The effect of peroral lynestrenol on serum lipids and lipoproteins in therapeutic amenorrhea of mentally retarded women.

Serum concentrations of total cholesterol, high-density lipoprotein cholesterol (HDL-C), apolipoprotein A1 (Apo A1), apolipoprotein B (Apo B), and triglyceride (TG) were measured and that of low density lipoprotein cholesterol (LDL-C) calculated in blood samples obtained from mentally handicapped women undergoing therapeutic amenorrhea (TA) induced by 5-10 mg of peroral lynestrenol, some receiving, some not receiving simultaneous anticonvulsant therapy (phenytoin, carbamazepine or barbiturate, alone or in combination). In addition, these analyses were carried out in women receiving only anti-convulsants and in controls (mentally handicapped women not receiving any of the above-mentioned medications). Significantly lower HDL-C, Apo A1, TG and cholesterol concentrations were measured in TA patients receiving lynestrenol only, than in those receiving anticonvulsants only, or in controls (p less than 0.001). With regard to HDL-C and Apo A1, patients receiving both lynestrenol and anticonvulsants were intermediate between lynestrenol only patients and controls, but the HDL-C/LDL-C and Apo A1/Apo B ratios were similar to those observed in lynestrenol only patients. Addition of 8 or 12 mg of estriol succinate to the lynestrenol regimen was virtually without an effect. However, halving of the lynestrenol dose resulted in a significant increase in HDL-C and in the HDL-C/LDL-C and Apo A1/Apo B ratios (p less than 0.001 or p less than 0.01), respectively. The lynestrenol dose was thus the most important determinant of lipoprotein pattern and should be kept as small as possible in order to reduce cardiovascular risk.