Sleep apnoea can encourage cancer growth

A new study has shown how patients who suffer from sleep apnoea may leave themselves open to encouraging the growth of cancer tumours.  The hypoxia caused by the condition results in blood vessel growth in tumours.
Sleep apnoea is a disorder whereby the patient has shallow breaths and pauses in breathing during sleep, which can last from a few seconds to a few minutes and can happen up to 30 times in an hour. This can be due to the airway becoming blocked or collapsing during sleep.  Risk factors include a small upper airway, smoking, alcohol use, being overweight and having a large neck. Many patients who suffer respiratory disease also find that they suffer from sleep apnoea, especially COPD patients as a large proportion of COPD patients still continue to smoke.
Previous studies have linked sleep apnoea to an increase of death from cancer but this recent study has made the mechanisms a bit clearer. It seems that the intermittent hypoxia (reduction of oxygen in the blood available to the tissue cells) suffered by the patient during episodes of sleep apnoea encourages mechanisms that result in tumour growth.  Mice that had tumours and experienced intermittent hypoxia (like with sleep apnoea) showed an increase in vascular progenitor cells and endothelial cells. These cells than can mature to create blood vessels in tumours. This increase in blood vessels within the tumour will allow the tumours to receive more oxygen and nutrients from the blood to encourage growth and for them to metastasise and spread throughout the body.
Also these mice showed an increase in levels of VEGF (vascular endothelial growth factor) which is a protein known to boost blood vessel formation.  Overall the team behind the study believe that the findings indicate that sleep apnoea may worsen the outcome for cancer patients.
Dr. Vilaseca says “patients suffering from obstructive sleep apnoea usually suffer from intermittent hypoxia at night. This work shows that intermittent hypoxia has the potential to promote the formation of blood vessels within tumours, meaning that the tumours have access to more nutrients.”
Prof. Arnulf Stenzi comments that the findings are remarkable and shows how oxygen deficiency can really influence the body in many ways and especially in this case with tumours. “It may be postulated that increased oxygenation of the blood may be the underlying mechanism why not smoking or giving up smoking, regular sport activity, reducing the body mass index (BMI) and other lifestyle changes that increase tissue oxygenation have a supportive beneficial effect on better outcomes in….cell cancer.”
Further studies will be carried out as it opens up the question as to whether this only happens during sleep apnoea episodes or whether it could happen during the waking day with patients who suffer from shortness of breath with respiratory conditions such as asthma and COPD. It could make it even more vitally important that patients who suffer from conditions where blood oxygen levels drop ensure they are monitored and take their medication and supplemental oxygen regimentally both day and night to ensure that they are not risking an increase in tumour growth. Cancer can go undetected and you may not be aware that you have it but allowing your body to become hypoxic could be encouraging tumour growth; whether malignant or benign and worsening the condition and your outcome.

How to sleep better during the summer months

Many who suffer with respiratory disorders also find it difficult to sleep at night, often suffering from sleep apnoea and requiring oxygen at night. Extremes of temperatures can affect your sleep and your health.

Sleep apnoea is caused when the upper throat muscles relax too much during sleep, cutting off or restricting the airway. These episodes, which also cause the oxygen level in the blood to drop, last from 10 seconds to a minute or longer. The brain registers the lack of oxygen and the individual wakes up just enough to open the throat and begin breathing again, starting the cycle over. Most of the time, individuals don’t remember these episodes in the morning, but they severely disrupt the restorative effects of sleep.
Being too hot or too cold can worsen the situation, resulting in disrupted sleep, low oxygen levels, worsening health conditions and drowsiness the following day. Many find using oxygen at night helps to maintain oxygen levels, minimises the frequency of waking up and prevents your respiratory problems from worsening, but if you’re too hot during the summer months you still need to be able to sleep soundly as sleep provides you with so many rejuvenating and healing properties.
The most important factor is the ambient temperature in your bedroom, this needs to be slightly cool in order to help keep your body’s core temperature lower. Otherwise it puts the body clock out of sync and you wont sleep properly. It’s better for it to be a bit nippy as you get into bed as your body will generate heat during the night from metabolism and trying to maintain your body’s core temperature at the correct level.
If you’re lucky enough to have an AC unit then use it, however for the rest of us there are some ways that can help to make sure you get a good night’s sleep.
1) Pillows
The head is the hottest part of the body so you want to keep it as cool as possible. Conventional pillows surround your head, trapping in the heat. A smaller, firmer pillow, although less comfy will allow more air circulation.
2) Fans
You can make a cheap version of an AC unit using these three simple household items – an electric fan, a large mixing bowl and some ice cubes. Place the ice cubes in the bowl, in the path of the airflow coming from the fan. The warm air causes the ice to melt, dispersing a cool breeze around the room.
3) Sleep like a Pharaoh
The so-called Egyptian method requires either a bed sheet or a towel large enough to cover your body. Soak the sheet in water, then put it in the washing machine on spin cycle -or just wring it out to stop any dripping. When you go to sleep, cover yourself with the damp sheet. This will keep you cool via latent heat, the same process that sweating uses to cool your body down.
4) Keep the sun out
The sun’s rays are far more powerful in the summer and keeping the blinds down stops the rooms heating up during the day.
5) Change what you eat
Usually when it;s hot you don’t feel like eating big meals anyway but remember that the larger the meal, the more metabolic heat you generate as your body breaks down the food. Try switching to salads, fruits and vegetables that the body can metabolise with less effort. If you cook a lot at home, switching to more raw foods will also mean less cooking, which means less heat being generated inside the house.
6) Location
You could try sleeping in a hammock, as being suspended in mid-air means that air flows all around your body, unlike a mattress which absorbs and reflects your body heat. Lower storeys are generally cooler than upper ones as heat rises. Finally, if all else fails, there’s always outdoors.
If you do use oxygen at night ensure there is air flow in the room and maybe use a dehumidifier, as the equipment may be generating heat while you are trying to sleep. Also check with your doctor if you are having trouble sleeping as they may adjust your oxygen flow rate settings if needed.
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