High Stress Appears to Lower Immune Function in Breast Cancer

SEATTLE--Breast cancer patients who report high levels of personal stressscore lower on three measures of immune function than less stressed womenwith the disease, said Barbara L. Andersen, PhD, professor of psychologyand obstetrics and gynecology, Ohio State University, Columbus.

In her presentation at the annual meeting of the American Associationfor the Advancement of Science (AAAS), Dr. Andersen reported preliminaryfindings from an ongoing study she is conducting with Ronald Glaser, PhD,and William Farrar, MD.

Women enrolled in the trial are tested for the ability of their naturalkiller (NK) cells to find and destroy target cells; the reaction of NKcells to gamma interferon, which normally stimulates these cells; and howwell their blood cells replicate in the presence of two plant chemicals,ConA and PHA.

"The results were surprisingly strong and clearly suggested anassociation between high stress and lower levels of immunity in breastcancer patients," Dr. Andersen said.

Low-stress women showed greater NK cell activity than did women assessedas high stress. However, she pointed out, "high levels of stress didnot reduce the number of NK cells; rather, stress seemed to make the NKcells less effective."

The immune system findings held up when the Ohio State University teamcontrolled for factors known to influence the immune systems of breastcancer patients, including age, disease severity, and days since cancersurgery.

The findings are consistent with work by Dr. Glaser and others at OhioState's Institute for Behavioral Medicine Research that has linked stresswith reduced immune system functioning in relatively healthy people.

"We're showing that the same relationship between stress and immunefunction occurs in people with cancer," Dr. Andersen said.

The preliminary report included immune function data from 115 womenwith stage II or III breast cancer. The women were treated at Ohio State'sJames Cancer Hospital and Research Institute or by collaborating physiciansin the Columbus, Ohio, region. The researchers expect to enroll a totalof 230 breast cancer patients and follow them for up to five years.

Women enter the study between their surgery and their adjuvant therapy.They answer questionnaires designed to reveal evidence of stress, suchas intrusive thoughts about their breast cancer or attempts to avoid thinkingor talking about the cancer.

The women are randomized to two groups: one groups is assessed onlyfor stress and serves as the control; the second is assessed and receivespsychological intervention.

The Intervention Program

In this intervention program, the women meet in structured group sessionsthat target reducing stress, increasing positive and decreasing negativehealth behaviors, improving treatment compliance, and enhancing qualityof life (by improving coping skills, mobilizing a social support network,and dealing with breast-specific problems such as sexual functioning).

Preliminary findings suggest that the women receiving intervention havesignificantly better adjustment and enhanced quality of life than thosein the assessment-only group, and show much higher patient compliance.

What remains unanswered is whether reducing stress can actually prolongthe life of patients. Thus, the Ohio State University team is also assessingoutcomes in these patients, although no data are yet available.

"Psychological interventions may play an important role, not justin improving quality of life but also in improving the health of breastcancer patients," Dr. Andersen said. "That's what we're exploringnow."