Coronary risk factors and metabolic disorders in first-degree relatives of normocholesterolaemic patients with premature atherosclerosis

Aims: Despite agreement on the need for screening for the presence of cardiovascular risk factors in first-degree family members of patients with premature coronary artery disease (CAD), this is not routinely carried out in relatives of normocholesterolaemic patients. We evaluated cardiovascular risk factors in family members of normocholesterolaemic patients with premature CAD.

Methods: Eligible index subjects were patients with premature CAD (<55 years in men and <65 years in women), who had undergone percutaneous transluminal coronary angioplasty. Patients with fasting total cholesterol levels >6.5 mmol/l were excluded. Sixteen index subjects were included with a mean age of 49±8 years and total cholesterol levels of 5.5±0.8 mmol/l. Sixty-four first-degree relatives from these 16 pedigrees were screened, namely 18 children, 42 siblings and four parents. National Cholesterol Education Program III guidelines were used to identify candidates for lipid-lowering treatment. Furthermore, the presence of four additional metabolic disorders was investigated: the metabolic syndrome, increased levels of lipoprotein(a) (Lp(a)), hyperhomocysteinaemia and postprandial hyperlipidaemia.

Results: Of 64 relatives free of CAD, 34 subjects (53%) fulfilled the criteria to receive therapeutic advice, 20 of whom (31% of the relatives) were candidates for drug therapy. Sixty-one relatives were available for a full assessment of metabolic disorders and in 37 relatives (61%) at least one metabolic abnormality was present. Twelve subjects had hyper-Lp(a), seven subjects had postprandial hyperlipidaemia and two had the metabolic syndrome. Furthermore, 16 subjects had a combination of at least two out of four metabolic disorders.

Conclusion: Careful evaluation of coronary risk factors and metabolic variables in first-degree relatives of normocholesterolaemic CAD patients identifies a significant number of subjects at increased coronary risk in whom primary prevention measures should be initiated.