Physiologic and supraphysiologic increases in lipoprotein lipids and apoproteins in late pregnancy and postpartum. Possible markers for the diagnosis of "prelipemia".

Abstract

A supraphysiologic (greater than 95th percentile) rise in plasma lipids in pregnancy may serve as a marker for "prelipemia" in the same way that gestational diabetes is a marker for prediabetes. To qualify as prelipemic, subjects with an abnormal lipid rise antepartum must return to normal postpartum but may have other identifying characteristics. This paper describes the antepartum-postpartum changes of lipoprotein lipids and apoproteins at 34 to 38 weeks of gestation and 6 and 20 weeks postpartum in 23 subjects with physiologic and six subjects with supraphysiologic plasma lipid increases during pregnancy. These results are compared to measurements in 23 nonpregnant controls matched for weight, age, and race. In subjects with a physiologic antepartum lipid rise, postpartum total triglyceride and very low density lipoprotein (VLDL) lipids (cholesterol and triglyceride) and apo B returned to baseline within 6 weeks. In contrast, low density lipoprotein (LDL) showed a slow postpartum decline in lipids and apo B with elevations remaining at 20 weeks postpartum. High density lipoprotein (HDL) cholesterol concentrations, elevated in pregnancy, remained elevated at 6 weeks postpartum, but fell to baseline by 20 weeks postpartum. HDL triglyceride and apo A-l concentrations, both elevated in pregnancy, returned to baseline by 6 weeks postpartum. A supraphysiologic triglyceride rise in pregnancy was associated with a slower return of total triglycerides and VLDL to baseline, reduced HDL cholesterol ante- and postpartum, atypical changes in LDL cholesterol during pregnancy and postpartum, and evidence of hyperlipidemia among family members. Two subjects with hypercholesterolemia in the nonpregnant state showed no marked exaggeration of total or LDL cholesterol concentrations in pregnancy. The data support the hypothesis that a supraphysiologic rise in plasma triglyceride concentrations in late pregnancy may serve as a marker of prelipemia. Proof of the hypothesis requires further investigation and longer follow-up.