THE INDEPENDENT EFFECTS OF HYPERANDROGENAEMIA, HYPERINSULINAEMIA, AND OBESITY ON LIPID AND LIPOPROTEIN PROFILES IN WOMEN*

Abstract

We performed this study to clarify the independent effects of hyperandrogenaemia, hyperinsulinaemia, and obesity on lipid and lipoprotein levels in women with hyperandrogenaemia (HA) and anovulation which we designated as the polycystic ovary syndrome (PCO). We examined fasting lipid, lipoprotein, sex hormone and insulin levels in 38 women (21 obese (ob), 17 non-obese (nob) with HA and anovulation (PCO) and 38 normal ovulatory women (21 obese, 17 non-obese), matched for age and weight. The women with PCO had significantly increased androgen levels compared to the normal women. However, total oestradiol levels were similar in the PCO and normal women. Mean fasting insulin levels and 2-h glucose levels (both P < 0.001) were significantly higher in ob PCO women. There were significant decreases (P|Ml0.01) in high-density lipoprotein (HDL) levels in both the obese groups (ob PCO and ob normal) compared to the non-obese (nob PCO and nob normal) groups. Otherwise, mean lipid and lipoprotein levels did not differ in the ob or the nob PCO women compared to the control groups. The correlations between sex hormone, lipid and lipoprotein levels differed in the four groups of women. After statistical adjustment for potential hormonal interactions, nob PCO women had significant positive correlations between testosterone and LDL levels (R=0.51, P < 0.05) and insulin and TTG levels (R. 0.61, P < 0.01). Ob normal women had a significant positive correlation between oestrone and TTG levels (R=0.44, P|Ml0.05). We conclude that (1) PCO women are in a low to intermediate risk group for cardiovascular disease based on their lipid and lipoprotein profiles; (2) obesity, but neither hyperandrogenaemia nor hyperinsulinaemia, was associated with significant decreases in HDL levels and was therefore the major factor affecting lipid profiles in PCO; (3) a significant relationship existed between androgen and lipoprotein levels only in nob PCO women, suggesting that the mechanisms underlying these associations are complex.