agreement, correlation coefficients, attenuation factors, and ultimately deattenuated correlation coefficients (validity coefficients). Median correlation coefficients for energy and macronutrients, micronutrients, and food groups were 0.45, 0.36, and 0.38, respectively. Median deattenuated correlation coefficients were 0.53 for energy and macronutrients, 0.45 for micronutrients, and 0.64 for food groups, being >0.50 for 18 of 22 macronutrients, 16 of 30 micronutrients and >0.50 for 17 of 22 food groups. The FFQ underestimated protein and potassium intake compared with 24-h urinary nitrogen and potassium excretion by -18% and -2%, respectively. Correlation coefficients ranged from 0.50 and 0.55 for (fatty) fish intake and plasma eicosapentaenoic acid and docosahexaenoic acid, and from 0.26 to 0.42 between fruit and vegetable intake and plasma carotenoids. Overall, the validity of the 253-item Maastricht FFQ was satisfactory. The comprehensiveness of this FFQ make it well suited for use in The Maastricht Study and similar populations.
    • De macht en onmacht van richtlijnen

      Verheij TJM; Velden AW van der; Lubben M van der (2018-05-28)
    • Making Vector-Borne Disease Surveillance Work: New Opportunities From the SDG Perspectives.

      Braks, Marieta; Giglio, Giorgia; Tomassone, Laura; Sprong, Hein; Leslie, Teresa (2019-01-01)
    • Malaria in Eritrean migrants newly arrived in seven European countries, 2011 to 2016.

      Sondén, Klara; Rolling, Thierry; Wångdahl, Andreas; Ydring, Elsie; Vygen-Bonnet, Sabine; Kobbe, Robert; Douhan, Johan; Hammar, Ulf; Duijster, Janneke; de Gier, Brechje; et al. (2019-01-01)
      Global migration has resulted in a large number of asylum applications in Europe. In 2014, clusters of
    • Malariameldingen in 2005: Evaluatie van de richtlijnen van het Landelijk Coördinatiecentrum Reizigersadvisering (LCR) voor malariaprofylaxe

      Sondera, G J B; Plas, Simone M van der (RIVM, 2006-08-01)
      In The Netherlands, malaria is a notifiable disease in group C since 1999: the laboratory where the patient tested positive has to report the test results, together with a few demographic data, to the National Center for Disease Control (CIb). Since January 2005, the National Coordination Center for Travelers Health Advice (LCR) added some questions to the voluntary part of these reports in order to obtain more insight in the prevalence of malaria in people who used prophylaxis according to the LCR guidelines, and to evaluate these guidelines. The goal of the LCR guidelines is to prevent malaria caused by P. falciparum. All reported cases with a disease onset date in 2005 were evaluated. In 2005, 288 cases of malaria were reported. Seventy-five (26%) malaria patients used chemoprophylaxis. In total, 32 (11%) contracted malaria despite the use of chemoprophylaxis according to the LCR guidelines. Eight of these cases concerned malaria caused by P. falciparum. Four of these had used second choice chemoprophylaxis, to which parasitic resistance is common. In the blood sample of one patient no mefloquine was detected. Of the other three, the thick smear or EDTA blood was not available for resistance tests. Most likely, all other cases had a delayed onset malaria, which cannot be prevented by the currently available chemoprophylaxis. Based on these data, we conclude that the LCR guidelines are still valid. It is advised that in cases of breakthrough malaria caused by P. falciparum blood samples are taken to determine chloroquine or mefloquine levels where applicable, and to save EDTA blood for molecular confirmation of the species and determination of resistant parasites.
    • Managing Innovations: A Study of the Implementation of Electronic Medical Records in Dutch Hospitals

      Koster, Ferry; Lambooij, Mattijs; Department of Sociology, Erasmus University Rotterdam, Burgemeester Oudlaan 50, 3000 DR Rotterdam, The Netherlands; Department of Quality in Health Care and Health Economics, National Institute of Public Health and the Environment, A. Van Leeuwenhoeklaan 9, 3720 BA, Bilthoven, The Netherlands (2018-01-10)
    • Mandated lowering of toxicants in cigarette smoke: a description of the World Health Organization TobReg proposal.

