Podcast information | Dr Louise Oliver The

A missing jigsaw piece in perimenopausal and menopausal care

Perimenopausal and menopausal information frequently discusses the effect of changing hormones levels on skin, brain, heart, bones, muscles etc however the effect on breathing is often overlooked.

Hormones affect how we breathe

How we breathe affects our health and well-being

Breathing is generally an unconscious process, however this does not mean it is automatically efficient.

I am promoting the 3 A’s approach:

Aware – raising awareness of how breathing is altered by hormones, how this can lead to inefficient breathing and symptoms of inefficient breathing.

Assess – offering an opportunity for women to assess their breathing efficiency.

Action – encouraging and empowering women to improve their breathing efficiency.

Breathing may be a large or small piece in your perimenopausal/ menopausal care jigsaw – I encourage you to read on to find out more.

Aware

Women generally have a smaller airway, ribcage size, lung volume and a shorter diaphragm than men. In addition, the movement of the ribs during an inhalation is different in women compared to men. (1) All these factors impact how easily air enters and leaves the female body.

A large population-based study showed lung function declined more rapidly among perimenopausal and menopausal women. This decline was greater than the normal expected deterioration in lung function related to aging. The study noticed the decline appeared to increase difficulties breathing in compared to breathing out. (2) It is known there is an increased loss of muscle around the menopause (3) but how often do we discuss muscle loss from the breathing muscles and perform breathing muscle exercises to strengthen these muscles?

Although the exact mechanism is not clear, studies have shown an increased risk of sleep disordered breathing after menopause. (4) Sleep disordered breathing (SDB) refers to a wide spectrum of sleep-related conditions including increased resistance to airflow through the upper airway, heavy snoring, marked reduction in airflow (hypopnea), and complete cessation of breathing (obstructive sleep apnoea = OSA) (5)

The Wisconsin Sleep Cohort Study demonstrated that there is a 3 times greater risk of moderate or worse OSA in post-menopausal women compared to pre-menopausal women. (4) Women with OSA are less likely to report snoring or witnessed gaps in breathing (apnoea) but are more likely to complain of daytime fatigue, lack of energy, insomnia, morning headaches, mood disturbance and nightmares compared to men. (6)

More research is needed in how hormonal changes affect breathing however it seems female hormones generally have a protective effect on the airway and drive to breathe. It is thought the female hormones increase the tone of the upper airways muscles preventing airway collapse during sleep. Therefore, the reduction in the female hormones after the menopause may be the reason why the upper airway is more likely to collapse and increases the risk of OSA. (6)

Progesterone acts as a powerful respiratory stimulant (which means it increases how fast the individual breathes) by increasing the body’s response to low oxygen and high carbon dioxide levels. This could help the airway open up but conversely the faster breathing rate could cause a vacuum effect leading to airway collapse. Also, if the faster breathing rate leads to a reduction in carbon dioxide levels this can trigger the body to have pauses in the breathing to allow the body to increase the levels back to normal.

Furthermore the change in body fat distribution around the menopause can lead to increased body mass index (BMI), waist circumference, and neck circumference which are all associated with higher severity of OSA. (4)

With all these changes the efficiency of breathing can deteriorate as women transition through to menopause. I developed snoring in my perimenopause despite a healthy weight and running three times a week. HRT helped many of my symptoms but did not improve my snoring and sleep. I improved my breathing efficiency which stopped my snoring, improved my sleep, and made running easier.

Autonomic nervous system

To understand why breathing is so important and how we can improve our breathing efficiency I would like you to understand the autonomic nervous system (ANS). Your body is amazing. From moment to moment without conscious control your body is making fine adjustments to your blood pressure, pulse, temperature, amount of saliva, gut digestion, muscle contraction, pupil size etc. There are two main parts to the ANS: the fight, flight, freeze system (sympathetic nervous system) and the ‘rest & digest’ or ‘feed & breed’ system (parasympathetic nervous system).

