Obesity Linked to Increased Breast Cancer Rates in Hispanic Women
Average weight gain was dramatic in the last decade
FRIDAY, Aug. 16, 2002 (HealthDayNews) -- Obesity may be a contributing factor to increasing cases of breast cancer among Hispanic women.
While Hispanic women have been known to be at lower risk than most other women for developing breast cancer, the rates are climbing, according to a study in the August issue of the Annals of Epidemiology. The increasing risk of breast cancer for Hispanic women before and after menopause may be due to the weight they gain in adulthood and their percentage of body fat, the research suggests.
It was done by scientists from the University of Southern California (USC), the University of New Mexico and Johns Hopkins University.
This is the first study to examine the relationship between weight and breast cancer risk in Hispanic women.
"We know that breast cancer incidence and mortality have been rising in Hispanic women, but no one knows why," lead investigator Dr. Frank D. Gilliland, assistant professor of medicine, USC's Keck School of Medicine, says in a statement.
"The thought was that perhaps these women were starting to have fewer children, have having them later in life, which may increase risk. But we looked at all the major reproductive factors, and they explained only 5 percent of the increase in risk. Something else must be going on," Gilliland adds.
The study included more than 1,500 Hispanic and non-Hispanic white women with breast cancer in New Mexico in the early 1990s. The researchers collected information about the women's current weight, their weight at age 18, menopausal status and use of hormone replacement therapy.
They found that obese Hispanic women had nearly twice the risk of breast cancer, and that risk was greater regardless of whether they had gone through menopause. Obese non-Hispanic white women had increased breast cancer risk only after menopause.
Hispanic women whose weight at the time of the study was more than 30 pounds heavier than their weight at age 18 more than doubled their risk of breast cancer.
The study also found that breast cancers linked to weight gain in Hispanic women and post-menopausal non-Hispanic white women mostly were estrogen- and progesterone-receptor positive. Also, breast cancer risk was higher in women who never used estrogen and who gained the most weight.
Obesity in Hispanic women increased 80 percent from 1991 to 1998, the study says, with about 25 percent of that population being classified as obese.
Weight gain among Hispanic women also poses a risk for polycystic ovarian syndrome, as this article from Columbia University indicates.