Stress ‘doubles chances’ of contracting breast cancer

STRESS may double a woman’s chances of developing breast cancer, new research has shown.

The link emerged from a Swedish study of 1,350 women who were monitored for 24 years.

Although experts warned more work was needed to confirm the results, the findings were said to be significant. They suggest that suffering stress can dramatically increase the chances of having breast cancer many years later.

At the start of the investigation in 1968 the women were given a physical examination and questioned about stress. They were asked if they had experienced feelings and symptoms of stress, such as tension, fear, anxiety and sleep disturbances, for a month or longer.

Six degrees of stress were recorded, ranging from none, to suffering constantly over the previous five years. The women had follow-up examinations in 1974/’75, 1980/’81, and 1992/’93, but were not questioned about stress again.

Researchers from the Sahlgrenska Academy in Gothenburg found that stressed women were twice as likely to develop breast cancer over the 24-year follow-up period as those who said they experienced no stress.

Dr Osten Helgesson, who presented the findings at the ECCO12 European Cancer Conference in Copenhagen yesterday, said: “This study is prospective and is based on information that is unbiased with respect to knowledge of disease.

"Therefore, it can be regarded as more valid than results drawn from case-control studies.

“It showed a statistically significant, positive relationship between stress and breast cancer, and this association was independent of potential confounding factors, such as alcohol, body mass index, education, maternal history of breast cancer, smoking, age at which the women started their periods, age at which they had their first baby, the interval between the two, and their age at menopause.”

Of 1,350 women, 24 who had experienced stress went on to develop breast cancer. A further 432 who had experienced stress did not develop the disease.