APO(A) PHENOTYPES AND LP(A) CONCENTRATIONS IN OFFSPRING OF MEN WITH AND WITHOUT MYOCARDIAL-INFARCTION - THE EARS STUDY

In the European Atherosclerosis Research Study, genetic and environmen tal markers of risk of premature coronary heart disease were compared in offspring of men with and without myocardial infarction before the age of 55 years. Cases were 682 students with a paternal history of my ocardial infarction, and control subjects were 1312 students without s uch a history. The students were enrolled in 14 universities in five E uropean regions (Finland, Great Britain, and northern, middle, and sou thern Europe). Lipoprotein(a) [Lp(a)] concentrations were skewed towar ds lower concentrations in both cases (median, 7.3 mg/dL; 95% confiden ce interval, 6.3 to 8.1 mg/dL) and control subjects (median, 6.6 mg/dL ; 95% confidence interval, 6.1 to 7.2 mg/dL) (P = .37). Significantly more northern European male cases than control subjects had Lp(a) leve ls exceeding 30 mg/dL (P = .040), but this did not pertain to females (P = .29), and overall, there was no difference between cases (16.5%) and control subjects (15.5%) in the frequency of Lp(a) concentrations above 30 mg/dL (P = .63). As expected, there was a significant (P < .0 1) inverse relationship between apo(a) molecular size and Lp(a) concen tration. In Great Britain there was a significant difference in phenot ype distribution between cases and control subjects (P = .035), due ma inly to a high frequency of the apo(a) S2 isoform in cases. A similar but statistically insignificant tendency was seen in northern European s. In the three other regions, however, the distribution of apo(a) phe notypes among cases and controls was similar: and in the study populat ion overall, the distribution of apo(a) phenotypes did not differ sign ificantly (P = .74) between cases and control subjects.