IS MILD HYPERTRIGLYCERIDEMIA ONE TIP OF T HE ICEBERG OF INSULIN-RESISTANCE

Cardiovascular patients often present with several risk factors; the c lustering of hyperlipemia, hypertension, obesity and glucose intoleran ce is called the >>metabolic syndrome<< and resistance to insulin stim ulated glucose uptake is thought to play a major role. Therefore, in a hypertensive patient, hyperlipemia could point at the presence of thi s syndrome; most often, however, moderate hypertriglyceridemia (hTG) i s not considered to be a risk factor, especially as some intervention studies did not define TG as an indipendent risk factor. In the presen t investigation, we looked at the risk profile of hypertensive patient s with mildly elevated TG (150-230 mg%) and a normal glucose loading t est; venous insulin levels were determined during the test (Enzyme Imm uno-Assay, Boehringer Mannheim, Germany). Twenty seven patients were c ompared with seventeen healthy volunteers. The risk patients, although showing lipids and glucose tolerance within the normal range, had a s ignificantly increased atherogenic risk profile, when compared to the controls, with raised levels of total-cholesterol (237 vs 202 mmg%, = p less-than-or-equal-to 0.05), LDL-C (125 vs 147 mg%), triglyceride s (179 vs 111 mg%) and lower HDL-C (43 vs 58 mg%*). Plasma glucose wa s significantly higher at all intervals (0-60-120 min) and insulin lev els were almost doubled at 60 (116 vs 60 uU/ml) and 120 minutes (92 v s 36 uU/ml). The latter finding reveals a drastic decrease in periphe ral insulin-stimulated glucose uptake in the risk group, most probably caused by insulinresistance. Due to the >>normal<< laboratory values, these patients would not have been considered to be at increased card iovascular risk. The additional determination of insulin during an ora l glucose load was able to unmask the impaired insulin sensitivity. Th us, in the hypertensive patient the dangerous Metabolic Syndrome is de tectable via the marginally elevated triglycerides.