The fight, flight, freeze system (sympathetic nervous system) gets a bad rap in the media. We should be very grateful for this system. The fight, flight, freeze system has been developed to keep us safe and helped our species survive and develop. It makes you the best version of yourself IF ACTIVATED OCCASIONALLY. When this system is activated, your whole body reacts so it is ready to respond to danger – e.g. your muscles will contract, sugar pours into your blood stream, your pupils widen, cortisol (steroid) and adrenaline increase in the blood, you are more likely to breathe fast, with an upper chest, take larger amounts of air, through an open mouth and breathe irregularly. This means you are ready to fight, run or play dead to help stay safe. This is a perfect response to a true threat but not to an e-mail from your boss, getting stuck in traffic etc. View the fight, flight, freeze system as first gear or an accelerator in a car – you need this system to get out of trouble. However, if you constantly accelerated or drove in first gear the car will start to breakdown. We therefore want this system to turn on only when a true threat is present.

The wonderful news is we have an opposite system: the ‘rest & digest’ or ‘feed & breed’ system (parasympathetic nervous system). This should be regarded as the brake or driving in fifth gear and should be our default mode. In this state our body doesn’t feel under threat, feels safe, can digest food and libido is present. Breathing in this state should be slow, gentle, through the nose and driven by the diaphragm.

The ANS without our conscious control should drive our body with two feet. One foot able to press the brake and one foot for the accelerator. The body making gentle flexible adjustments to the accelerator and brake according to the circumstances. This flexibility in the ANS is reduced in chronic pain (7), long covid (8) and chronic health conditions such as heart disease (8) and diabetes (9). Breathing re-education can improve the flexibility of your ANS, turn down the ‘fight, flight, freeze’ system and improve the amount of time spent in the ‘rest and digest’ system. (10)

There is evidence the threat detection centre of the brain (the amygdala) has a (nerve) neuronal connection to our breathing (respiratory) centre monitoring for changes in our breathing. (11) The amygdala also has roles in emotion, learning and reward. It is thought this that this neuronal connection has developed through evolution to improve survival, for example if our breathing becomes fast, heavy and uses the upper chest the amygdala notices this change, perceives it as a threat to the body and sends a signal to the body to activate the fight, flight, freeze response. Therefore, if breathing during sleep is hard, fast, and irregular the amygdala will try to wake us up as the body is responding to a perceived threat which unfortunately is likely to lead to a light sleep or regular waking. A slow, regular, gentle breathing pattern at night is more likely to improve sleep quality.

If an individual struggles to go to sleep changing to a slow, regular, gentle breathing pattern sends a signal to the brain to turn on the ‘rest and digest’ system aiding transition from wakefulness to sleep.

Symptoms of inefficient breathing

In 1975 Dr Lum a Respiratory Consultant at Papworth & Addenbrookes Hospital in Cambridge published a paper that described 700 patients who had been assessed but 82% had no detectable pathology and their symptoms were largely or entirely related to breathing inefficiently. (12) Table 1 in his paper lists the main symptoms observed by a general physician in 270 cases. (12) Dr Lum stated ‘symptoms may show up anywhere, in any organ, in any system’ (12) The symptoms included palpitations, dizziness, muscle pain, anxiety, exhaustion, sleep disturbance – common symptoms of the perimenopause and menopause. I would encourage anyone with these symptoms to assess their breathing efficiency (see below) in addition to seeing their health practitioner to exclude any other underlying physical cause.

Consequences of sleep disordered breathing:

Sleep disordered breathing has consequences which affect health and well-being (4):

