IJsselstein Study of Central Obesity

In 2004 the Health Council of the Netherlands suggested targeted screening for
various cardiovascular risk factors in a high-risk group of obese subjects,
instead of a general population-based screening for type 2 diabetes.
Such a screening was the IJSCO study (IJsselstein Screening for Central Obesity
to detect metabolic syndrome), which aimed to detect metabolic syndrome
patients. All patients of the 'Medische Maatschap IJsselstein' aged 20-70 years
who were not known with diabetes, hypertension or dyslipidemia were asked to
measure their waist circumference. 1721 people with a self-measured increased
waist circumference were invited for further research. In 473 the metabolic
syndrome was detected. Halve of the detected cases was between 30 and 50 years
old. In this agegroup, people visit their general practitioner less often. This
makes screening even more relevant. The metabolic syndrome prevalence among all
people aged 20-70 years in IJsselstein was 15.5%.

Screening participants were asked to contact their general practice three weeks
after the screening for their results. They were treated according to the
guidelines of the Dutch College of General Practitioners.

Following the participants three more years will enable us to get a better
overview of the consequences of the screening with regard to treatment, health,
lifestyle modifications and illness perception with regard to obesity.

Primary Objective:
• To assess the remission of the metabolic syndrome following standard care
about three years after screening in people with screen-detected metabolic
syndrome, and to assess which determinants at the time of diagnosis predict
remission of screen-detected metabolic syndrome within three years following
usual care.

Secondary Objectives:
• To assess how the health status developed with regard to waist circumference,
body mass index (BMI), blood pressure, fasting glucose and lipid spectrum in
patients with central obesity that were screened for the metabolic syndrome;
• To assess how many patients developed diabetes mellitus or cardiovascular
disease
• To assess which cardiovascular medications were prescribed to patients with
screen-detected metabolic syndrome;
• To assess how lifestyle changed over a three years follow-up period in
patients with central obesity with and without the metabolic syndrome;
• To identify those patients who are likely not to adhere to suggested
preventive measures with regard to their lifestyle after they were diagnosed
with the metabolic syndrome;
• To assess illness perception with regard to obesity in patients with central
obesity with and without the metabolic syndrome.

Observational study.
All screening participants that were detected with the metabolic syndrome will
be invited for further research. As a control group, we will also invite a
random sample of the participants with central obesity that did not meet the
metabolic syndrome criteria. Investigations will include a short physical
examination, blood collection and a questionnaire.

The burden associated with the study for the patient is minimal: one visit and
one venapuncture. The only risk is possibly a small hematoma at the
venapuncture site. The possible benefit for the patient is the reduction of
cardiovascular risk by treatment of the detected cardiovascular risk factors.