Vasomotor Symptoms

The vasomotor system includes the nerves and the structures from which they arise (e.g., the medulla oblongata or spinal cord) that regulate blood flow to specific organs or body parts by controlling the blood vessels’ internal diameter. 

Vasomotor symptoms (VMS) are synonymous with menopause,  including hot flushes and night sweats. They affect the majority of individuals to some extent during the climacteric period. Vasomotor symptoms can be defined as periodic episodes of intense heat accompanied by sweating or flushing.

They usually affect the head, neck, chest, and upper back, lasting 3–10 minutes, and may occur multiple times each day. In some cases, vasomotor symptoms may be accompanied by feelings of anxiety and palpitations.

The severity of vasomotor symptoms usually peaks between late perimenopause and early post-menopause. However, they may occur much earlier, even before the onset of menstrual irregularities, and persist into a person’s 60s or 70s. For this reason, it is essential that practitioners learn how to treat hot flushes and night sweats to alleviate their patients' suffering.

Pathophysiology

As women approach menopause, their ‘thermoregulatory zone’ narrows, meaning the range within which normal body temperature is maintained reduces. Thus, even small fluctuations in the external temperature can trigger a homeostatic response, including peripheral vasodilation and perspiration.

The exact physiological mechanism underlying vasomotor symptoms is unclear. However, they appear to be the result of multiple central and peripheral systems interacting abnormally due to fluctuating oestrogen and FSH levels. The fact that oestrogen replacement therapy reduces vasomotor symptoms suggests that reduced oestrogen levels are a critical factor.

The serotonergic, noradrenergic, autonomic, and vascular systems may all play a role in the development of vasomotor symptoms. There is also some inconsistent evidence suggesting the involvement of the endogenous opioid system. One theory suggests that decreased oestrogen levels increase noradrenaline release, upregulating hypothalamic serotonin receptors, which play a role in temperature control.

Risk Factors

Although vasomotor symptoms are extremely common, the following risk factors can predict more severe, more frequent, and longer-lasting problems:

Ethnicity

According to the large-scale Study of Women's Health Across the Nation (SWAN) study, the ethnic group most likely to be severely affected by vasomotor symptoms is African-Americans. The least likely groups to suffer are Chinese and Japanese women, while Caucasian and Hispanic women report similar rates of vasomotor symptoms.

The reason for these differences is unclear. In the past, it has been suggested that East Asian women suffer fewer vasomotor symptoms due to a higher soy intake. However, this does not appear to be the case. Other possible explanations are cultural differences in the way menopause is interpreted, experienced, and reported to health professionals, particularly in cultures where doctors are mostly male.

Obesity

Women with a higher body mass index, especially those carrying excess abdominal fat, have a higher risk of experiencing severe vasomotor symptoms. This could be due to increased endocrine dysregulation or the additional insulation of adipose tissue. However, the precise reasoning is not fully understood. 

Smoking

Both active and passive smoking may increase the risk of severe vasomotor symptoms. Many of the chemicals in cigarette smoke have anti-oestrogenic properties.

Negative Mood

Women who suffer from anxiety or depression tend to experience more severe vasomotor symptoms. There also appears to be a connection with childhood abuse or neglect and lower socioeconomic status (see chapter 5.2 Stress, Trauma, and Stress Resistance).

Diet and Exercise

The direct link between diet, physical activity, and vasomotor symptoms has not been confirmed. However, eating a balanced, calorie-controlled diet and engaging in regular physical activity can contribute to a healthy body mass index, which in turn could reduce the risk of vasomotor symptoms.

TCEAM Viewpoint

Traditionally, VMS (and menopause in general) have been associated with Kidney deficiency, especially Kidney yin deficiency. In reality, the aetiology of this symptom is usually far more complex.  

While Kidney deficiency is common among older patients, either Kidney yin or Kidney yang deficiency may predominate. However,  it is rare to see one without at least some degree of the other. Furthermore, other zangfu are frequently involved, as are qi and Blood deficiency or stasis. 

In TCEAM terms, VMS may be seen as a form of tidal heat effusion, or chaore. There are several different patterns of disharmony that may underlie tidal heat effusion, which we will discuss below. These may occur in combination with a variety of other underlying patterns. 

 Pattern Differentiation

1. Predominance of Kidney yin deficiency
2. Predominance of Kidney yang deficiency
3. Kidney and Liver yin deficiency with Liver yang rising
4. Kidney and Heart not harmonised
5. Yin and Blood deficiency
6. Spleen and Stomach qi deficiency
7. Yangming repletion
8. Summer-heat invasion
9. Blood stasis

Rebellious Qi in the Penetrating Vessel (Chongmai)

Around menopause, the qi of the chongmai can become destabilised, causing symptoms such as hot flushes and anxiety. This is not a clinical pattern in itself, but may occur alongside other patterns, including cold, heat, stagnation, and phlegm.

The chongmai has two branches originating from Yinhui REN-1. One branch descends to the feet while the other ascends to the face. Around the time of menopause, qi in the chongmai may become destabilised causing it to rebel upward and fail to descend. This can occur as a result of various excess or deficiency factors, including heat, cold, stagnation, etc. 

Clinical Manifestations

Feelings of heat in face, cold feet, headache, feeling of a lump in the throat, breast distension/pain, flutter in the chest or above the stomach, palpitations, slight breathlessness, sighing, chest tightness/oppression, abdominal fullness/distension/pain, irregular/painful/heavy periods, hypogastric fullness/distension/pain.

To make a diagnosis, at least three symptoms must be present at different physical levels (i.e. hot face, cold feet, and abdominal symptoms), in combination with anxiety.

Pulse: Firm and beating straight up and down in all three positions, from chi to cun, being most pronounced in the middle (guan) position. However, the precise quality will vary depending on coexisting excess and deficiency patterns, meaning that patients may present with a wide variety of pulses. 

Tongue: Variable, depending on coexisting excess and deficiency patterns.

Treatment Principle

Harmonise the chongmai, subdue rebellious qi.

Points

Juque REN-14

Zhangmen LIV-13

Zhongji REN-3

Qichong ST-30

Youmen KID-21

Dahe KID-12

Qixue KID-13

Gongsun SP-4

Neiguan P-6

Taichong LIV-3

Prescription

For cold: Wu Zhu Yu Tang

For heat stagnation: Zuo Jin Wan

For phlegm: Wen Dan Tang

For food stagnation: Bao He Wan