[The metabolic syndrome, its heredity, methods of detection and clinical significance].

BACKGROUND: The metabolic syndrome is a common denominator of a number of risk factors which are associated with type 2 diabetes and serious cardiovascular complications. The symptoms develop on the background of insulin resistance and are associated with hyperinsulinism. They are not manifestations of ageing, but are developing probably on a predisposed background already in young age.

METHODS AND RESULTS: In the families of 39 probands with symptoms of the metabolic syndrome (MS) there were 58 offspring, mean age. 26.4 +/- 8.7 years. They were compared with 46 controls matched for age, BMI and sex without a family-history of metabolic diseases. The offspring from the families of probands with MS differed in particular by a lower HDL cholesterol level (1.38 mmol/l +/- 0.31 vs. 1.72 mmol/l 1-0.53, p < 0.001), a higher blood sugar level during the glucose tolerance test (p < 0.01) and a higher level of apolipoprotein B (Apo B, p < 0.01). The stimulated insulin concentration, the IRI sums were highly significantly raised (S IRI 240.9 microU/ml +/- 141 microU/ml vs. 177.1 microU/ml +/- 77.9 microU/ml, p < 0.01), similarly as the C peptide concentrations (S C peptide 7.61 pmol/ml +/- 2.84 pmol/ml vs. 5.02 pmol/ml +/- 1.49 pmol/ml, p < 0.001) which correlated mutually. The great majority of offspring came from parents with hypertension and hyperlipoproteinaemia resp., the rest from diabetic families and families with IHD. In offspring of families of hypertonics there was a lower ratio of linoleic acid in serum phospholipids, contrary to complement (= the other members of the group), in offspring of subjects with hyperlipoproteinaemia there were higher fibrinogen and uric acid levels. The offspring of diabetics had higher mean BMI values, in families of patients with myocardial infarction higher C peptide levels were found.

CONCLUSIONS: Already at post-adolescent age there are convincing signs which suggest the possible development of metabolic syndrome in predisposed families, as ensues from a comparison with controls: raised IRI, C peptide and some MS component levels. Linoleic acid as well as fibrinogen, BMI and C peptide concentrations which differed in offspring with different types of family-history from the complement are also related directly or indirectly with hyperinsulinaemia.