Hot Flashes Health Article

Definition

Hot flashes, experienced by large numbers of women and some men as a result of surgical, chemical, or age-in duced changes in estrogen levels, are characterized by a rapid rise and discharge of heat with perspiration, discomfort, and possible redness. Ranging from mild to severe in intensity, they may be preceded by an "aura-like" experience, and may be followed by a subsequent feeling of chill. With natural age-related menopause, hot flashes may begin as early as two years prior to the cessation of menses and continue as long as five or more years afterward. Statistically, the average experience is approximately four years of hot flashes of varying intensities.

Description

Approximately 20% of women without breast cancer and 50–75% of women taking tamoxifen subsequent to breast cancer will reportedly seek a doctor's advice for the management of hot flashes. For women without breast cancer, this seems to be a conservative estimate, given that another source notes that as many as 75% of Caucasian women experience perimenopausally related hot flashes, beginning an average of two years prior to the cessation of menstruation. On average, 85% of these women experience hot flashes for more than one year. Statistics are mixed with regard to overall duration. One study reported that only 20% of women reported still having hot flashes after four years, while another reported 25–50% of women continuing to have them as long as five years. Hot flashes appear to be more common amongst African American women than among Caucasian, Japanese, Hispanic, or Chinese women, while Mayan Indian women report no symptoms associated with menopause at all.

Hot flashes may be preceded by a prodromal experience, or set of signs, of rapid heart rate, anxiety, and dizziness or weakness. There is considerable variation in the experience of hot flashes. As the flash comes on, there is a feeling of sudden heat that may produce as little as a beading of perspiration on the upper lip, or a sudden and uncontrollable drenching. The sudden feeling of heat may be followed by a cold, clammy sensation as evaporation of perspiration occurs. The episode may last from 30 seconds to five minutes; an average of four minutes is reported. One clinical source reported that patients most commonly describe the onset of hot flashes as coming between two and four in morning, disrupting sleep, often resulting in a need to change nightclothes or even bed linens; but another source noted that the most common time of onset was between six and eight in the morning and six and ten at night.

A stressful incident may precede the hot flash, and keeping a journal of these events as a means of identifying triggers may be helpful. Depending on the intensity, severity, and timing, embarrassment may also accompany the hot flash when others witness the sudden, unmistakable signs of the experience. Breast cancer, premature onset of menopause, faster onset of menopause, tamoxifen therapy in women and antiandrogenic therapies in women and men, may contribute to more severe and longer-lasting hot flashes. One source noted that each person individually may themselves experience a wide variation of symptoms, dependent on their unique biochemical, environmental, and psychosocial factors.

Causes & symptoms

The exact cause and mechanism of hot flashes is not well understood. What is recognized is that as estrogen levels are depleted, whether due to surgical, chemical, or natural age-related changes, the area in the brain that regulates several functions including body temperature—the hypothalamus—becomes "confused." The core body temperature set point is lowered, and the threshold between acceptable and nonacceptable body heat levels is more easily crossed. When that occurs, signals are sent to the rest of the body of a sudden need to discharge heat, accomplished through the sudden release of perspiration from the sweat glands. Studies reveal measurable rises in skin temperature. Other hypothalamic signals cause awakenings from sleep, changes in blood pressure and heart rate, and anxiety states (alertness), as if the body is in "fight or flight" mode.

A summary of common accompanying symptoms include:

• sleep disruptions
• fatigue
• night sweats
• heart palpitations
• irritability
• short-term memory loss
• attention span changes
• depression and weepiness
• uncharacteristic rage or impatience
• dryness of eyes and vagina
• reduced libido and interest in sex
• accelerated bone loss