Menopause and breast cancer risk
Subtitle: the influence of dietary fat reduction and breast cancer risk factors on timing of menopause and change in mammographic density.
Published: 2005
Language: eng
Number of pages: 186
Description: Purpose. The primary goal of this research was to examine the effect of dietary fat reduction on two risk factors for breast cancer: timing of menopause and mammographic density. Mammographic density reflects the amount of stromal and epithelial tissue in the breast. A secondary goal was to examine the relationship of breast cancer risk factors with these outcomes. The research was carried out in the context of an ongoing clinical trial designed to test whether a low-fat, high-carbohydrate diet will reduce the incidence of breast cancer in women with extensive mammographic density.Results. There was no effect of the dietary intervention on time to menopause or change in mammographic density over menopause. Women who smoked or who were married had an earlier menopause than non-smokers and single women respectively. Greater number of children, higher weight, higher educational level, and past use of oral contraceptives were associated with later menopause. Greater height, past oral contraceptive use, and hormone replacement therapy were associated with a smaller reduction in mammographic density. Parity, greater insoluble fibre intake, weight gain, longer time between mammograms and higher baseline mammographic density were associated with a greater reduction in mammographic density.Conclusions. Intervention with a low-fat, high-carbohydrate diet did not affect the time to menopause or the change in mammographic density over menopause. All of the factors associated with change in mammographic density, except for change in body weight, were consistent in direction with their known, or suspected, effects on breast cancer risk. These factors may affect breast cancer risk, at least partially, through their effects on breast tissue composition. Further study on the mechanisms of these associations may lead to preventive strategies for breast cancer.Methods. Women were recruited from mammography units and randomized to a low-fat dietary intervention or control group (n=4,693). Women who were premenopausal at baseline were followed for the occurrence of menopause. Mammographic density was measured in baseline and postmenopause mammograms using a computer-assisted method. The effect of the intervention and other factors on time to menopause and change in mammographic density was assessed using survival analysis and multiple regression analysis respectively.
Notes: Source: Dissertation Abstracts International, Volume: 66-10, Section: B, page: 5329.

Thesis (Ph.D.)--University of Toronto, 2005.

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