LIPOPROTEIN(A) CONCENTRATIONS IN CORD AND CAPILLARY BLOOD FROM NEWBORNS AND IN SERUM FROM INPATIENT CHILDREN, ADOLESCENTS AND ADULTS

Investigations have been made upon the distribution of lipoprotein(a) concentrations in cord and capillary blood from newborns and in serum from in-patient children and adults. Full-term neonates (n = 123), chi ldren aged 1 month to 16 years (n = 331) and adults aged between 17 an d 88 years (n = 252) of age were included in the study. Lipoprotein(a) was determined using an immunoluminometric assay and a single lot of reagents. The assay had an effective measuring range of 1 - 800 mg/l. Lipoprotein(a) could be measured either in cord or capillary blood in the majority of cases. Problems arose in isolated cases, in each of wh ich there was a large concentration difference in lipoprotein(a) betwe en mother and child. The correlation data was: r = 0.897, n = 37, log (capillary blood) = 0.874 log (cord blood) + 0.165. The median lipopro tein(a) concentrations in cord and capillary blood were 13.9 and 10.2 mg/l respectively. Median lipoprotein(a) concentrations increased from birth up until the 6th decade (159 mg/l), decreasing to 95 mg/l durin g the 9th decade of life. In mature newborns, the median lipoprotein(a ) concentrations correlated with gestational age. The distribution of lipoprotein(a) concentrations in serum is skewed throughout life, the ratio mean/median being 2.07 at birth, 2.71 in children and 2.72 in ad ults. The percentage of children with lipoprotein(a) concentrations ab ove 250 mg/l was 23.0 (male) and 23.8 (female). The corresponding figu res for adults was 38.2 for males and 28.2 for females respectively. I n the group of newborns 27.7 percent had concentrations above 25 mg/l. There was no significant difference between median lipoprotein(a) con centrations after delivery in 80 healthy mothers aged 17-35 years (92. 5 mg/l) and 51 age matched in-patients (104 mg/l). Adult males had sig nificantly higher median serum lipoprotein(a) concentrations than adul t females (p < 0.05, males 144 mg/l, females 89 mg/l).