Serum apolipoproteins, lipoproteins and fatty acids in relation to ischaemic heart disease in northern and southern European males.

Serum apolipoprotein and lipoprotein concentrations, fatty acid spectra of various lipids, dietary habits and common risk factors for ischaemic heart disease were studied in 73 and 77 randomly selected, 50-year-old healthy men in Naples and Stockholm, respectively. Mean serum cholesterol concentration was higher in Stockholm than in Naples men (6.23 vs. 5.47 mmol/l, p less than 0.001) as were low (LDL) (4.08 vs. 3.57 mmol/l, p less than 0.001) and high (HDL) (1.40 vs. 1.25 mmol/l, p less than 0.001) density lipoprotein fractions. Mean serum triglyceride concentrations did not differ. Mean apolipoprotein B and C-I concentrations were higher in Stockholm men (1,116 vs. 1,020 mg/l, p less than 0.05 and 96 vs. 79 mg/l, p less than 0.01, respectively). Stockholm men derived significantly more of their calories from fat (38 vs. 28%, p less than 0.001) and the dietary fat had significantly lower polyunsaturated-to-saturated fatty acid ratio (P/S-ratio 0.29 vs. 0.51, p less than 0.001), and less from carbohydrate (44 vs. 49%, p less than 0.001) than Naples men, respectively. Mean caloric intake and mean weight/height index did not differ. Stockholm men had higher blood pressures, but there were more smokers among Naples men. The higher fat intake in Stockholm men may offer an explanation of the differences seen in lipoprotein and apoprotein concentrations and compositions but other factors, such as genetic influences cannot be excluded. A greater cholesterol flux through the plasma compartment in Stockholm men may be one important factor contributing to the higher incidence of ischaemic heart disease in this population.