HAPTOGLOBIN POLYMORPHISM, A GENETIC RISK FACTOR IN CORONARY-ARTERY BYPASS-SURGERY

Haptoglobin (Hp) 2-2 type has been associated with accumulation of ath erosclerotic lesions in essential hypertension. The aim of this study was to investigate the relationship between Hp type and the extension of coronary lesions in 765 male patients who underwent coronary artery bypass grafting (CABG). In this group, relative Hpl (0.418) and Hp2 ( 0.582) allele frequencies were comparable with those of the reference population. Candidate CABG patients with a Hp 2-2 type were overrepres ented in the younger (< 45 years) age group (P < 0.05). Hp 2-2 patient s needed more bypass grafts than Hp 1-1 patients (relative risk 1.92, 95% C.I. 1.24-2.96). The Hp 2-2 type was overrepresented among victims of a previous acute myocardial infarction (P < 0.05), and among patie nts with a lower (< 45 years) age at infarction (P < 0.05). In patient s who already underwent a previous CABG, graft survival time was short est in Hp 2-2 type (P < 0.05). Patients with a Hp 2-2 type more likely develop atherosclerotic lesions despite comparable serum lipid concen trations. (C) 1997 Elsevier Science Ireland Ltd.