Study on the prevalence and determinants of glucose intolerance in a Dutch caucasian population: the Hoorn Study

ISRCTN	ISRCTN33032170
DOI	https://doi.org/10.1186/ISRCTN33032170
ClinicalTrials.gov (NCT)	Nil known
Clinical Trials Information System (CTIS)	Nil known
Protocol serial number	Nil known
Sponsor	VU University Medical Center of Amsterdam
Funders	Amsterdam University Medical Centers, Nederlandse Organisatie voor Wetenschappelijk Onderzoek, ZonMw, European Union, Novartis Pharma, Diabetes Fonds, Netherlands Heart Foundation

Submission date: 16/12/2016
Registration date: 03/04/2017
Last edited: 20/06/2025

Recruitment status: No longer recruiting
Overall study status: Ongoing
Condition category: Nutritional, Metabolic, Endocrine

Prospectively registered

Protocol

Statistical analysis plan

Results

Individual participant data

Record updated in last year

Plain English summary of protocol

Background and study aims
Type 2 diabetes is a chronic (long-term) disorder where blood glucose (sugar) levels are too high. The prevalence of type 2 diabetes is increasing worldwide, bringing a high risk of complications of the eyes, kidneys and foot, and cardiovascular (heart) diseases. Many risk factors for diabetes have been identified. However, many factors are involved in type 2 diabetes and questions remain on interactions between risk factors. The aim of this study is to assess the prevalence and risk factors of impaired glucose metabolism (a pre-diabetic state) and diabetes in the general population.

Who can participate?
Men and women aged 50–75 randomly selected from the municipal registry in the year 1989

What does the study involve?
The participants visit the centre six times over 25 years to provide blood and urine samples, to be tested for diabetes, to be measured, and to complete questionnaires. Participants are followed up using the municipality register to check for the occurrence of chronic diseases.

What are the possible benefits and risks of participating?
There is minimal risk of participating, except for some bruising from blood drawn.

Where is the study run from?
Diabetes Zorgsysteem locatie Hoorn (Netherlands)

When is the study starting and how long is it expected to run for?
January 1989 to January 2080

Who is funding the study?
1. VU University Medical Center of Amsterdam
2. Nederlandse Organisatie voor Wetenschappelijk Onderzoek
3. ZonMw
4. European Union
5. Novartis Pharma
6. Diabetes Fonds
7. Netherlands Heart Foundation

Who is the main contact?
1. Prof Dr Joline Beulens
J.beulens@amsterdamumc.nl
2. Dr Femke Rutters
f.rutters@amsterdamumc.nl

Contact information

Prof Joline Beulens
Scientific

De Boelelaan 1089a
Amsterdam
1081 HV
Netherlands

Phone	+31 (0)20 4440367
Email	J.beulens@amsterdamumc.nl

Dr Femke Rutters
Scientific

De Boelelaan 1089a
Amsterdam
1081 HV
Netherlands

Phone	+31 (0)20 444 5860
Email	f.rutters@amsterdamumc.nl

Study information

Primary study design	Observational
Study design	Prospective observational study with five follow-up visits during a 25-year period, and ongoing registry of morbidity and mortality
Secondary study design	Longitudinal study
Study type	Participant information sheet
Scientific title	Prospective observational study on the prevalence and determinants of glucose intolerance in a Dutch caucasian population: the Hoorn Study
Study acronym	Hoorn study
Study objectives	The Hoorn study was initiated to study the prevalence and risk factors of impaired glucose metabolism and diabetes in an elderly Caucasian population. This initially cross-sectional study has been extended to a prospective cohort over the past decades, to study the risk factors for disturbances in glucose metabolism and complications associated with disturbances in glucose metabolism.
Ethics approval(s)	Ethics Review Committee of the VU University Medical Center Amsterdam, 27/06/1989, ref: 89/092
Health condition(s) or problem(s) studied	Impaired glucose metabolism and type 2 diabetes
Intervention	Between the years 1989 and 1992, a population-based survey of glucose tolerance was performed in the Dutch city of Hoorn in the West-Friesland region of the Netherlands. During this baseline measurement, information was obtained on, among others, glucose metabolism, diabetes-related risk factor levels and complaints, lifestyle, dietary intake, and demographic variables. Physical re-examinations, repeating the measurements at baseline with additional extensive measurement to assess diabetes complications, were conducted in 1990-1991, 1996-1998, 2000-2001, 2005-2007, and 2007-2009. All visits have corresponding measurements, including glucose metabolism determined by fasting plasma glucose, 75-g Oral Glucose Tolerance Test and HbA1c; anthropometrics; blood plasma lipid levels; albumin/creatinine ratio; blood pressure; family history of diabetes, self-reported medication use, disease history, diabetes-related complaints, lifestyle determinants and socio-economic status. Finally, in addition to physical follow-up visits, all participants are still actively followed up for vital status by linkage with the municipality register and for occurrence of cardiovascular disease, cancer and cause-specific mortality, by checking their medical records. In subsamples of the cohort, extensive physical diabetes complications have been measured, such as a retinopathy screening, autonomic function tests, peripheral neuropathy, ankle-arm pressure-ratio, echo-doppler scanning van de carotis and electrocardiography. In all visits additional measurements have been conducted, which vary from visit to visit.
Intervention type	Other
Primary outcome measure(s)	Disturbances in glucose metabolism, measured by fasting plasma glucose, 75-g Oral Glucose Tolerance Test and HbA1c at baseline and at the two follow-up measurements in 2010-2011 and 2013-2015
Key secondary outcome measure(s)	1. Depressive symptoms, measured using CES-D questionnaire at baseline and 7 year follow up 2. Quality of life, measured using questionnaires at baseline and 7 year follow up 3. Cardiovascular complications of diabetes, measured by a check of the medical records of the participants every 3 years
Completion date	01/01/2080

Eligibility

Participant type(s)	All
Age group	Senior
Sex	All
Target sample size at registration	2484
Key inclusion criteria	1. Men and women 2. Aged 50–75 years 3. Randomly selected from the municipal registry
Key exclusion criteria	Participants with a non-Caucasian background
Date of first enrolment	01/01/1989
Date of final enrolment	12/12/1992

Locations

Countries of recruitment

Netherlands

Study participating centre

Diabetes Zorgsysteem locatie Hoorn

Maelsonstraat 7
Hoorn
1624 NP
Netherlands

Results and Publications

Individual participant data (IPD) Intention to share	Yes
IPD sharing plan summary	Available on request
IPD sharing plan	The datasets generated during and/or analysed during the current study are/will be available upon request from Prof Joline Beulens (J.beulens@amsterdamumc.nl)

Study outputs

Output type	Details	Date created	Date added	Peer reviewed?	Patient-facing?
Participant information sheet	Participant information sheet	11/11/2025	11/11/2025	No	Yes

Editorial Notes

20/06/2025: Acronym added and study contacts updated.
12/07/2017: Internal edit.