Impairment of the Lipid Metabolism in Newborns in the Early Neonatal Period

Abstract

The purpose of the study. To study parameters of the lipid metabolism in newborn infants to identify general patterns depending on the gestational age.Materials and methods. The course of pregnancy and its outcome was analyzed in 286 women who gave birth to 323 infants; 89 of them were born in multiple pregnancies. The infants were divided into 4 groups depending on the gestational age. Levels of cholesterol (C), triglycerides (TG), low-density lipoproteins (LDL) and high-density lipoproteins (HDL) were tested in the central venous blood immediately after birth and on the 5th day of life.Results. Hypotriglyceridemia below 0.2 mmol/l was typical for 31.3% of the newborns; a TG level within the range of 0.21—0.5 mmol/l was found in 43.3% of infants, i.e. the perinatal production of TG was decreased in 76.6% of infants. The perinatal TG production depended on the infant's gestational age: the smaller it was, the lower TG blood level was in infants at birth. At the gestational age of 25—33 weeks, the perinatal TG production was low in most newborns. The perinatal production of the lipid metabolism parameter was increased with the increase of the gestational age. The TG blood level increased rapidly at the gestational age of 37 weeks. The postnatal TG production in the blood of newborn babies had no dependence on the gestational age strating from the gestational age of 31 weeks and more. Hypercholesterolemia and lower both LDL and HDL levels were found in newborns of all groups at birth; no significant intergroup differences in concentration of C, HDL or LDL were observed (P>0.01).Conclusion. The state of the lipid metabolism in the newborns in the perinatal period depends on the gestational age and the birth weight. Low TG production is typical for small premature infants with a low and extremely low birth weight due to physiological immaturity of organs and systems. The peculiarities of the prenatal morphogenesis make an adequate lipid metabolism possible by the full-term gestational age only. An abnormal course of pregnancy impairs normal triglyceride, C, LDL and HDL production. The greatest changes of the tested parameters are typical for small immature infants with a gestational age of 25—31 weeks. This age is associated with a high incidence of the respiratory distress syndrome. Deficiency of buffer bases affects the TG production at birth; the pH value and blood oxygen tension at birth affect the C level. The production of lipid metabolism parameters increases with the increase of the gestational age. There are certain individual characteristics in newborns who may have perinatal disorders of the lipid metabolism at the full-term gestational age.

Keywords

• newborns
• gestational age
• triglycerides
• cholesterol
• low- and high-density lipids