Vol. 17• Issue 7 • Page 31
Harnessing the Hot Flash
More Choices for Midlife Women
by Ivy M. Alexander, NP
Approximately 5,700 women in the United States enter postmenopause each day, and many of them experience disruptive symptoms as a result of this transition (Table 1).1,2Hot flashes and vasomotor symptoms (night sweats, flushing, heat intolerance) are the most common symptoms experienced by postmenopausal women, and they affect women in most ethnic and racial groups.1,3
Today's midlife women tend to view menopause as a normal part of life - not a medical problem that must be treated.4-7Hand in hand with this shift, women are scrutinizing their choices for symptom management: lifestyle changes, complementary and alternative medicine (CAM), nonhormonal prescriptions and low-dose hormone therapy (HT).
CAM for Symptom Management
The use of CAM in the United States is at its highest level in history, and women are dominant drivers of this trend.8Approximately half of postmenopausal women seek nonhormonal options to manage their menopause-related symptoms.9-12CAM refers to medications or therapies used in conjunction with (complementary) or instead of (alternative) traditional medicine and include diet, energy medicine, mind-body therapies, body manipulation, botanical remedies, and relaxation techniques.13,14Several CAM therapies have been evaluated for hot flash management: lifestyle changes, botanical remedies, paced deep breathing and acupuncture.
Lifestyle changes can reduce the frequency and severity of hot flashes.1,5For example, avoiding dietary triggers such as caffeine (all forms), alcohol and concentrated sugar can reduce the frequency of vasomotor symptoms. Drinking water with ice can help reduce core temperature when a hot flash occurs. Although it is not specifically proven to reduce hot flashes, increased water consumption can be helpful because it replaces fluids lost in sweating. Smoking cessation can also reduce hot flashes.15
Other environmental changes can be useful.1,4,5Wearing clothing made of cotton, washable linen or fabrics that wick sweat away from the skin and increase air movement can increase comfort. Synthetic materials such as polyester can trap body heat and trigger hot flashes. Synthetic fabrics can also make hot flashes more uncomfortable. Similarly, wearing layers that can be easily removed and avoiding turtlenecks, shirts with a high neckline, tight clothing and extra layers (e.g., slips, girdles) can reduce discomfort. Breathable fabric choices are also important in bedding and sleepwear. Another strategy is to keep ambient room temperature at a constant, moderately cool level by setting the thermostat conservatively and using a fan to circulate air.
Daily aerobic exercise helps reduce hot flash frequency and severity by assisting in body temperature regulation.16-19Exercise also reduces cardiovascular disease and osteoporosis risk and assists in maintaining normal blood glucose levels and weight. Regular exercise is associated with a higher quality of life among midlife women and can help improve depression, soreness or stiffness, palpitations, memory, and sleep quality.16-20Midlife women should be evaluated for underlying cardiovascular disease prior to starting a new exercise regimen. Although 1 hour of daily exercise is the goal, even small amounts of exercise can help reduce hot flashes.16,18
The herbs most often used for hot flash management are black cohosh, dong quai, ginseng and oil of evening primrose.21,22Isoflavones (red clover, soy) are a type of phytoestrogens. Phytoestrogens are plant-derived compounds that have some estrogen-like actions in the body. Isoflavones are the most widely used phytoestrogens for vasomotor symptom management.1Evidence supporting the use of herbal and isoflavone products for menopause symptom relief is contradictory (Table 2). Among this group, black cohosh has demonstrated the most efficacy.
The black cohosh plant is indigenous to North America. Dried root and rhizome are used medicinally for hot flashes in oral daily doses of 40 mg to 200 mg (or as an ethanolic extract in a dose equal to 40 mg of dried root and rhizome). Side effects are usually mild and transient. The evidence of estrogenic activity with black cohosh is controversial, so endometrial activity should be monitored in all women who use this product.23,24Due to case reports of hepatitis and liver toxicity, warn patients to report any symptoms that suggest liver problems (e.g., jaundice, abdominal pain, vomiting, anorexia).25Whether black cohosh itself has caused these problems or the additives, contaminants or extraneous material in the preparations are responsible remains unclear.
Advise women to choose dietary supplements produced by a reputable company. Inform them that variations in production can change the ingredients from dose to dose and that different forms of products (e.g., tincture versus tablet or powder) are not equivalent. ConsumerLabs (www.consumerlab.com) is an independent company that tests and provides objective reviews of many over-the-counter supplements. For patients who want to use soy, herbs or other dietary supplements, the $24.95 annual subscription fee to access ConsumerLabs data is a wise expenditure.
Deep Breathing and Relaxation
Slow, deep breathing, referred to as paced respirations, can reduce hot flashes.26-28When the hot flash begins, the woman breathes in deeply for a count of four, holds her breath for a count of seven, then slowly exhales over a count of nine. This breathing is used in some forms of yoga.
