Impact of INsulin Sensitivity on Cardiovascular Risk Markers During 10-20 Years of FOllow up
Condition: Diabetes Mellitus; Hypertension; Ischemic Heart Disease; Stroke
MeSH terms: Heart Diseases; Myocardial Ischemia; Coronary Artery Disease; Diabetes Mellitus; Insulin Resistance
Study type: Observational

Summary: 
      The purpose of this study is to identify risk factors for insulin resistance and to
      investigate the influence of insulin sensitivity on development of cardiovascular risk
      markers like blood pressure, heart rate, body build (weight, BMI, waist-hip ratio, skinfold
      thickness), reduced insulin sensitivity, diabetes mellitus, dyslipidaemia, and
      sympathoadrenal activity or manifest cardiovascular disease among young men during 10-20
      years.
    

Detailed description: 
      In 1988 Reaven described a syndrome designed "syndrome X" based on the clustering of
      resistance to insulin-stimulated glucose uptake, hyperinsulinaemia, hyperglycaemia, increased
      triglycerides, decreased high-density lipoprotein (HDL) cholesterol and high blood pressure
      and proposed insulin resistance as the common feature and the aetiology of the syndrome.
      Later obesity and the sympathetic nervous system have been proposed as pathogenic factors of
      the metabolic syndrome, and still major controversy exists regarding its precise aetiology
      and different definitions of metabolic syndrome are also discussed.

      Insulin resistance is a growing epidemic concern in both industrialized and developing
      countries. It is one of the components of the metabolic syndrome, and plays an important role
      in the pathogenesis of type 2 diabetes. In view of the predicted increase in the number of
      diabetic patients during the coming decades, further information about risk factors and
      pathophysiology of diabetes are of utmost importance for early detection and possible
      prevention and early treatment from both a medical and a financial perspective. Our research
      group has for decades studied the pathophysiology of insulin resistance, hypertension,
      sympathoadrenal hyperreactivity and dyslipidaemia. We have also recently finished a long-term
      follow up study of subjects based on their cardiovascular and sympathetic responses to mental
      stress.

      During 1991-2002 healthy young men recruited from the military enlistments in the
      Oslo/Akershus area were examined at Center of Cardiovascular and Renal Research, Division of
      Medicine, Oslo University Hospital, Ullevål. Young, healthy men, mean age of 21, were
      examined using the hyperinsulinaemic isoglycaemic glucose clamp technique, which is the gold
      standard to assess insulin sensitivity. The present study aims to re-examine these subjects
      in order to investigate the influence of insulin sensitivity on development of cardiovascular
      risk factors and diabetes. We therefore have a unique opportunity to perform a true,
      long-term follow-up study of a homogenous sample of subjects of same race and gender which
      may provide new insights into various pathophysiological mechanisms in diabetes and
      cardiovascular disease including elucidating the connections between insulin resistance,
      changes in parameters of body build, blood pressure and sympathetic over-activity. Clarifying
      these mechanisms are of direct importance for the entire population. There has to our
      knowledge not been any previous long-term follow-up on subjects based on their insulin
      resistance measured with this gold standard technique.

      We now want to re-examine the same subject to investigate the influence of insulin
      sensitivity on development of cardiovascular risk factors like blood pressure, heart rate,
      body build (weight, BMI, waist-hip ration, skinfold thickness), reduced insulin sensitivity,
      diabetes mellitus, dyslipidaemia, and sympathoadrenal activity or manifest cardiovascular
      disease among young men during 10-20 years of follow-up.
    

Observational model: Cohort
Time perspective: Other
Sampling method: Non-Probability Sample
Study population: 
        103 men previously examined with hyperinsulinemic glucose clamp, measuring insulin
        sensitivity, at Center of Cardiovascular and Renal Research, Division of Medicine, Oslo
        University Hospital, Ullevål.
      
Biospecimen description: 
      whole blood, serum, white cells, urine, fat tissue cells
    
Keywords: Insulin resistance; Diabetes mellitus; Adipositas