Health and lifestyle in the Netherlands

For health policy development, up to date figures are needed on the prevalence
of risk factors and chronic diseases. For many years, no representative
measured data are available for e.g. bodyweight and blood pressure levels in
the Dutch population. The Ministry of Health funded this study to obtain these
data.

The objective of the study is to estimate the prevalence of (abdominal)
overweight/obesitas, metabolic syndrome (and its components), and undiagnosed
diabetes in the Dutch population, aged 30-69 years. Besides, differences in
lifestyle (smoking and exercising) and health for people with and without
overweight will be determined. Further, we anticipate future research questions
in the field of lifestyle, risk factors and chronic diseases that can be
studied with the data gathered.

The study will be conducted among 1.500 persons in two municipalities in the
Netherlands. In each municipality a random sample of men and women aged 30-69
years is selected from the municipal population register (GBA, Gemeentelijke
Basisadministratie). Persons receive a questionnaire at their home address (on
background variables, chronic diseases and lifestyle) and are invited for a
physical examination in a research centre in their neighborhood. Persons who
don*t respond to the advance letter are invited at their homes. If persons
agree, their height and weight are measured at their homes. Preferably, people
have fasted if the physical examination at the research centre takes place in
the morning. The examination consists of the following measurements: height,
weight, waist- and hip circumference and blood pressure. Besides, blood is
collected to determine the levels of total and HDL cholesterol, triglycerides,
HbA1c and creatinine. During blood collection a question on use of dietary
supplements is posed. A small amount of blood, in different fractions, is
stored for further research, for example to determine the dietary status (for
example folic acid, iron and vitamin D). Furthermore, a non-response study will
be conducted.

Amendment 14.Dec.2010
A selection of the study population, 650 persons, will be asked to participate
in a second blood draw and completion of a questionnaire on use of vitamines,
minerals and other food supplements. The second blood draw (2 ml) will be used
to assess the status of vitamin D after the winter season. Only participants
that did have a blood draw already and who gave consent to be invited again,
will be invited for this.

Persons are asked to complete a questionnaire and to participate in a physical
examination at a site in their neighborhood. If the examination takes place in
the morning, the participants preferably have fasted. The duration of the
physical examination is about half an hour. During the examination height,
weight, waist and hip circumference and blood pressure will be measured. In
addition, blood is collected to determine the levels of cholesterol,
triglycerides, glucose, HbA1c and creatinine.

Amendment 14.Dec.2010
The participants will be asked to fill out a questionnaire on vitamine and
mineral use at home (5 minutes). Those who agree to participate have several
options on datedate and time (depending on the location) to visit the site for
the blood draw. The visit for blood draw and handing over the questionnaire
will take about 10 minutes.