      Burns, D M; Dybing, E; Gray, N; Hecht, S; Anderson, C; Sanner, T; O'Connor, R; Djordjevic, M; Dresler, C; Hainaut, P; et al. (2008-04)
    • Mapping soil biodiversity in Europe and the Netherlands.

      Rutgers, M; van Leeuwen, JP; Vrebos, D; van Wijnen, HJ; Schouten, T; de Goede, RGM (2019-10-14)
    • Mapping the Dutch SNOMED CT subset to Omaha System, NANDA International and International Classification of Functioning, Disability and Health.

      Kieft, R A M M; Vreeke, E M; de Groot, E M; de Graaf-Waar, H I; van Gool, C H; Koster, N; Ten Napel, H; Francke, A L; Delnoij, D M J (2018-03)
      Nurses register data in electronic health records, which can use various terminology and coding systems. The net result is that information cannot be exchanged and reused properly, for example when a patient is transferred from one care setting to another. A nursing subset of patient problems was therefore developed in the Netherlands, based on comparable and exchangeable terms that are used throughout the healthcare sector and elsewhere (semantic interoperability). The purpose of the current research is to develop a mapping between the subset of patient problems and three classifications in order to improve the exchangeability of data. Those classifications are the Omaha System, NANDA International, and ICF (the International Classification of Functioning, Disability and Health).
    • Maternal body mass index, gestational weight gain, and the risk of overweight and obesity across childhood: An individual participant data meta-analysis.

      Voerman, Ellis; Santos, Susana; Patro Golab, Bernadeta; Amiano, Pilar; Ballester, Ferran; Barros, Henrique; Bergström, Anna; Charles, Marie-Aline; Chatzi, Leda; Chevrier, Cécile; et al. (2019-02-01)
      Maternal obesity and excessive gestational weight gain may have persistent effects on offspring fat development. However, it remains unclear whether these effects differ by severity of obesity, and whether these effects are restricted to the extremes of maternal body mass index (BMI) and gestational weight gain. We aimed to assess the separate and combined associations of maternal BMI and gestational weight gain with the risk of overweight/obesity throughout childhood, and their population impact. We conducted an individual participant data meta-analysis of data from 162,129 mothers and their children from 37 pregnancy and birth cohort studies from Europe, North America, and Australia. We assessed the individual and combined associations of maternal pre-pregnancy BMI and gestational weight gain, both in clinical categories and across their full ranges, with the risks of overweight/obesity in early (2.0-5.0 years), mid (5.0-10.0 years) and late childhood (10.0-18.0 years), using multilevel binary logistic regression models with a random intercept at cohort level adjusted for maternal sociodemographic and lifestyle-related characteristics. We observed that higher maternal pre-pregnancy BMI and gestational weight gain both in clinical categories and across their full ranges were associated with higher risks of childhood overweight/obesity, with the strongest effects in late childhood (odds ratios [ORs] for overweight/obesity in early, mid, and late childhood, respectively: OR 1.66 [95% CI: 1.56, 1.78], OR 1.91 [95% CI: 1.85, 1.98], and OR 2.28 [95% CI: 2.08, 2.50] for maternal overweight; OR 2.43 [95% CI: 2.24, 2.64], OR 3.12 [95% CI: 2.98, 3.27], and OR 4.47 [95% CI: 3.99, 5.23] for maternal obesity; and OR 1.39 [95% CI: 1.30, 1.49], OR 1.55 [95% CI: 1.49, 1.60], and OR 1.72 [95% CI: 1.56, 1.91] for excessive gestational weight gain). The proportions of childhood overweight/obesity prevalence attributable to maternal overweight, maternal obesity, and excessive gestational weight gain ranged from 10.2% to 21.6%. Relative to the effect of maternal BMI, excessive gestational weight gain only slightly increased the risk of childhood overweight/obesity within each clinical BMI category (p-values for interactions of maternal BMI with gestational weight gain: p = 0.038, p < 0.001, and p = 0.637 in early, mid, and late childhood, respectively). Limitations of this study include the self-report of maternal BMI and gestational weight gain for some of the cohorts, and the potential of residual confounding. Also, as this study only included participants from Europe, North America, and Australia, results need to be interpreted with caution with respect to other populations. In this study, higher maternal pre-pregnancy BMI and gestational weight gain were associated with an increased risk of childhood overweight/obesity, with the strongest effects at later ages. The additional effect of gestational weight gain in women who are overweight or obese before pregnancy is small. Given the large population impact, future intervention trials aiming to reduce the prevalence of childhood overweight and obesity should focus on maternal weight status before pregnancy, in addition to weight gain during pregnancy.
    • Maternal measles antibodies and their influence on all-cause mortality following measles vaccination: an alternative to measure very low maternal antibody levels.

