From the Guidelines
Hot flashes during menopause are primarily caused by hormonal fluctuations, specifically declining estrogen levels, which affect the hypothalamus and trigger the body's cooling mechanisms, resulting in sudden intense heat, sweating, and chills. As estrogen decreases, it disrupts the hypothalamus's ability to regulate body temperature, leading to the sensation of hot flashes 1. Other factors that can worsen hot flashes include stress, caffeine, alcohol, spicy foods, tight clothing, smoking, and warm environments.
Factors that Exacerbate Hot Flashes
- Stress
- Caffeine
- Alcohol
- Spicy foods
- Tight clothing
- Smoking
- Warm environments
According to a study published in the Journal of the National Comprehensive Cancer Network, lifestyle modifications such as weight loss, quitting smoking, and limiting alcohol intake can help minimize vasomotor symptoms, including hot flashes 1. Additionally, cognitive-behavioral therapy (CBT) has been shown to reduce the perceived burden of hot flashes in breast cancer survivors 1.
Treatment Options
- Hormone replacement therapy (HRT)
- Nonhormonal pharmacologic options, such as selective serotonin reuptake inhibitors (SSRIs) and serotonin-norepinephrine reuptake inhibitors (SNRIs)
- Anticonvulsants, such as gabapentin
- Lifestyle modifications, such as weight loss, quitting smoking, and limiting alcohol intake
- CBT
It is essential to note that the most effective treatment for hot flashes is hormone replacement therapy (HRT), but its use is controversial due to associated health risks 1. Nonhormonal pharmacologic options, such as SSRIs and SNRIs, can also be effective in reducing hot flashes, but their use should be individualized based on risks and benefits 1.
Recommendations
- Lifestyle modifications, such as weight loss and quitting smoking, should be recommended as the first line of treatment for hot flashes.
- Nonhormonal pharmacologic options, such as SSRIs and SNRIs, can be considered for women who do not respond to lifestyle modifications or have contraindications to HRT.
- HRT should be used with caution and only in women who have a high risk of osteoporosis or other health benefits that outweigh the risks.
From the FDA Drug Label
Estrogens are hormones made by a woman's ovaries. The ovaries normally stop making estrogens when a woman is between 45 to 55 years old. This drop in body estrogen levels causes the "change of life" or menopause (the end of monthly menstrual periods) Sometimes, both ovaries are removed during an operation before natural menopause takes place. The sudden drop in estrogen levels causes "surgical menopause.” When the estrogen levels begin dropping, some women develop very uncomfortable symptoms, such as feelings of warmth in the face, neck, and chest, or sudden intense feelings of heat and sweating ("hot flashes" or "hot flushes").
The cause of hot flashes during menopause is the drop in body estrogen levels. This occurs when the ovaries stop producing estrogens, either due to natural menopause or surgical removal of the ovaries. As a result, some women may experience symptoms such as feelings of warmth and sudden intense feelings of heat and sweating, also known as hot flashes or hot flushes. 2
From the Research
Causes of Hot Flashes
- Hot flashes during menopause are caused by dysfunction of central thermoregulatory centers due to changes in estrogen levels 3
- Abnormal hypothalamic thermoregulatory control resulting in abnormal vasodilatory response to minor elevations of core body temperature also contributes to hot flashes 4
- Estrogen deficiency plays a cardinal role in the causation of hot flashes, along with other factors such as calcitonin gene-related peptide, hypothalamic kisspeptin, neurokinin B and dynorphin signal system, serotonin, and norepinephrine 4
- A narrowing of the thermoneutral zone (TNZ) triggered by estrogen fluctuations is also a accepted hypothesis for the cause of hot flashes 5
- Elevated central noradrenergic activation may also contribute to the narrowing of the thermoneutral zone, triggering hot flashes 6
- Small elevations in core body temperature acting within a reduced thermoneutral zone can trigger hot flashes 6, 7
Pathophysiology
- The mean increment in core body and skin temperature is 0.5°C and 0.25 - 3°C during a hot flush attack 5
- Hot flashes are triggered by small elevations in core body temperature, and procedures to reduce core body temperature can be beneficial 6, 7
- Estrogen ameliorates hot flashes by increasing the core body temperature sweating threshold, although the underlying mechanism is not known 6
- Elevated sympathetic activation acting through central alpha(2)-adrenergic receptors contributes to the initiation of hot flashes 7