Relaxation may be an important factor in the effectiveness of deep breathing because stress has been identified as a trigger for hot flashes.4Avoiding stress, using effective stress management techniques and practicing yoga have all been linked to reduced hot flashes.4,29
Acupuncture is known to provide relaxation and pain relief. Several studies have also evaluated its efficacy for hot flash reduction. Of eight studies published between 1995 and 2008, three documented a significant decrease in hot flash severity, and one demonstrated a significant reduction in hot flash frequency for both treatment and so-called sham acupuncture as compared with no acupuncture.30-37None of the other studies demonstrated a significant reduction in hot flash frequency. The methods used in the studies differed in terms of treatment length and comparisons against no acupuncture, sham acupuncture, electroacupuncture and general tonic acupuncture, making it difficult to reach general conclusions about its efficacy for hot flash relief. Three of the studies demonstrated beneficial effects on mood, and one showed no difference.30,31,33,37
Similarly, in a meta-analysis review of published acupuncture research, the authors concluded that convincing evidence for the use of acupuncture for hot flashes was lacking.38Nevertheless, acupuncture is a well-accepted complementary therapy. Placebo effects and relaxation achieved with this modality may reduce hot flashes enough to be beneficial for some women.
Nonhormonal Prescription Products
In addition to CAM and lifestyle options for menopause-related hot flash management, nonhormonal prescription medications are available. Four of six trials evaluated in a 2006 meta-analysis determined that some selective serotonin reuptake inhibitors (SSRIs, specifically paroxetine, fluoxetine and citalopram) and serotonin norepinephrine reuptake inhibitors (SNRIs, specifically venlafaxine) were effective in managing hot flashes.39Other trials have expanded the data supporting the efficacy of older SSRIs such as sertraline (Zoloft) and have documented the fficacy of newer SNRIs such as desvenlafaxine (Pristiq) and other formulations of existing SSRIs, such as controlled release paroxetine (Paxil).40-43
Other nonhormonal prescription medications are effective in reducing vasomotor symptoms. The same 2006 meta-analysis determined clonidine (Catapres) to be effective for reducing hot flash frequency in four of the 10 studies evaluated.39These researchers also found significant vasomotor symptom reduction among women who used gabapentin (Neurontin) in two of two studies and in women who used methyldopa (Aldomet) in three of three studies. Moclobemide (Aurorix) and veralipride (Agreal) were identified as somewhat effective.39
Nonhormonal prescription medications can provide vasomotor symptom management options for women who are unable or unwilling to take HT. The choice of agent must be individualized to avoid unwanted effects. Side effects can sometimes increase menopause-related symptoms, such as sexual dysfunction with SSRI or SNRI use or heightened daytime fatigue with gabapentin. Other medications may cause side effects that are intolerable, such as hypotension or arrhythmia with clonidine. Despite its efficacy, methyldopa is not recommended for hot flash management because of its known risk for toxicity.1
Conversely, if a woman desires medication therapy for hot flashes and also has another condition that warrants treatment with a agent known to reduce hot flashes, a single agent may manage both concerns. For example, if a woman is experiencing depression, use of one of the SSRIs or SNRIs may effectively manage both her depression and her hot flashes. Likewise, if a woman with hot flashes also has chronic headaches or pain, she might find effective relief for both problems in gabapentin.
Careful consideration of the off-label use of these medications for hot flashes is warranted. Many of the studies that evaluated nonhormonal prescription medications for vasomotor symptoms were performed on breast cancer survivors, thus the effectiveness of these medications in women who have not had breast cancer is not as clear.
HT remains the most effective option for menopause-related vasomotor symptom management.39,44Based on several comprehensive research trials, most national women's health organizations along with the U.S. Preventive Services Task Force and the Food and Drug Administration have reached similar conclusions about HT: Estrogen-progesterone therapy (EPT) and estrogen therapy (ET) can be used to manage moderate to severe postmenopausal vasomotor symptoms at the lowest possible dose, and therapy should be continued for the shortest period of time possible.44-54According to reanalysis of Women's Health Initiative (WHI) results for the EPT and ET arms by age cohorts, initiating therapy arly in the immediate postmenopause period is not associated with an increased risk for heart disease.55,56
Furthermore, a recent reanalysis of data from the EPT arm that evaluated breast cancer incidence showed that for the first 2 years of therapy, women who received EPT actually had a lower incidence of newly diagnosed breast cancer than women treated with placebo.57The overall incidence of breast cancer did increase among women in the treatment group over the course of the full trial (5.6 ears). This increased risk declined quickly for both groups after the study period concluded, and it was independent of mammography frequency rates. In its 2008 position statement on HT, the North American Menopause Society (NAMS) noted an increase in breast cancer risk when HT is used for 3 to 5 years or more.44
Surveys indicate that between 15% and 40% of women use HT.58,59This rate reflects a decline over the past several years, especially since the initial WHI results were published.44However, as the reassessment of the WHI data shows, HT can provide a safe and effective option for women with moderate o severe vasomotor symptoms during the first few years following menopause.47-49,55,56Postmenopausal women with existing heart disease, those who are breast cancer survivors or those who have unexplained vaginal bleeding are not good candidates for HT. To protect against endometrial overgrowth and cancer, women who have an intact uterus must receive progesterone in addition to estrogen.44
Just as with nonhormonal prescription medications, careful selection of an HT combination is necessary. Treatment should be tailored to meet each woman's needs and should take into consideration her full symptom profile, medical history, health risks and personal preferences. Women who are at risk for bone loss or who experience symptoms such as sleep interruptions, skin changes or vaginal dryness benefit from the bone protective and positive effects of HT on these symptoms in addition to hot flash management.
