CALGARY -- Breast cancer rates among women are on the rise, but new research has uncovered trends that could help target prevention measures to improve the situation.

A new study published in The Lancet Global Health looked at cancer rates in women from 41 countries.

According to the findings, there are significant increases in premenopausal breast cancer rates in countries worldwide, including Canada.

Postmenopausal breast cancer is increasing more rapidly in lower-income countries. This is likely related to developing countries adapting behaviours more common in westernized countries.

"To our knowledge, this is the first study to investigate the global rates and trends of pre- and postmenopausal breast cancer," said Dr. Miranda Fidler-Benaoudia, Ph.D., studies led researcher and member of the O'Brien Institute for Public Health at the Cumming School of Medicine.

"Distinguishing between pre- and postmenopausal breast cancer allowed us to uncover different trends, which could be important for tailoring prevention efforts and curbing the future breast cancer burden worldwide," she continued. "Although the study provides evidence of an increase in breast cancer rates in women of all ages, the increase in premenopausal breast cancer in higher-income countries is particularly concerning."

From what she studied, premenopausal breast cancer was significantly increasing in 20 out of 44 populations, each representing a country or an ethnic group.

"The risk of developing cancer increases as a woman ages," Fidler-Benaoudia said.

"The increasing rates of postmenopausal breast cancer in lower-income countries highlights opportunities for prevention," says Dr. Hyuna Sung, Ph.D., a cancer epidemiologist with the American Cancer Society, and study co-author.

"We know several well-established risk factors are modifiable, including excess body weight and physical inactivity, which is encouraging for prevention efforts."

This study highlights the inequalities in cancer mortality worldwide, showing that 47 per cent of women diagnosed with premenopausal breast cancer in less developed countries will die, compared to only 11 per cent in developed countries.

"Early diagnosis and access to treatment remain key to combating breast cancer in low- and middle-income countries, and that prevention efforts to decrease exposure to known risk factors for the disease must be increased globally," Fidler-Benaoudia said. "The findings from this study shows important differences in the breast cancer burden by age and point to the need for prevention initiatives such as efforts to reduce obesity and alcohol consumption, increase physical activity and breastfeeding—all of which reduce one’s risk for developing breast cancer."