(Apo)lipoprotein(a) concentrations at birth and in the first days and months of life--studies on the distribution of serum levels and the predictive value of measurements made at this time.

This study was carried out on 625 newborns delivered between July 1993 and December 1994 and 221 children visiting the clinic in the first year of life using an immunoluminometric assay specific for apolipoprotein(a), but calibrated with lipoprotein(a), hence the use of the term (apo)lipoprotein(a) for neonatal values. (Apo)lipoprotein(a) concentrations were measured in 278 neonates over the first 12 days of life (median observation time 6 days). A further 64 children were followed up over a period of 1-10 months (median observation time 5 months). The median (apo)lipoprotein(a) concentration at birth was 14.7 mg/l (males 14.6, females 14.7 mg/l). The range of concentrations measured was between 1 and 433 mg/l. The correlation coefficient between maternal and neonatal lipoprotein(a) at birth was 0.509 for 483 data pairs. The behaviour of serum concentrations of (apo)lipoprotein(a) during the first days of life varied greatly and was independent of the birth level. Eighty-four babies showed a decrease, 107 an increase and 87 no change in (apo)lipoprotein(a) levels; over the first months of life was more unified with 50 children showing an increase in serum lipoprotein(a), a decrease in 4 cases and no change in 10 cases. In these 64 children the median increase in serum (apo)lipoprotein(a) was from 15.8 mg/l at birth (range 1 to 364 mg/l) to 38.5 mg/l at 6 months. The median lipoprotein(a) concentrations in the children under 1 year (median age 6 months) was 37.0 mg/l (males 37.1, females 37.0 mg/l).(ABSTRACT TRUNCATED AT 250 WORDS)