Hot Flashes 101
Written by: Dr. Madeleine Clark, ND MSCP
Hot flashes, or night sweats, medically known as vasomotor symptoms (VMS) are one of the most commonly reported symptoms of menopause. It is so common that by 2025, 1.1 billion women around the world will experience these symptoms related to menopause.
What is a vasomotor symptom/hot flash?
Typically they are characterized as a very sudden, intense sensation of heat in the upper body - specifically involving the chest, neck, and face. They vary in length - potentially lasting from 1 to 5 minutes and may also include sweating, chills, heart palpitations, and anxiety. Night sweats are hot flashes that occur during sleep and cause you to wake up.
Who gets hot flashes?
Some research has shown up to 60-80% of women experience VMS going through menopause, but the rates may depend on racial and ethnic groups. Typically black women, followed by Hispanic women are the most likely to experience VMS. It is unclear why these differences persist.
Do you experience hot flashes during the entirety of menopause?
How many hot flashes you experience changes throughout menopause. Typically 20-40% of women may experience hot flashes before perimenopause, which may increase to 60-80% during perimenopause, and a portion of these people may continue to experience hot flashes in post-menopause. On average, women may experience hot flashes for up to ten years, with some studies indicating that hot flashes can begin 7 years before the final menstrual period, and persist for 4.5 years afterwards.
What are the risk factors for hot flashes?
The following risk factors have been identified for hot flashes. We don’t fully understand why some of these
Socioeconomic factors
Patients with lower socioeconomic position and lower education attainment report more VMS.
Obesity
Patients with a higher BMI are more likely to report VMS, especially if this is due to a higher percentage fat tissue, and if the location of this fat is in the mid section.
Health behaviours
Cigarette smoking, higher alcohol intake, and high-fat and high sugar diets are associated with increased risk of VMS.
Hysterectomy
Patients who have undergone bilateral oophorectomy (where both ovaries are removed are more likely to experience more frequent and severe menopause symptoms.
What causes hot flashes?
For a long time we thought that the declines in estrogen at the level of the ovary were responsible for hot flashes - however all women experience declines in estrogen, but not all women experience hot flashes. Depending on how steep this initial decline in estrogen is, it may be associated with more severe VMS.
Another theory of why hot flashes occur is though to be due to changes related to our thermoregulatory system, and that a hot flash is an acute events in which our body is trying to dissipate heat. We think that the thermoregulatory zone is narrowed in menopausal women - and this system is controlled by a variety of brain areas, neurotransmitters and blood vessels - which may all be involved in the response.
Genetics may also play a role - as changes to neuron receptors named Kisspeptin-neurokinin B dynorphin, have been found in animal studies to be responsive to estrogen and that their expression changes with the withdrawal of estrogen.
Finally, we believe serotonin might also be contributing to hot flahses, as medications that increase the availability of serotonin have been shown to improve the number and severity of hot flashes. Serotonin is known to play a role in mood, anxiety, sleep, sexual behaviour and thermoregulation (all of which can be altered in them menopause transition!)
Nervous system
We know there is a complex interaction of the nervous system involved in hot flashes. This includes both our central nervous system and our sympathetic and parasympathetic nervous system. This may be partially why some treatments, such as hypnotherapy are helpful for treating VMS.
Hypothalamic-pituitary-adrenal axis (HPA axis)
Our HPA axis controls our cortisol and physiological response to stress. It’s thought that this may be dysregulated in some women with VMS.
Endothelial dysfunction
Endothelial linings are the inner parts of our blood vessels, and injury and dysfunction is one of the beginning events that can lead to atherosclerosis (the buildup of plaque in our arteries) and predict cardiovascular events (heart attacks & stroke). Endothelial changes may contribute to hot flashes and cardiovascular health is linked.
Inflammation & Clotting
VMS may be linked to increased inflammatory action in our bodies and and blood cell clotting. Inflammatory markers such as interleukin-8 or tumor necrosis factor-alpha may be increased in patients who experience hot flashes, but the mechanisms are still being discovered.
Treatment
There are a variety of treatments available for patients experiencing VMS.
Hormone Replacement Therapy (HRT)
Hormone replacement therapy (HRT) is considered the first line treatment for VMS. Hormone replacement therapy can reduce the severity and frequency of VMS, as well as provide other benefits in menopause. It may not be right for everyone, book a complimentary meet and greet appointment with Dr. Madeleine Clark, ND to learn more about your options.
Medications
Other medication options such as SSRIs, Gabapentin, Clonidine and Oxybutyin have been found to be beneficial to different degrees for VMS. Depending on the symptom picture and suitability for HRT, these options may make sense to discuss with your healthcare provider.
Lifestyle interventions
Cognitive Behaviour Therapy (CBT)
CBT, is a mind body and therapy technique that has been found to be useful to improve VMS symptoms. Research has shown it is helpful even when administered in group or self-help formats, and had extended benefits beyond improving VMS symptoms like improvements in mood, quality of life and overall functioning. This is a great option for patients who are also experiencing mood symptoms, patients who are in need of additional support for their VMS alongside their medications, or for patients where HRT is not a good option.
Hypnotherapy
Hypnotherapy is another mind-body technique that has shown strong promise to alleviate VMS symptoms - with research showing benefit in breast cancer survivors and post-menopausal women. It has been studied against venlafaxine (a medication used for mood and VMS) and found it works to a similar degree. Hypnotherapy is gathering more evidence for many health concerns including IBS and commonly used in labour. You can read more about hypnotherapy on our blog here.
Mindfulness-based stress reduction (MBSR)
Mindfulness-based stress reduction focuses on decreasing stress through acceptance of thoughts and feelings, mindfulness and gentle stretching. There is limited evidence that shows these techniques can help VMS, but they have been shown to improve quality of life, anxiety, sleep and perceived stress.
Weight loss, Physical activity & Yoga
No evidence has found that weight loss, physical activity or yoga can meaningfully improve VMS. Weight loss earlier in the menopause transition may help VMS - although this might be related to the fact that VMS are often worse with increased weight. Physical activity has many benefits for health, but does not improve VMS, and yoga can reduce insomnia symptoms, but does not show meaningful change to improve VMS.
Dietary interventions
Soy foods have been looked at for improving VMS, but the evidence is mixed. Some research concluded that supplementation with soy isoflavones, which also included 15 grams of soy protein, led to a significant decrease in the number of hot flashes per day. However these impacts may take time before they are clinically relevant - with research pointing to approximately 13 weeks of consistent intake to show a half benefit for VMS, and 48 weeks for soy isoflavones to have a maximal effect of around 80% improvement. This compared to standard HRT treatment for VMS that took 3 weeks to show benefit in hot flash symptom frequency and severity.
Soy protein can be a healthy plant based protein and element of diet throughout this time.
Research on the benefit for acupuncture in reducing VMS is conflicting. Some papers have indicated that acupuncture may reduce hot flashes and night sweats, especially in breast cancer survivors. However, the results have been inconclusive. This may be an option for patients to try if they do not suit HRT, but it is always helpful to discuss with a practitioner your various options as acupuncture may require multiple appointments. Book with one of our acupuncturist to learn more.
Next Steps
If you’re experiencing hot flashes, there are many options to explore. Book a complimentary meet-and-greet appointment with Dr. Madeleine Clark, ND MSCP, to discuss personalized care.