Body fat distribution, the menopause transition, and hormone replacement therapy

Endocrine changes resulting from the menopause transition dramatically modify women's hormonal milieu. The consequences of these changes not only lead to cessation of reproduction and accompanying symptoms in women, but also dramatically impact long-term health. Loss of estrogen has been associated with the development of cardiovascular disease. Central distribution and accumulation of adipose tissue, and the concomitant insulin resistant dyslipidemic state have emerged as important components of a cluster of metabolic abnormalities that are strongly related to coronary heart disease. Thus, estrogen deficiency may affect cardiovascular disease risk by mediating changes in body fat distribution. This article is an update of the literature in the area of menopause, hormone replacement therapy, and body fat distribution. Cross-sectional studies using anthropometric measurements of abdominal fat distribution most often failed to detect an effect of the menopause transition that was independent of advancing age and degree of obesity. The use of radiologic techniques such as DEXA and computed tomography, however, led to the conclusion that the menopause transition accelerates the selective deposition of intra-abdominal fat. Available longitudinal data also support an increase in central body fatness occurring with menopause. Most intervention trials on hormone replacement therapy and body fat distribution showed that the treatment prevented the increase in central adiposity that was noted in postmenopausal women receiving no treatment or placebo. These results are supported by retrospective studies that showed a lower WHR in hormone users vs non-users. Mechanisms potentially explaining the menopause-related acceleration in abdominal fat accumulation include changes in regional adipose tissue metabolism in the face of a positive energy imbalance. As some inconsistencies were found among studies, further investigations using longitudinal and intervention designs, as well as more precise methodologies to measure body fat distribution, are needed to clearly establish the effects of menopause and hormone replacement on abdominal body fat distribution and the concomitant increase in cardiovascular disease risk.