LPA and myocardial infarction: Due to small numbers of children with a history of heart attack within ethnic groups, the difference in percentage of persons with Lp(a) did not attain significance in within-groups analysis: white children, 42.56% versus 18.36%, P = 0.23, black children 72.37% versus 54.06%, P = 0.12, Mexican American children 34.46% versus 18.26%, P = 0.33 (Table 2).