Feeling stressed could play a role in the development of cervical cancer, a new report suggests.
But experts say the findings are still preliminary and it's too soon to rush out and enroll in a stress-management course in hopes of combating the disease.
The human papillomavirus (HPV) has long been known as the primary cause of cervical cancer, but the virus alone doesn't seem to be enough to induce the disease. Most sexually active women will contract HPV at some point in their lives, but 90 percent will clear the virus from their body before it causes any damage, suggesting other factors are at play in the unfortunate minority who eventually develop cervical cancer.
The new study, published Friday in the journal Annals of Behavioral Medicine, found that feeling stressed out may be one such factor by impairing the body's ability to fight off the virus.
“Women who reported higher levels of perceived stress — regardless of what was actually happening in their life — showed an impaired immune response to HPV,” said Carolyn Fang, a psychologist at Fox Chase Cancer Center in Philadelphia and lead author of the study.
Too early for alarm
However, it's too early to sound the alarm, Fang added. More research is needed to confirm the finding and show that reducing stress improves the body's ability to fight off HPV.
“I don't want women to think that just because they're feeling stressed they will get cervical cancer,” Fang said.
Previous research has indicated that women with higher levels of stress were more likely to develop cervical cancer, so Fang's team decided to look at whether stress somehow impaired the body's immune response to HPV.
The study involved 74 women who had abnormal Pap smears that revealed precancerous cells and another 28 women who had normal Pap results. (Half of the women with abnormal Pap results were infected with HPV strains known to cause cancer, including the culprit known as HPV-16, compared with about 18 percent of the women with normal Pap tests.)
The women with abnormal Paps underwent blood tests and also were asked about their perceived stress over the last month and about actual major stress events in the past six months, such as death of a family member, divorce or being fired from work.
Results showed that the women with precancerous cells who reported a higher level of perceived stress also showed a poorer immune response to HPV-16.
Perceived stress to blame Notably, only perceived stress and not actual stressful life events were associated with this weakened immune response. One possible explanation for this discrepancy is that the women were asked about perceived levels of stress over the past month whereas actual stressful events were over the past six months, so it could be that the more recent perceived stress has a bigger impact on immune function than actual events that may have occurred further in the past, the researchers said. Another explanation is that perceived stress levels may be more important than actual stressful events because people respond to and handle stressful situations differently.
The women with normal Pap results did not complete the stress questionnaire, so it's not known whether stress had any impact on their immune response to HPV.
Dr. Maureen Killackey, a gynecological oncologist at Memorial Sloan-Kettering Cancer Center in New York and chair of the New York State Breast and Cervical Cancer Advisory Council, said that while the findings are interesting, they're not enough to pin the blame for cervical cancer on stress.
But she noted that many researchers speculate that stress may somehow be involved in cervical cancer because stressful times in women's lives can often be associated with abnormal Pap smear results.
Fang's team is currently conducting another study that may shed more light on this issue. The study is looking at whether a program that involves meditation and other stress reduction techniques improves women's immune response to HPV or cervical cancer.
Robert Smith, director of cancer screening at the American Cancer Society, said if further research confirms the connection, then this could be another reason for women to receive the HPV vaccine, Gardasil, which is currently recommended for those between the ages of 9 to 26.
“It means the vaccine would be doing the work and you wouldn't be relying on trying to avoid stress as a co-factor to prevent the cancer,” Smith said.
None of the participants in the study had received Gardasil because the vaccine, which was only approved by the Food and Drug Administration in 2006, was not yet available at the time of the research.
Steve Mitchell is a science and medicine writer in Washington, D.C. His articles have appeared in a variety of newspapers, magazines and Web sites, including UPI, Reuters Health, The Scientist and WebMD.