Breast cancer is one of the most frequent cancers worldwide and its treatment can produce disturbing symptoms including hot flushes, the sudden feeling of heat in the face, neck and chest. Hormonal treatments are used to control such symptoms in postmenopausal women but for women with a history of breast cancer these are not recommended as they can induce cancer growth. The aim of this review is to evaluate the efficacy of non-hormonal interventions in treating hot flushes in such women.
We found 10 randomised controlled studies assessing pharmacological therapies and six assessing non-pharmacological treatments (complementary or alternative therapies). The 10 studies on pharmacological therapies included two on clonidine (an antihypertensive that stimulates a norepinephrine receptor implicated in the initiation of flushes), one on gabapentin (an anticonvulsant that diminishes hot flushes through an unknown mechanism), six on selective serotonin or serotonin-norepinephrine reuptake inhibitors (antidepressants that increase the levels of serotonin and norepinephrine, both implicated in the generation of hot flushes) particularly venlafaxine, paroxetine, sertraline and fluoxetine, and one on vitamin E (mechanism unknown).
Clonidine, antidepressants and gabapentin reduced the number and severity of hot flushes. Vitamin E did not reduce the number or severity of hot flushes.
Of the six studies evaluating non-pharmacological therapies, two were on homeopathy (one evaluated a single homeopathic remedy in a group and the Hyland's menopause formula in a second group; and the other study evaluated homeopathic medicines in tablet, granule or liquid form, prepared by a single pharmacy), two on relaxation therapy (occupational therapist-guided relaxation consisting in stress management, written information about stress, deep breathing techniques, muscle relaxation and guided imagery), one on acupuncture (eight treatment sessions, 19 acupuncture points) and one on magnetic therapy (magnetic devices attached to participants' skin, placed over acupuncture or acupressure sites).
In the studies on non-pharmacological therapies, relaxation therapy was the only one that probably reduced the frequency and severity of hot flushes. Homeopathy, acupuncture and magnetic therapy may not lead to any differences in the number and severity of hot flushes.
One limitation of our review is that it is not possible to say if some treatments are better than others. Another limitation is that adverse effects were not clearly reported in all studies.
Clonidine, SSRIs and SNRIs, gabapentin and relaxation therapy showed a mild to moderate effect on reducing hot flushes in women with a history of breast cancer.
Hot flushes are common in women with a history of breast cancer. Hormonal therapies are known to reduce these symptoms but are not recommended in women with a history of breast cancer due to their potential adverse effects. The efficacy of non-hormonal therapies is still uncertain.
To assess the efficacy of non-hormonal therapies in reducing hot flushes in women with a history of breast cancer.
We searched the Cochrane Breast Cancer Group Specialised Register, CENTRAL (The Cochrane Library), MEDLINE, EMBASE, LILACS, CINAHL, PsycINFO (August 2008) and WHO ICTRP Search Portal. We handsearched reference lists of reviews and included articles, reviewed conference proceedings and contacted experts.
Randomized controlled trials (RCTs) comparing non-hormonal therapies with placebo or no therapy for reducing hot flushes in women with a history of breast cancer.
Two authors independently selected potentially relevant studies, decided upon their inclusion and extracted data on participant characteristics, interventions, outcomes and the risk of bias of included studies.
Sixteen RCTs met our inclusion criteria. We included six studies on selective serotonin (SSRI) and serotonin-norepinephrine (SNRI) reuptake inhibitors, two on clonidine, one on gabapentin, two each on relaxation therapy and homeopathy, and one each on vitamin E, magnetic devices and acupuncture. The risk of bias of most studies was rated as low or moderate. Data on continuous outcomes were presented inconsistently among studies, which precluded the possibility of pooling the results. Three pharmacological treatments (SSRIs and SNRIs, clonidine and gabapentin) reduced the number and severity of hot flushes. One study assessing vitamin E did not show any beneficial effect. One of two studies on relaxation therapy showed a significant benefit. None of the other non-pharmacological therapies had a significant benefit. Side-effects were inconsistently reported.