Fatigue – SDB makes it less likely the ‘rest and digest’ system is activated whilst asleep. Also, SDB uses more of the body’s energy requirement as the breathing pattern is less efficient.
Reduced concentration or ‘brain fog’ - SDB alters the depth of sleep therefore affecting the ability of the brain to think.
Raised blood pressure – often individuals with SDB do not use the nose to breathe at night. Nasal breathing makes it much more likely the diaphragm is used. When the diaphragm is used to breathe less work is required by the heart as the outer covering of the lower heart is attached to the diaphragm. The diaphragm acts as a ‘second heart’ pumping the blood around the body resulting in lower blood pressure and resting pulse. Mouth breathing does not fully utilise the ‘second heart’.
Increased risk of heart attack, heart failure and stroke – due to higher blood pressure and SDB maintaining the fight, flight, freeze system whilst asleep.
Increased risk of anxiety and depression – research has shown there is an association between OSA and depression. Persistent activation of fight, flight, freeze system fuels anxiety.
Increased risk of accidents – due to fatigue. Unfortunately, some accidents are fatal or life changing.
Increased risk of memory problems – MRI studies of the brain have reported damage of the hippocampus (area of the brain involved in memory) (13). Autopsy brain tissue from people with OSA found as OSA severity increased, the amount of damage to the hippocampus increased. (14)
Increased weight gain and diabetes – persistent activation of fight, flight, freeze system leads to higher glucose levels and subsequent increase in gaining weight around the tummy area.

Assess

Effective breathing is through the nose, slow, gentle, the exhale is longer than the inhale, there is a short pause after the exhale, and it is driven by the diaphragm (lower ribs expand sideways on the inhale). Over the next week check in with your breathing intermittently to assess whether it matches this description, including when you are distracted on the computer or watching the television.

Breathing inefficiency (dysfunctional breathing) lacks a rigorous definition and a clear method of assessment. Kiesel and colleagues (15) explored different assessment methods which led to them proposing a breathing screening procedure consisting of measuring breath hold time (BHT) and answering four questions. This does not diagnose dysfunctional breathing however it is a useful tool to indicate if you may benefit from improving your breathing efficiency.

Why would measuring the time you can hold your breath indicate inefficient breathing? At some point after you start holding your breath your brain sends a signal to breathe. Frequently individuals believe this is due to their oxygen levels dropping however this is not the case. By holding your breath you stop breathing out carbon dioxide, so the levels of carbon dioxide rise. There is enough oxygen in your lungs and blood to maintain oxygen levels during a breath hold of this type. You have receptors in your body that have a specific sensitivity to carbon dioxide that is personal to you. When the carbon dioxide level reaches your sensitivity level your body will send a signal to breathe, and you will feel ‘air hunger’ which is a feeling you either need to take more air in or you are not getting enough air into your body.

Measure your breath hold time (BHT)

Check this after waking and before eating.

Sit upright.

Keep your mouth closed throughout the measurement.

Take a small silent breath in through your nose.

Allow a small silent breath out through your nose

Hold your nose with your fingers to prevent air from entering your lungs

Using a stopwatch record the number of seconds until you feel the first involuntary muscle spasm – you will feel this as a contraction in the neck or diaphragm (bottom of your ribs). This is your brain sending a signal to your body to breathe as you have reached your carbon dioxide sensitivity level. We are testing comfortable breath hold time not testing willpower therefore your breathing should be calm afterwards.

Do you notice any of the symptoms below often or very often:

Do you feel tense?

Do you feel a cold sensation in your hands or feet?

Do you notice yourself yawning?

Do you notice breathing through your mouth at night? (this may need to be assessed by another person. A very dry mouth in the morning, noisy breathing or snoring is suggestive of this)

If you scored less than 25 seconds and answered often or very often to one of the questions I would encourage and empower you to take action to improve your breathing efficiency.

Action

Improving breathing efficiency with breathing re-education (18) (19) consists of two aspects:

The first is ensuring the air way is open, strong and combined with nasal breathing.

The second is ensuring the amount of air an individual is breathing matches what we need, we are using the correct breathing muscles and the speed of breathing results in synchrony between the heart and lungs.

I would like you to think of breathing like drinking a thick milkshake through a paper straw. If I offered you a choice of a thick, thin, straight or bent paper straws choosing the thick, straight paper straw would increase your chance of drinking the milkshake with ease. Therefore, it is important we work to ensure our airway is as open as possible.

