Mixed hyperlipemia, a sixth type of hyperlipoproteinemia

Abstract

A study of 132 hyperlipidemic patients that included dietary treatment of 81 for 1 to 10 years was reviewed to examine the thesis that mixed hyperlipemia, now called type II B, should be classified as type VI. Serum lipids in type VI had an elevated beta or low density lipoprotein level characteristic of type II and an elevated pre-beta or very low density lipoprotein level characteristic of type IV, yet all lipid levels were relatively moderate in elevation and normal in proportion. Type VI was present in 32 % of these hyperlipidemic patients and was closely associated with atherosclerotic vascular disease. Unlike type II, serum beta lipoprotein and cholesterol in type VI were reduced to relatively normal levels with a polyunsaturated-fat diet; unlike type IV, serum pre-beta and triglycerides were reduced to normal levels with diet. Triglyceride and pre-beta lipoprotein levels were increased with high dietary carbohydrate so that the polyunsaturated-fat diet with moderate amounts of carbohydrate was more effective in maintaining reduced serum lipid levels than the low-fat (high carbohydrate) diet. Because of these distinctive characteristics, mixed hyperlipemia or type II B should be classified as type VI.