The interaction of alcohol consumption and oral contraceptive use on lipids and lipoproteins

Abstract

Oral contraceptive (OC) use and alcohol consumption have been shown to alter the levels of lipids and lipoproteins in the blood. The effect of alcohol consumption on levels of total cholesterol, LDL cholesterol, HDL cholesterol, triglycerides, LDL-B, Apo-A1, the ratio of HDL cholesterol/total cholesterol, HDL cholesterol/LDL cholesterol, and the ratio of LDL cholesterol/LDL-B among normal healthy young women before initiation of oral contraceptives and after six months of oral contraceptive use are both described. Of primary interest is the mediating effect of alcohol consumption on the association between steroid usage and blood lipid values. At baseline, ethanol consumption was found to be positively associated with triglycerides, HDL-C, and Apo-A1 and negatively associated with LDL-C/LDL-B. After adjustment for several covariables, alcohol consumption was found to be positively associated with the increases in triglycerides and in Apo-A1 observed at 3 and 6 months after initiation of OCs. Since these two parameters are believed to have opposite relationships to cardiovascular disease, the effect of alcohol consumption remains uncertain.

PIP: The effects of alcohol consumption and oral contraceptive (OC) use on lipid and lipoprotein parameters were analyzed among 267 healthy women. Levels of cholesterol, low density lipoprotein (LDL)-B, triglycerides, LDL-cholesterol, and apolipoprotein A1 increased over the 6 months following OC initiation, while levels of high density lipoprotein (HDL)-cholesterol and the ratios HDL-cholesterol/LDL-cholesterol, HDL-cholesterol/cholesterol, and LDL-cholesterol/LDL-B tended to decrease with time. The greatest proportion of overall OC-related changes occurred between the baseline and 3-month measurement. Also observed was an association between baseline ethanol consumption and lipid parameters. Alcohol consumption was positively associated with triglycerides, HDL-cholesterol, and apolipoprotein A1 and negatively associated with LDL-cholesterol/LDL-B. After adjustment for several covariables, alcohol consumption was found to be positively associated with the increases in triglycerides and in apolipoprotein A1 observed at 3 and 6 months after initiation of OC use. The fact that apoliproprotein A1 levels increased with high levels of ethanol intake without a concurrent increase in HDL-cholesterol probably reflects substantial compositional changes in HDL. Overall, these findings suggest that women who initiate OC use can expect that the resulting increases in triglycerides and apolipoprotein A1 will be enhanced by baseline alcohol consumption. Since very high levels of triglycerides and low levels of apolipoprotein A1 are believed to be risk factors for cardiovascular disease, the net effect of alcohol consumption remains uncertain.