The New Hoorn Study, Prevalence and determinants of impaired glucose regulation
11 / 2005 - 05 / 2011
INTRODUCTION: In 1989, the Hoorn Study began investigating the prevalence of type 2 diabetes and impaired glucose tolerance in the general population of the Netherlands. Results showed that the prevalence of known and newly detected diabetes and impaired glucose tolerance in the 2484 participants was 3.6%, 4.8%, and 10.3%, respectively. Age, family history of diabetes, and waist:hip ratio were the most important determinants of glucose metabolism. Due to various lifestyle changes, the prevalence of diabetes type 2 has increased worldwide since 1989. In addition, a change in the phenotype of type 2 diabetes has occurred. Despite these changes, no large population study aimed at determining the prevalence of impaired glucose regulation and determinants of type 2 diabetes in the Netherlands has been carried out in the last 15 years. In addition, although beta-cell dysfunction is the key component of hyperglycaemia in the aetiology of type 2 diabetes, little is known about determinants of beta-cell function in the general adult population. OBJECTIVES: A. To determine prevalence and determinants of impaired glucose regulation. * To study the prevalence of impaired glucose metabolism and type 2 diabetes in the general population aged 40 65, and to compare these prevalence rates with the first Hoorn study. * To asses characteristics of impaired glucose metabolism (with special attention to lifestyle, percentage of body fat, and body composition). * To study differences in various indicators of cardiovascular disease between subgroups with a different glucose status. B. To study beta-cell function in the general population. * To study the distribution of insulin sensitivity and insulin secretion, as assessed by modelling of glucose and insulin concentration during a 75g oral glucose tolerance test in the general population. * To study the (cross-sectional) association between beta-cell function and impaired glucose tolerance. * To study various determinants of beta-cell function in the general population. C. To determine the prevalence of mood disorders, depression, anxiety, somatisation, and vague complaints. * To study (cross-sectional) associations between levels of mood disorder, depression, anxiety, somatisation, and vague complaints on the one hand and impaired glucose tolerance or autonomic nerve system balance on the other. METHODS: A random sample will be drawn from Hoorn s municipal registry: 3000 men and women, aged 40-65, 2100 of whom are expected to participate in the study. All participants will visit the Diabetes Research Centre in Hoorn , where the following tests will be performed: * A standard 75g oral glucose tolerance test to asses prevalence of impaired glucose regulation and beta-cell function. * A physical examination that includes anthropometry, blood pressure, heart rate variability (VU-AMS), measures of prevalent cardiovascular disease (IMT, ECG, ankle-arm index), determination of body fat (DXA, waist-to-hip ratio), and a morning urine sample (renal functioning). * Habitual physical activity, food consumption, smoking, alcohol intake, employment, education, current medication, disease history, family history of disease, depression, anxiety, and self-reported birth weight will be determined by questionnaires.