Characters Of Body Fat Distribution In Early Postmenopausal Women And The Relations With Androgen Levels And Bone Mineral Density

BackgroundObesity is an important subject of postmenopausal research. It is usually observed that the morbidities of overweight and obesity increase after menopause. However, the domestic researches still lack systemic epidemiologic studies of the characters of body fat distribution in postmenopausal women. The effect of body fat distribution after menopause on bone mineral density is controversial. Resent studies have showed that there was a condition of "relative androgen excess" in menopausal transition. So we concluded that the androgen levels in menopausal period might have some relations with the changes of body fat distribution about menopause.ObjectIn the study, we designed to observe the levels of sex hormones and characters of body fat distribution in early postmenopausal women with normal weight and overweight or obese, then we investigated the relations between body fat distribution and androgen, bone mineral density and material metabolism, which could provide theoretical basis for the relevance between changes of androgen levels in menopause and metabolic syndrome.MethodHealth early postmenopausal women were chosen to be research subject, who were divided into two groups depending on whether the body mass index (BMI) was less than 24kg/m2. The two groups were named "normal weight group" and "overweight and obesity group", that each group had 36 persons. The research subject registered their basic information such as name, age and the latest menstruation. Each person's height, weight, waist, hip, blood pressure were measured, and dual x-ray absorptiometry (DEXA) was used to detect body fat distribution and bone mineral density (BMD). Every subject had fasted for 10-12 hours before we drawn their venous blood, and glucose, TC, TG, HDL-c, LDL-c, apoA-I, apoB, FSH, LH, E2, SHBG, T, DHEAS, E1, BGP and ADP were measured. We also calculated BMI, WHR, ratio of android and gynoid fat, ratio of trunk adiposity, T/L, apoA-I/apoB, FAI, E2/E1, and E2/T. SPSS 17.0 was used for statistic analysis.Results1. Comparisons of each index of research subject between the two groupsThe overweight and obesity group had higher levels of weight, BMI, waist, hip, and WHR. There were no differences in age and blood pressure between the two groups, but the time after menopause was longer in overweight and obesity group (P=0.014). DEXA results showed there were no differences in BMD of lumbar vertebra and hip joint between the two groups. The overweight and obesity group had much more amounts of total fat, total lean and fat percentage composition, but a similar amount of mineral materials to normal weight group, and a lower level of lean percentage composition (P<0.001). On the aspect of body fat distribution, the overweight and obesity group had higher levels of trunk fat, trunk fat percentage, ratio of trunk adiposity, T/L, and ratio of android fat, but the ratio of gynoid fat was on the contrary.The results of blood-lipoids metabolism showed apoA-I/apoB in the overweight and obesity group was observably higher than the normal weight group (P=0.003). And there were no differenced in other index of metabolism between the two groups.There were significant differences in E2/E1 (P=0.048), SHBG (P<0.001), and FAI (P=0.023) between the two groups. But in the levels of other sex hormones, BGP, and ADP, there were no differences.2. Single factor correlation analysis of body fat distribution in the two groupsIn normal weight group, there was significantly negative correlation between age and the degree of concentric fat distribution, while the amount of total fat had positive correlation to the time after menopause, and the amount of total lean had a significantly positive correlation to the BDM of lumbar vertebra and hip joint. And ratio of apoA-I/apoB in normal weight group had significantly negative correlation to the amount of total fat and the degree of concentric fat distribution. But the correlations above didn't exist in the other group.In normal weight group, there were no correlations between sex hormones and body fat distribution. In overweight and obesity group, only FAI showed significant correlation to body fat distribution.In both groups, the level of El had significantly positive correlation to the level of BGP. The level of ADP had significantly negative correlation to amount of fat and fat percent only in overweight and obesity group; and in normal weight group, the level of T had significantly negative correlation to the level of ADP.SummaryThere was a popular condition of fat excess accumulation in early postmenopausal women, and the type of body fat distribution was upper-body type, which was more observable in overweight and obese women. The higher levels of T/L and ratio of android fat, and lower apoA-I/apoB in overweight and obese early postmenopausal women, all showed that they had significantly higher risk of cardiovascular diseases than those with normal weight.The amount of total body fat and body fat distribution didn't have correlation to BMD. And in normal weight group, the BMD of lumbar vertebra and hip joint were dependent on the amount of total lean. Regardless of whether weight was normal, the level of E1 had positive correlation to the level of BGP. Because the early postmenopausal women with overweight or obesity had more amount of fat, the ratio of estrogen that was peripherally conversed was higher. So we concluded that the increase of amount of fat might be a risk factor of osteoporosis.The early postmenopausal women with overweight or obesity didn't have higher levels of estrogen, and the level of estrogen had no correlation to body fat distribution. However, the results that the level of SHBG in overweight and obesity group was significantly lower than in normal weight group, and the increase of FAI in this group, suggested that women with overweight and obesity had higher activity of androgen. And in overweight and obesity group, the increase of FAI had significant correlation to bad body fat distribution.In early postmenopausal women, ADP had significantly negative correlation to body fat accumulation only when overweight or obesity had already occurred. However, the increase of testosterone in early postmenopause might be an initial factor of the decrease of ADP.