Doetinchem Cohort Study round 7

The development of health problems while ageing is the result of the lifelong
influence of genetics, lifestyle, biological risk factors and the environment.
In order to study the influence of lifestyle and other characteristics during
the different stages of life, representative long-term cohort studies are
needed with measurements aimed at the broad range of public health: lifestyle
(such as nutrition, physical activity, smoking) , risk factors (such as
overweight, hypertension, cholesterol), chronic conditions and quality of life.
The Doetinchem Cohort Study is an example of such a cohort.

The general objective of this study protocol is to add another follow-up
measurement, round 7, to the Doetinchem cohort study, 5 years after round 6,
and 30 years after round 1 This contributes to an infrastructure of data to
tackle research questions on the changes over the life course in life style,
health and disease and the relations between them.

The Doetinchem Cohort Study has been carried out for 30 years: data collection
in a random sample of men and women (residents of Doetinchem) originally
between 20-59 years. The study began in 1987-1991 and every 5 years
participants are examined. It takes 5 years to examine all participants, so it
is carried out at a continuous basis. The sixth round of data collection will
be completed this year (2018). After that, the data collection is continued
with a 7th round in the years 2018-2022, with the population being 50-90 years.
Throughout the measurement rounds, the willingness of the participants to be
re-examined is high with a 75-80% response.

Of the participants who have already participated in the study several times
and who did not want to quit, the following is asked: return a response card
for participation, to make an appointment for the physical exam, fill in
various questionnaires, come to the GGD location for a physical examination of
approximately 1.5 hours consisting of: measurements of height, weight, body
circumferences, cognitive function, blood pressure (arm and ankle),
quantitative ultrasound measurements of the calcaneus, AGES in the skin,
physical function (muscle strength, balance and chair test, usual gait speed)
blood and urine for various determinations (including cholesterol and glucose)
and storage for future scientific research. In addition participants are asked
to wear an accelerometer for a week. Subject to additional funding, the
following measurements are also added: collection of faeces.