Ensuring the airway is open, strong and combined with nasal breathing

Tongue position

You may be surprised to hear the position of the tongue is crucial to keeping the airway open. The back of the tongue forms part of the airway. If the tongue is in the correct position, it opens the airway. The correct position for the tongue is flat against the roof of the mouth, not touching the front teeth, lips sealed and not clenching your teeth. If the mouth is open the tongue naturally sits in the lower part of the mouth and narrows the airway. If your tongue is not normally in this position it will take time to build up the strength in your muscles of your face, upper airway, and tongue. Find a way of reminding yourself about tongue position when doing your everyday activities e.g. filling up your water bottle, putting on the kettle, walking up the stairs etc.

Throat (oropharyngeal) exercises (16)

As I have highlighted it is thought the tone of the upper airways muscles decreases after the menopause. This could cause increased resistance to air passing through the upper airway or the throat to vibrate (resulting in snoring) or collapse (resulting in OSA). We can decrease the chance of this happening by practising throat (oropharyngeal) exercises to improve muscle strength. Teaching these exercises is one of the roles of a myofunctional therapist however this is not available within the NHS. Mr Vik Veer is an ENT Consultant and lead for the Sleep Surgery department at the Royal National ENT Hospital, London. He has created a YouTube video describing throat (oropharyngeal) exercises which have been shown in studies to improve snoring and sleep apnoea. I would encourage you to watch the video several times and when you are confident you will be able to practice these quickly without watching the video. Tag this to an everyday activity so you don’t forget to practice once daily e.g. before brushing your teeth at night. Be patient building muscle strength takes time.

Nasal breathing

The next step in effective breathing is breathing should ONLY occur through the NOSE. This includes at rest, during exercise and whilst sleeping. The nose is designed to pressurise, warm, moisten, and filter out impurities and invaders from the air we breathe – the mouth is not. Please let this information sink in ……despite all my medical training this was a wake-up moment for me when I suddenly thought if I mouth breathe, I inhale viruses, bacteria, pollutants, pollen straight from the environment into my lungs without involving the first line defence of my nose? It makes no sense at all. The mouth has no role in breathing. Also if you breathe through the mouth, it brings dry, cold, unpressurised air into the lungs which can trigger spasm of the breathing tubes in the lungs (exacerbating asthma or causing wheeze) or trigger the cough reflex.

One study (17) looked at individuals with OSA whilst under sedation and whether breathing through the nose or mouth whilst asleep affected the percentage of time with an oxygen saturation less than 90% (this level is too low). The individuals mouth breathing spent 36.41% of the time with their oxygen levels less than 90%, those breathing with mouth and nose were 15.97% and those nasal breathing 5.76%. I appreciate this study is in individuals with OSA under sedation however it highlights nasal breathing is less likely to cause a drop in oxygen levels whilst asleep. Remember if the mouth is open the tongue is in the bottom of the mouth compromising the airway. I came across an xray picture by an organisation called HealthyStart® comparing the airway size with the mouth open and closed. I have found the xray is worth a thousand words. When individuals observe the xray, they can see the compromised airway with an open mouth, and in my experience helps them understand the importance of nasal breathing.

Teaching your body to have the mouth closed in the day will make it more likely you will nasal breath at night however if you are mouth breathing at night you need to reteach your body to nasal breath at night. There are various products available to keep the mouth closed whilst asleep. The product I have used is called MyoTape® that can help you retrain your body to nasal breathe at night. MyoTape® does not cover the mouth. Instead it placed around the mouth and gently brings the lips together with a light, elastic tension that helps to maintain lip closure and nasal breathing. It is sensible to get used to wearing the product during the day and when you are ready start wearing it at night. Do not use this product if under the influence of alcohol or sedative drugs. It takes around 3 months of daily use to retrain the nerve circuits, so this becomes a natural unconscious habit. Getting the mouth closed at night can lead to a profound improvement in energy levels and concentration.

Ensuring the mouth remains closed whilst asleep will stop mouth snoring however some individuals may still nasal snore. For many individuals nasal snoring can be eliminated by restoring nasal breathing during wakefulness and sleep, increasing breath hold time to above 20 seconds, reducing breathing volume to what the body requires, using the correct breathing muscles and slowing the speed of breathing. If nasal snoring continues, I recommend seeing a dentist or myofunctional therapist who has experience in assessing and treating the long term effects of mouth breathing on the dental arch and therefore airway size.

