[Atherogenous mixed hyperlipidaemia with predominant slow pre-betalipoprotein overload: type IVb (author's transl)].

Together with the rare dysbetalipoproteinaemia (type III) and with combined beta- and pre-betalipoproteinaemia (type IIb), slow pre-betalipoproteinaemia (type IVb) belongs to the group of mixed hyperlipidaemias, where both blood cholesterol and triglycerides are raised. From a study of 30 patients, 10 of whom benefited from ultracentrifugal separation of lipoproteins, the authors define type IVb hyperlipidaemia, characterized by an equal increase in triglycerides and cholesterol and by the fact that the cholesterol overload is almost entirely due to slow pre-betalipoproteins. This particular type undoubtedly plays a part in the development of atherosclerosis.