Many women enduring hot flashes experience the heat, sweat and reddened upper body as an uncomfortable inconvenience. However, hot flashes can greatly diminish a woman's quality of life, disrupting sleep at night or causing embarrassment as she goes about her daily business.
Hot flashes, called flushes in medical circles, occur commonly in women with a history of breast cancer. The problem arises naturally in these women because of menopause; because of various treatments, such as the drugs tamoxifen and aromatase; and because of chemotherapy.
A new Cochrane review finds that a variety of non-hormonal treatments (mostly non-hormonal drugs) can offer women who have had breast cancer some relief from hot flashes. Side effects are frequent, however, and must weigh into any decisions to use the interventions.
Researchers in Chile analyzed 16 studies including 1,461 women and found that several different non-hormonal drugs and one non-drug treatment, relaxation therapy, might help relieve symptoms.
The review was published by The Cochrane Collaboration, an international organization that evaluates medical research. Systematic reviews draw evidence-based conclusions about medical practice after considering both the content and quality of existing medical trials on a topic.
Non-hormonal therapies included medications and complementary type interventions that do not appear to alter a woman's hormonal state. For this reason, several "holistic" remedies such as black cohosh and phytoestrogens do not qualify as non-hormonal because they might alter a woman's hormonal balance.
"Several non-hormonal alternatives have been proposed for managing hot flushes in these patients, but none is clearly superior. Our review was intended to review the existing evidence on several pharmacological and non-pharmacological treatments that can help," said lead author Gabriel Rada, M.D. He serves as the director of the Evidence-Based Medicine Unit at the Catholic University of Chile.
"We found that relaxation therapy, the antihypertensive clonidine, the anticonvulsant gabapentin, and some antidepressants that inhibit serotonin reuptake, have a mild to moderate effect," Rada said. "Our review is not able to say which alternative is superior, and some of them have adverse effects, so the choice must be made on an individual patient basis."
The pharmacological agents included were vitamin E, clonidine (used widely to treat high blood pressure), gabapentin (a seizure medicine) and various antidepressants in the categories of SSRIs and SNRIs.
Non-drug interventions were magnetic therapies (devices placed on patients' skin), relaxation therapies (various stress management techniques), acupuncture and homeopathy.
Because of inconsistencies in the ways that the 16 studies presented the data, the Cochrane researchers could not compare the relative strength of the beneficial effects of the different treatments.
Susan M. Cohen, Ph.D., an associate professor at the University of Pittsburgh School of Nursing studies acupuncture as an intervention for hot flushes.
"Because of the small number of studies used, they really can't make a recommendation that says that a certain intervention will help a large percentage of women," she said. "This isn't a statement about the value of the studies that were included, but a statement about the criteria they set. They created a very small set of studies to consider."
Cohen added that this Cochrane review only included studies consisting of at least 80 percent women with a breast cancer history. It thus excluded many studies that looked at non-hormonal interventions in groups that included a higher proportion of women without the disease, but still had sizable breast cancer populations, even if studies examined the two groups separately.
"The beneficial effects they found with the medications, with regard to the number, frequency or severity of the flushes, were statistically significant, but it's not clear that those effects were clinically significant," Cohen said. "And you have to ask if the side effects were worth those benefits."
For example, she said, anti-seizure medication might force a woman to give up driving. She pointed out that clonidine lowers blood pressure even in women who do not have high blood pressure and its possible side effects include dizziness, dry mouth, constipation and a skin reaction.
"Women who are breast cancer survivors are often reluctant to take another medication because they are concerned about long-term effects," Cohen added.
She strongly agreed with the review authors that there is a need for more research into effective, safe, hot flash treatments in women with breast cancer.