Breathing matches what the body requires, using the correct breathing muscles and the speed of breathing results in synchrony between the heart and lungs

If we return to the milkshake and paper straw analogy, we have ensured the paper straw (airway) is as open and as strong as possible. Now we need to look at the volume of milkshake coming through the straw. If we stuck fast and hard to drink a large volume of milkshake it is much more likely the paper straw (airway) will collapse. However, if we suck slowly and gently, we are able to drink the milkshake without the straw collapsing. Therefore, we need to look at how much air we are breathing. Living in a modern-day society makes it more likely individuals breathe in excess of what their body requires resulting in over breathing. In my clinical and personal experience wearing masks during the pandemic and COVID infection has further increased over breathing. Breathing uses a proportion of the energy requirements of the body therefore over breathing results in using up more energy than is needed and can lead to symptoms described by Dr Lum.

I want to dispel a myth that we need to take bigger breaths to take in more oxygen. 75 percent of the oxygen you take in is exhaled during rest. Even during physical exercise, when the muscles need a much greater supply of oxygen, as much as 25 percent of inhaled oxygen is exhaled. The issue is not getting oxygen into the lungs it is getting the blood cells to release the oxygen to our cells. Oxygen doesn’t dissolve very well in blood, so it is carried bound to haemoglobin in our blood cells. What you want is to increase the rate at which haemoglobin in the red blood cells releases oxygen to the cells. How do you do that….carbon dioxide. Carbon dioxide in the environment causes global warming but, in our body, it helps release oxygen to the tissues. When performing the breath hold time, I was testing your sensitivity to carbon dioxide. I asked you to hold your breath after an exhale. Carbon dioxide was building up and you let go when your muscle caused an involuntary muscle contraction to breathe. A breath hold time of less than 25 seconds suggests you have become sensitive to the build-up of carbon dioxide however you can train yourself to become less sensitive. A breath hold time of above 40 seconds is ideal however for every 5 second improvement in your breath hold test you will feel benefit. Please note the breath hold time is just a measurement and not a breathing exercise. As you become less sensitive to carbon dioxide your haemoglobin will release oxygen more easily to your cells and you will breathe slower and gentler, feel less breathless, and exercise becomes easier. In addition, carbon dioxide strengthens the nerve which controls the ‘rest and digest’ system therefore decreasing sensitivity to carbon dioxide improves mental health. Carbon dioxide also opens up blood vessels therefore improving circulation in the body. (12)

I would normally spend 5 sessions helping someone to re-educate their body to breathe effectively as there is a lot to learn and needs to be adapted according to the breath hold time of the individual and their medical history. A very gentle approach is required if the breath hold time is less than 13 seconds. In my experience it is more beneficial to begin with breathing exercises that reduce the volume of breathing to the requirements of the body. Naturally as this happens the correct breathing muscles start to be used and the rate of breathing decreases.

I have found if individuals with a low breath hold time begin with ‘belly’ breathing (beware it is possible to ‘belly’ breathe and not actually move the diaphragm) and/ or focusing on breathing at 6 breaths a minute they tend to over breathe which can exacerbate or cause the symptoms described by Dr Lum. I would recommend speaking to your health professional if you still have symptoms of sleep disordered breathing after 3 months of working on improving your breathing efficiency.

I run functional breathing programmes for the perimenopause and menopause which teach individuals how to improve breathing efficiency. Please see this page.

My 3 top tips

I want women to be aware that hormones affect how we breathe and how we breathe affects our health and well-being. Improve knowledge on breathing e.g. reading books and watching YouTube videos with James Nestor and Patrick McKeown.
I would like women to consider assessing their breathing efficiency.
I encourage and empower women to act to improve their breathing efficiency by dedicating time over a number of weeks and months. Over time they will not need to spend as much time on the exercises, it becomes part of how they naturally breathe, and they develop a method to self-regulate their autonomic nervous system.

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