[Serum lipoproteins and coronary disease in diabetes. Changes in the lipoprotein pattern in relation to the type of antidiabetic therapy]. / Lipoproteine sieriche e malattia coronarica nel diabete. Modificazione del quadro lipoproteico in relazione al tipo della terapia antidiabetica.

One hundred and fifty seven maturity-onset diabetics (77 males and 80 females) with coronary heart disease (CHD) were compared with 130 non-CHD diabetic patients (62 males and 68 females) of the same age-range. Integrated mean blood pressure, duration of diabetes, serum triglycerides, beta and prebeta-lipoproteins were significantly higher and alpha lipoproteins significantly lower in CHD than in non-CHD patients. Alpha lipoproteins, duration of diabetes and beta lipoproteins were the variables of highest weight in discriminating CHD from non-CHD patients. Alpha lipoprotein had a greater discriminating power than beta lipoprotein in man, while in women the opposite occurred. In patients on insulin and on sulfonylurea therapy, both with and without CHD, the concentration of alpha lipoproteins, but not of other lipoproteins, was higher than in the corresponding subgroups of the diet-treated patients. However, within each treatment group, patients with CHD had lower alpha lipoproteins.

Serum lipoproteins in diabetes: relation of alpha-lipoprotein level to therapy.

Three hundred and sixty diabetic patients (125 on insulin, 109 on sulfonylureas and 126 on diet alone) were selected to investigate the effect of the type of treatment and of the degree of metabolic control on serum lipoproteins. Prebeta-lipoprotein concentration was higher than normal in all treatment groups. Beta-lipoproteins were significantly higher in diabetic women than in controls. No difference in beta- and prebeta-lipoprotein concentration existed between the 3 treatment groups. Alpha-lipoproteins were significantly higher in insulin-treated than in diet-treated patients irrespective of the degree of metabolic control. The daily dose of insulin and, in patients on diet or sulfonylureas, serum IRI were positively correlated to alpha-lipoprotein concentration while this lipoprotein fraction was not significantly correlated to fasting blood sugar. Alpha-lipoprotein concentration, then, appears to be markedly influenced by exogenous and endogenous insulin, independently of the degree of metabolic control.

An evaluation of quantitative agarose-gel electrophoresis of serum lipoproteins.

The method of Hatch et al. (Hatch, F.T., Lindgren, F.T., Adamson, G.L., Jensen, L.C. and Wong, A.W. (1973) J. Lab. Clin. Med. 81, 946-960) of quantitative determination of serum lipoproteins has been compared with preparative ultracentrifugation and chemical analysis of the lipoprotein fractions and a good concordance was demonstrated. The replacement of the coefficients proposed by Hatch et al. by the ones derived from the present study does not bring about relevant changes of the results when the harmonic mean of two calibration factors, derived from serum cholesterol and triglycerides, is used, thus indicating that this method of calculation minimizes the effect of variation of the chemical composition of lipoproteins. The method is sufficiently reliable and reproducible for practical pruposes and is recommended as the standard method for the clinical laboratory.