      Smits, Gaby; Stabell Benn, Christine; Whittle, Hilton; van Binnendijk, Rob; Aaby, Peter; van der Klis, Fiona (2018-10-16)
      It was previously shown by hemagglutination inhibition that measles-vaccination in the presence of maternal measles antibodies was associated with reduced all-cause mortality. We confirmed this serological association using a multiplexed immunoassay as a sensitive alternative and estimated a threshold concentration (28.7 mIU/ml), that correlates with lower all-cause mortality (p=0.02).
    • Maternal pertussis vaccination and its effects on the immune response of infants aged up to 12 months in the Netherlands: an open-label, parallel, randomised controlled trial.

      Barug, Daan; Pronk, Inge; van Houten, Marlies A; Versteegh, Florens G A; Knol, Mirjam J; van de Kassteele, Jan; Berbers, Guy A M; Sanders, Elisabeth A M; Rots, Nynke Y (2019-04-01)
      Maternal tetanus, diphtheria, and acellular pertussis (Tdap) vaccination offers protection for neonates against clinical pertussis until primary vaccinations, but maternal antibodies also interfere with infants' immune responses to primary vaccinations. We investigated the effect of maternal Tdap vaccination on the pertussis antibody responses of infants starting primary vaccinations at age 3 months. In an open-label, parallel, randomised, controlled trial, pregnant women aged 18-40 years with a low risk of pregnancy complications were recruited through independent midwives at 36 midwife clinics in the Netherlands and received Tdap vaccination either at 30-32 weeks of pregnancy (maternal Tdap group) or within 48 h after delivery (control group). All term-born infants were vaccinated with the diphtheria, tetanus, and pertussis-inactivated poliomyelitis-Haemophilus influenzae type B-hepatitis B six-in-one vaccine and a ten-valent pneumococcal vaccine at 3 months, 5 months, and 11 months. Randomisation was done using a number generator in a 1:1 ratio and with sealed envelopes. Participants and clinical trial staff were not masked, but laboratory technicians were unaware of study group assignments. The primary endpoint was serum IgG pertussis toxin antibody concentrations at age 3 months. Cord blood and infant blood samples were collected at age 2 months, 3 months, 6 months, 11 months, and 12 months. Analysis was done by modified intention to treat with all randomly assigned participants in case a laboratory result was available. This trial is registered with ClinicaltTrialsRegister.eu (EudraCT 2012-004006-9) and trialregister.nl (NTR number NTR4314). The trial is now closed to new participants. Between Jan 16, 2014, and March 4, 2016, 118 pregnant women were enrolled into our study, with 58 in the maternal Tdap group and 60 in the control group. The geometric mean concentration (GMC) of pertussis toxin antibodies were higher in infants in the maternal Tdap group than in the control group infants at age 3 months (GMC ratio 16·6, 95% CI 10·9-25·2) and also significantly higher compared with control infants at age 2 months. After primary vaccinations, antibody concentrations for pertussis toxin, filamentous haemagglutinin, and pertactin were significantly lower at all timepoints in infants of the maternal Tdap group than in infants in the control group. No safety issues after maternal Tdap vaccination were encountered. In view of the high pertussis toxin antibody concentrations at age 3 months, maternal vaccination supports a delay of the first pertussis vaccination in infants until at least age 3 months. Maternal antibody interference affects antibody concentrations after primary and booster vaccinations. The clinical consequences of this interference remain to be established.
    • Maternal Smoking during Pregnancy and Early Childhood and Development of Asthma and Rhinoconjunctivitis - a MeDALL Project.

      Thacher, Jesse D; Gehring, Ulrike; Gruzieva, Olena; Standl, Marie; Pershagen, Göran; Bauer, Carl-Peter; Berdel, Dietrich; Keller, Theresa; Koletzko, Sibylle; Koppelman, Gerard H; et al. (2018)
      The role of tobacco smoke exposure in the development and persistence of asthma and rhinoconjunctivitis through childhood into adolescence is unclear.