Among women who do select HT for hot flash management, newer low-dose options and unique methods for delivery are often considered. NAMS recommends starting therapy at a low dose and increasing it only if needed for symptom control.44Small increments in dose can be tried after 6 weeks because it often takes this long to achieve symptom benefit from a pecific dose. Low oral doses of conjugated equine estrogen (CEE) (0.3 mg) with or without medroxyprogesterone acetate (1.5 mg) can reduce the frequency and severity of hot flashes.60Similarly, transdermal estrogen patch doses as low as 0.014 mg/day (such as that found in Menostar) can effectively control hot flashes.61
Multiple ET and EPT doses and formulations are now available in oral form. If effective symptom management is not achieved with the initially selected estrogen or estrogen-progestogen formulation, change to a different estrogen or progestogen formulation.
Some women prefer to use bioidentical hormones.62These are considered equal in efficacy and risk to traditional estrogen and progesterone formulations.62Compounded bioidentical hormones carry the same risks as traditional HT formulations. No data support the practice of hormone or saliva testing for titrating compounded doses.1,62,63
For each fully informed woman who chooses HT, tailor the prescription to her comfort level. If her preference is to use an oral bioidentical formulation, FDA-approved formulations such as 17-beta estradiol in Estrace or Femtrace and micronized progesterone in Prometrium are available.
Some women prefer transdermal preparations. Because transdermal estrogen and progestogen largely bypass the liver first-pass effect, they are dosed at a lower level than oral HT. Transdermal HT is also less likely to interfere with other medications that require liver metabolism. For these reasons, transdermal therapy is sometimes the preferred route for women with chronic conditions such as hypertension or high cholesterol. Transdermal estrogen is less likely than oral estrogen to increase HDL cholesterol or cause problems for women with a history of gallbladder disease.
In addition to estrogen patches (e.g., Alora, Climara, Vivelle, Estraderm, Esclim) or estrogen-progestogen patches (e.g., Climara Pro, Combipatch), new transdermal estrogen formulations are now available. These include gels (e.g., Estrogel, Divigel, Elestrin), a spray (Evamist) and a cream (Estrasorb). Dosing for these products ranges from daily to weekly. The range of options now available increases the likelihood of finding a delivery system that manages symptoms and meshes with a woman's preferences and lifestyle.64,65
Putting It Into Practice
A stepped approach is recommended for treating vasomotor symptoms in postmenopausal women. Start with lifestyle changes and CAM, then consider adding prescription nonhormonal medication or HT if needed.66Lifestyle changes and some CAM modalities (e.g., relaxation, acupuncture) can be continued if a woman needs prescription therapy; they may reduce the dose required to control her symptoms.
Many women seek alternative and more natural methods for managing hot flashes. Similarly, many providers are interested in nonhormonal options. Although current research does not strongly support the efficacy of CAM modalities for vasomotor symptom relief, many of these therapies are safe. If they provide relief, the benefit is significant. As more research is done to evaluate CAM, other useful modalities may be identified.
HT remains the single most effective option for hot flash management.44,64,65Because most women experience a peak in hot flashes in the first few years after menopause and a decline in intensity and frequency after about 5 to 7 years, and because HT is a safe and effective therapy in the first few years after menopause, it remains a viable option for many women.67
The array of treatment options for vasomotor symptoms is greater than ever. Nurse practitioners can partner with women to tailor safe, effective treatment plans that meet each patient's individual needs and preferences for vasomotor symptom management.
Ivy Alexander is an adult nurse practitioner with a PhD who specializes in women's health. She is an associate professor at Yale University School of Nursing in New Haven, Conn., and she is a midlife women's health consultant at Yale University Health Services, also in New Haven.
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