Thus, affected family members with familial hypertriglyceridaemia all have hypertriglyceridaemia, whereas affected individual from families with familial combined hyperlipidaemia may have hypercholesterolaemia alone, hypertriglyceridaemia alone, or elevations of cholesterol and triglyceride levels (Fig. 6.12). The lipoprotein pattern in individuals with familial combined hyperlipidaemia frequently changes.
While some individuals with familial hypertriglyceridaemia may be at increased risk of atherosclerosis, most do not appear to be so. Conversely, familial combined hyperlipidaemia markedly increases cardiovascular risk. Both disorders are probably heterogeneous but further classification must await a better understanding of their pathogenetic mechanisms.
