Stress may increase the risk of breast cancer

NEW YORK (Reuters Health) - The results of a new study support an interaction between severe life events, psychological distress, and breast cancer. The findings appear in the online BioMed Central journal BMC Cancer.

"Young women who are exposed to severe life events more than once should be considered as a risk group for breast cancer and treated accordingly," first author Dr. Ronit Peled said in a telephone interview with Reuters Health.

Peled, from Ben-Gurion University of the Negev, Beer Sheva, Israel, and colleagues studied 255 women younger than 45 years old who had been diagnosed with breast cancer, and compared them with 367 healthy women of a similar age.

The team evaluated interactions between breast cancer and severe life events -- such as the loss of a parent, close relative or spouse, or the divorce of parents before age 20 -- and mild to moderate life events -- e.g., separation from a spouse, loss of a job, an economic crisis, or severe illness in a close relative.

After correcting for potentially influential variables, their analysis revealed a positive association between exposure to more than one adverse life event and breast cancer. For these women, the risk of breast cancer was increased by 62 percent. "It wasn't enough to be exposed to one life event, a woman had to be exposed to more than one event," Peled said.

Compared with healthy women, women with breast cancer also demonstrated significantly higher scores of depression and significantly lower scores of happiness and optimism.

Moreover, the results showed a negative association between happiness and optimism and breast cancer. General feelings of happiness and optimism seemed to offer protection against breast cancer, Peled noted. "The more you are happy and feel optimistic with your life, the less the probability of developing breast cancer."

SOURCE: BioMed Central journal BMC Cancer, August 22, 2008.