Scientific research Nijmegen Biomedical Study

About NBS

The NBS was initiated by the Department for Health Evidence, the Department of Laboratory Medicine and the Department of Internal Medicine of the Radboud university medical center (RUMC). The Department of Human Genetics of the RUMC has joined the NBS project team in a later stage. Also, the municipality Nijmegen and the community health service Nijmegen were involved as collaborators in NBS1. The NBS is financed by the departments and agencies mentioned above and a grant from the so called ‘Vrije Beleidsruimte’ of the RUMC.

The NBS consists of a number of phases. Because too extensive measurements have a negative impact on participant response, we chose a phased model in which people in first instance only received a limited questionnaire and an invitation to donate a blood sample (NBS1). In following phases, they received an invitation for an extensive examination and additional questionnaires (NBS2-5). In phase 2-5 we joined forces with other departments within RUMC and the department of Human Nutrition of Wageningen University and Research Centre that were interested in specific data.

More information? Read the detailed description of the NBS in the cohort profile.

• NBS1

  In collaboration with the municipality of Nijmegen and the community health service Nijmegen the first phase of the NBS was conducted between 2001 and 2003. First, the logistic set-up of the NBS1 was tested in a pilot study that was performed between November 2001 and February 2002. A random sample of names and addresses of 650 males and females of 18 years and older was obtained via the registers of the municipality Nijmegen. All have received a questionnaire (QN) with questions related to lifestyle, health, disease, and medication use; 342 QNS were filled out (response 53%). Of those people that have returned a completed questionnaire, 262 (77%) have also donated a sample of blood. The procedure of blood sampling was slightly altered after the pilot study; the number of options with regard to time of donation were increased and the number of places for blood donation were decreased.
  
  Then, a random sample from the register of the population of Nijmegen, stratified on sex and 5-year age groups, was taken on July 1 2002. All men and women over 18 years, not living in institutions and rest homes, and able to fill out a Dutch questionnaire, were eligible. In total 22,451 inhabitants of  the municipality of Nijmegen received an invitation to fill out a postal questionnaire on, e.g., lifestyle and medical history, and to donate an 8.5 ml blood sample in a serum separator tube and a 10 ml EDTA blood sample. 96% was of Dutch nationality and 79% was born in the Netherlands.

  The age distribution is depicted in Table 1.

  Age group	Number (%)
  18 – 29 years	3370 (15.0%)
  30 – 39 years	3438 (15.3%)
  40 – 49 years	3242 (14.4%)
  50 – 59 years	3196 (14.2%)
  60 – 69 years	3203 (14.3%)
  70 – 79 years	3072 (13.7%)
  ≥ 80 years	2930 (13.1%)
  Total	22451

  Table 1: Age distribution age and sex stratified sample, July 1 2002

  
  The response to the questionnaire was 42% (N=9350). 69% (N=6468) of the responders donated blood samples (see Figure 1). For detailed information on the questions included in the NBS1 questionnaire see section ‘Researcher data'. The serum and plasma samples have been stored in the Radboud Biobank. A number of measurements have been performed in these samples and DNA has been isolated.
  
  
  Figure 1: Response to questionnaire (QN) and blood donation.

• NBS2

  Not all important health related questions could be answered using the data collected in NBS1. Therefore, in October/November 2005 we have approached all the NBS1 participants who had given permission for further research and asked them to fill out an additional questionnaire (NBS2 QN). This QN contained questions about a number of topics, including health and disease, pregnancy, mood and behaviour, daily activities, and memory. In addition, a part of these participants was asked to undergo supplementary examinations in the RUNMC, dependent on age, sex and questionnaire information. This supplementary examination consisted of, a.o., a food frequency questionnaire (FFQ), blood pressure measurements, measurement of length and weight, donation of a number of (fasting) blood samples and a urine sample, non-invasive measurements of atherosclerosis, cognitive tests, and a gait analysis.
  
  Several departments of the RUNMC were involved in the second phase of the NBS: General Internal Medicine, Endocrinology, Geriatrics, Neurology, Nephrology, Psychiatry, Rheumatology and Vascular Surgery. In addition, collaboration with the department of Human Nutrition of Wageningen University and Research Centre took place. All these departments have financially invested in NBS2.
  
  Below you can find an overview of the NBS2 per age category (based on age at November 1 2005) and the number of participants. The questionnaire for people below 70 years old, can be found here. The questionnaire for people above 70 years old, can be found here.

  Age below 50

  2926 NBS2 QNS were sent out, of which 1884 (64%) were completed. Between the years 2008 and 2010 people below the age of 50 were invited to fill out a food frequency questionnaire and to donate a blood and urine sample. This part of the study has been named NBS3.

  Age 50 to 70

  In this age group 2807 QNS were sent out; the response was 75% (2114 QNS). In addition, 1491 people participated in an extensive study from the department of Internal Medicine of the RUNMC: the NIMA study. For this study, participants visited the RUNMC once for donation of a blood sample, measurement of length, weight, blood pressure, and waist and hip circumference. During this same visit four different non-invasive measurements of atherosclerosis were performed, i.e. intima media thickness (IMT), endothelium function using flow-mediated dilatation (FMD), ankle-brachial index (ABI) and pulse-wave velocity (PWV). A large part of these participants has also filled out a FFQ (1168).
  
  In the meantime, a pilot for a follow-up study in this population has been performed: NBS-NIMA2. The pilot study, executed in 2011, included repeated measurements of NIMA (including FMD, IMT, the presence and thickness of plaques in the carotid arteries, ABI at rest and after exercise, PWV, and PWA), measurements of traditional and new clinical and biochemical measurements, including a questionnaire on life style habits and medical history, and evaluation of clinical endpoints. Venous blood was drawn and a urine sample was collected. The measurement protocol was exactly the same as in the NBS-NIMA 1 study. Hundred NBS2-NIMA1 participants were invited for the pilot; 95 individuals participated.

  Age over 70

  Of the 2253 NBS2 QNS that were sent out in this age category, 1596 have been filled in: a response of 71%. Also, 150 FFQs were sent out, of which 77 were filled in (response 51%). A selection of 300 people was approached for additional examinations by the department of Geriatrics, including cognitive tests, quantitative gait analysis, functional mobility tests and measurement of hand grip strength; one hundred people (33%) have participated.

• NBS3 and NBS4

  NBS3

  The collection of additional data in people below the age of 50 has been carried out as NBS3 between 2008 and 2010. NBS3 participants filled out a food frequency questionnaire. Fasting blood samples were obtained for determination of thyroid function, kidney function and CRP. Also urine was collected. In total, 2011 people were invited; 1053 sent in a food frequency questionnaire and 474 participants donated blood and urine.

  NBS4

  The questionnaire data of NBS1 and NBS2 have been used to answer a variety of research questions. To increase the compatibility and similarity in available data between the NBS and patient groups (cancer cases) that were frequently used for our research purposes, the NBS participants who had given consent for further research and were still alive were again contacted in 2008 and invited to fill out an additional questionnaire (NBS4). In total, 8109 people were approached and 5613 (69%) completed the questionnaire (see section ‘Researcher data’ for detailed information on included questions).

• NBS5

  NBS5 was executed in 2012. In total, 7,567 persons were invited, 3,833 questionnaires were filled out and returned (51%).

Organization

Project management

Coordinators

Others involved