Coronary Artery Disease in 116 Kindred with Familial Type II Hyperlipoproteinemia

Analysis of cardiovascular status in adult relatives of 116 kindred affected with familial hyperbetalipoproteinemia (type II hyperlipoproteinemia) was carried out to assess coronary artery disease (CAD) risk in relatives with type II (II) compared to unaffected family members. Over 90% of the 738 living relatives were interviewed by one investigator and 12 lead electrocardiograms were obtained. In these, and in 285 deceased relatives, physician and hospital records were utilized to determine CAD events by standard criteria. This study, the largest of its kind, permitted more precise and extensive determination of the CAD risk accompanying severe hyperbetalipoproteinemia than has heretofore been possible. CAD was diagnosed in 29.5% of II's compared with 10.5% of normal relatives (N) ( P < .001). The II's and N's did not differ significantly with regard to age distribution, sex, hypertension, smoking habits, or body mass index. According to the Rose questionnaire, angina pectoris was diagnosed in 21.8% of II's and 6.5% of N's ( P < .001). Documented myocardial infarction occurred in 6% of II's versus 1% of N's ( P = .002). CAD death or myocardial infarction occurred in 10.1% of II's compared with 1.8% of N's ( P < .001). The cumulative probability of nonfatal or fatal CAD by age 40 in male II's was 16% (1 in 6); by age 60, the expectation of an event had risen to 52% (1 in 2). Among male N's, the risk of nonfatal or fatal CAD by age 60 was 12.7%, lagging 20 years behind that seen in male II's. In female II's, the risk of nonfatal or fatal CAD by age 60 was 32.8% compared with only 9.1% in female N's.