FASTING AND POSTPRANDIAL LIPID ABNORMALITIES IN HYPOPITUITARY WOMEN RECEIVING CONVENTIONAL REPLACEMENT THERAPY

Hypopituitary patients, particularly women, have excess mortality, mos tly due to vascular disease. We have studied circulating lipid and lip oprotein concentrations, fasting and over 24 h, in hypopituitary women and men and in matched controls. Firstly, 67 hypopituitary patients ( 36 women) and 87 normal controls (54 women) were studied after an over night fast. Secondly, 12 patients (6 women) and 14 matched controls (7 women) were studied over 24 h of normal meals and activity. The patie nts were all GH deficient and were replaced with cortisol, T-4, and se x hormones where appropriate, but not with GH. In the first study, cir culating triglycerides, total cholesterol, high density lipoprotein (H DL) cholesterol, and low density lipoprotein (LDL) cholesterol were me asured after an overnight fast. In the second study, fasting levels of apolipoprotein B, apolipoprotein Al, and lipoprotein(a) were also mea sured, and then circulating triglyceride and total cholesterol concent rations were measured over 24 h. Fasting concentrations of triglycerid e (mean +/- SEM, 1.73 +/- 0.22 vs. 1.11 +/- 0.09 mmol/L; P = 0.0025), total cholesterol(6.45 +/- 0.25 us. 5.59 +/- 0.21 mol/L; P = 0.002), L DL cholesterol (4.58 +/- 0.24 us. 3.80 +/- 0.19 mmol/L; P = 0.007), an d apolipoprotein B (135 +/- 10 vs. 111 +/- 9 mg/dL; P = 0.048) were el evated in hypopituitary compared to control women. The lipid alteratio ns were observed in older and younger women and occurred independently of sex hormone or glucocorticoid replacement. Fasting values were not significantly different in hypopituitary and control men. Patients an d controls (women and men) had similar fasting HDL cholesterol, apolip oprotein Al, and lipoprotein(a) concentrations. Although the differenc es that existed in fasting lipid values were most marked in women, the men were also abnormal in this respect, in that a higher proportion o f hypopituitary than control men had total and LDL cholesterol above r ecommended values (greater than or equal to 6.2 and greater than or eq ual to 4.1 mmol/L, respectively). In the postprandial period (0730-203 0 h), the areas under the curve (AUG) for circulating triglyceride and total cholesterol were significantly higher in hypopituitary than con trol women (P = 0.0089 and P = 0.0016, respectively). The AUC for trig lyceride and total cholesterol over 24 h were also significantly incre ased (P = 0.009 and P = 0.0004, respectively). No significant differen ces were observed for postprandial and 24-h AUC for triglyceride and t otal cholesterol concentrations in men. We conclude that hypopituitari sm with conventional replacement therapy is associated with unfavorabl e Easting and postprandial lipid and lipoprotein concentrations, parti cularly in women. The changes may contribute to the observed increased vascular morbidity and mortality.