Vasomotor Symptoms or Hot Flushes?
Vasomotor symptoms (VMS) affect 80% of women undergoing menopause, which usually occurs in the late forties or early fifties. Vasomotor symptoms are also called hot flashes or flushes, and night sweats and are due to dilation of blood vessels that cause heat to rise to the surface of the skin.
Menopause is defined as the absence of menses for one year due to low levels of estrogen, progesterone, and elevated levels of follicle stimulating hormone (FSH). FSH is secreted from the pituitary gland in the brain in response to lower production of estrogen from the ovaries.
Ovaries, like any organ, are subject to a decline in function as they age. Ovaries’ main functions are ovulation, estrogen and progesterone production, and maintenance of early pregnancy. As these hormones decrease, the pituitary tries to trigger the ovaries to work harder by releasing higher and higher levels of FSH. However, the aged ovaries are exhausted and do not respond.
What are Vasomotor Symptoms?
VMS can occur for months or years prior to the cessation of menses. Most VMS are moderate or severe and can have significant harmful effects on quality of life. At their core, VMS are thermoregulatory heat dispersion events that appears to have a narrower trigger zone in the menopausal years, meaning that small fluctuations in core body temperatures can trigger heat loss events such as sweating from peripheral vasodilation (hot flash).[1]
As such, vasomotor stands for ‘vaso’ or blood vessels and ‘motor’ means movement and is associated with dilation of the smooth muscle in the walls of the blood vessels. When blood vessels dilate, they release heat into the surrounding tissue and are responsible for people feeling hot and sweating. Thus, VMS include hot flashes or flushes, night sweats, and flushed skin.
Why do VSM Symptoms Occur?
The presumed reason for VMS is thought to be estrogen deficiency because supplementation of estrogen appears to stop or prevent hot flashes. However, other systems are implicated in the process such as central (brain) serotonergic, noradrenergic, opioid, adrenal, and autonomic systems, as well as vascular processes.[2-6]
How Long do VSM last?
The length and severity of menopausal symptoms are highly individualized and depend on a variety of factors such as whether your menopause occurred naturally or surgically, your ethnicity, your mother’s history, obesity, smoking, and alcohol intake. For instance, surgical removal of the ovaries, often done at the time of a hysterectomy, can result in the abrupt onset of hot flashes that are severe and debilitating.
This contrasts with natural menopause whereby the ovaries still produce a tiny amount of estrogen. Other co-morbidities like thyroid disorder and diabetes may influence the duration of symptoms. Most women experience the most severe symptoms in the early years and then they taper off rather gradually. However, certain triggers such as ambient temperature, certain foods, and anxiety may exacerbate or prolong the duration of symptoms.
In a study by Avis and colleagues [7], they used data from the Study of Women’s Health Across the Nation (SWAN) and showed that Black women experienced the longest total VMS duration (median, 10.1 years). Japanese and Chinese women reported the shortest VMS duration (median, 4.8 years and 5.4 years, respectively). For non-Hispanic women, the median total VMS durations were 6.5 years and 8.9 years for Hispanic women.
Risk Factors of Vasomotor Symptoms
VMS are associated with a higher risk for cardiovascular disease and greater bone density loss. Other risk factors for the severity of VMS are obesity, smoking, low levels of exercise, and alcohol intake as well as psychologic parameters such as: [8-12]
- attitudes toward menopause
- symptom sensitivity
- anxiety, irritability, or grouchiness,
- tenseness or nervousness,
- pounding or racing heart,
- fearfulness for no reason
- perceived stress
- depressive symptoms
- level emotional and social support
The best way to reduce your risk factors is to exercise regularly, lose weight, stop smoking, and reduce or stop alcohol intake.
It is also important to make sure the temperature in the room is comfortable and there is good air movement. It is best to add layers to your clothing rather than wear one heavy garment. That way, you can add a sweater to a blouse, but not have to change clothes all together. Wear lightweight, moisture-wicking fabrics and avoid spicy foods. Keep well-hydrated and if your symptoms are severe, see your healthcare practitioner for advice and management.
References
- Freedman RR, Krell W. Reduced thermoregulatory null zone in postmenopausal women with hot flashes. Am J Obstet Gynecol. 1999;181(1):66–70.
- Thurston R, Christie I, Matthews K. Hot flashes and cardiac vagal control: A link to cardiovascular risk? Menopause. 2010;17(3):456–461.
- Woods NF, Mitchell ES, Smith-Dijulio K. Cortisol levels during the menopausal transition and early postmenopause: observations from the Seattle Midlife Women’s Health Study. Menopause. 2009;16(4):708–718.
- Freedman RR, Woodward S. Elevated a2-adrenergic responsiveness in menopausal hot flushes: pharmacologic and biochemical studies. In: Lomax P, Schonbaum E, editors. Thermoregulation: the pathophysiological basis of clinical disorders. Krager; Basel: 1992. pp. 6–9.
- Casper RF, Yen SS. Neuroendocrinology of menopausal flushes: an hypothesis of flush mechanism. Clin Endocrinol (Oxf) 1985;22(3):293–312.
- Sturdee DW. The menopausal hot flush–anything new? Maturitas. 2008;60(1):42–49.
- Avis NE, Crawford SL, Greendale G, Bromberger JT, Everson-Rose SA, Gold EB, Hess R, Joffe H, Kravitz HM, Tepper PG, Thurston RC; Study of Women’s Health Across the Nation. Duration of menopausal vasomotor symptoms over the menopause transition. JAMA Intern Med. 2015 Apr;175(4):531-9. doi: 10.1001/jamainternmed.2014.8063. PMID: 25686030; PMCID: PMC4433164.
- Sommer B, Avis N, Meyer P, et al. Attitudes toward menopause and aging across ethnic/racial groups. Psychosom Med. 1999;61(6):868-875.
- Barsky AJ, Goodson JD, Lane RS, Cleary PD. The amplification of somatic symptoms. Psychosom Med. 1988;50(5):510-519.
- Cohen S, Kamarck T, Mermelstein R. A global measure of perceived stress. J Health Soc Behav. 1983;24(4):385-396.
- Radloff LS. The CES-D Scale: a self-report depression scale for research in the general population. Appl Psychol Meas. 1997;1:385-401.
- Sherbourne CD, Stewart AL. The MOS social support survey. Soc Sci Med. 1991;32(6):705-714.