Millions of people are having trouble sleeping after the pandemic. For the past three days we’ve shared advice from consultant neurologist and sleep specialist Professor Guy Leschziner. Sleeping insomnia does not pose a danger to your health.
But the same can’t be said of sleep apnoea. Professor Leschziner will focus on the management and identification of the condition in the last part of the series.
Feeling tired all the time is a common problem — and the list of possible causes is endless: an underactive thyroid gland, diabetes, depression, cancer, shift work, anaemia, carbon monoxide poisoning… the list goes on.
One possible — if under-considered — explanation is sleep apnoea. As you sleep, it’s natural for the muscles in the walls of our throat to slacken a little.
This slackening can cause the airway collapse in certain people. You may snore, stop breathing repeatedly, or gasp for breath several times per night.
You will probably not realise you’re doing it — although your partner might — and the danger is that these multiple little awakenings are having an effect throughout your body.
Feeling tired all the time is a common problem — and the list of possible causes is endless: an underactive thyroid gland, diabetes, depression, cancer, shift work, anaemia, carbon monoxide poisoning… the list goes on
Being overweight is a risk factor for sleep disorder. Another sign is snoring, frequent trips to the bathroom at night. The kidneys are more likely to make urine when there’s a pause in your breathing.
A significant effect of sleep disorder is sleep apnoea, which can cause sleepiness throughout the day. This could lead to people falling asleep when they relax or get behind the wheel.
This tiredness doesn’t make sense as you think you slept all night, but you were actually having your sleep disrupted several times an hour.
With each obstruction, and every brief suffocation there’s a sudden surge in activity in your sympathetic nerve system (the part of the nervous that drives the flight-flight response), an increase in heart rate, blood pressure, stiffening of the arterial walls, and a decrease in oxygen level.
These physiological changes may lead to permanent high blood pressure over time. This can cause serious health problems such as stroke and heart disease.
The link also exists with concentration problems the next morning, which can be short-term cognition issues.
But there may also be a longer-term risk for the brain, of memory decline or worse, possibly Alzheimer’s. Although sleep apnoea has been strongly linked with obesity, this condition may lead to weight gain. We know for example that sleep apnoea can also affect the levels of leptin (a hormone that regulates appetite) and ghrelin (a hormone that regulates metabolism).
You will probably not realise you’re doing it — although your partner might — and the danger is that these multiple little awakenings are having an effect throughout your body, writes Prof Guy Leschziner
Separately, it’s also been shown that the temporary drops in oxygen levels and sleep disruption reduces the body’s response to insulin, the hormone that mops up sugar from the bloodstream for storage in the cells — this can lead to insulin resistance, the first step in the development of diabetes.
So, it is possible that sleep disordered breathing can lead to increased calorie intake and more calories being processed.
There are effective ways to treat the condition once it is diagnosed. You can lose weight, as well as not sleeping on your stomach. Oral devices are also helpful to keep the lower jaw open and the airway open.
Continuous positive airway Pressure (CPAP) is used for the majority of cases. The machine pumps pressurised air through a mask that is attached to the face. This keeps the airway open during nighttime sleep. CPAP can improve brain function, mood, and sleepiness. It also reduces blood pressure.
Patients suffering from severe sleep apnoea can now have an electronic device placed in their necks to stimulate the nerve that retracts your tongue during sleep.
PS. PS.
One of the questions I am so often asked is ‘how much sleep is enough?’. I’ve held off writing about this until the final part of my series because, as you will have seen over the course of the last three days, the answer is: whatever is enough to leave you feeling refreshed the next day. And that is what the practical steps, including CBTi, the therapy I explained in Sunday’s paper, are about — not aiming for a set amount of hours asleep.
Of course, seven to eight hours is the received wisdom — but this is the average — and who is to say that you are average?
There are plenty of outliers — a few people can thrive on five hours a night, while others still struggle with closer to nine hours of unbroken sleep.
Our sleep requirements change as we age. Two-thirds sleep is normal for a newborn, but by the time we reach adulthood, our sleep needs will change. We sleep an average of six and a-half to eight and a-half hours each night, although these numbers are only estimates.
The stages of sleep are divided into multiple phases. They can be repeated four to five times per night in 90 minute cycles. As we drift off, we enter stage 1 ‘drowsy’ sleep, then stage 2, known as light sleep, when brain activity slows further but we might still easily be nudged awake.
Deep sleep is Stage 3. It usually takes about 30 minutes to enter this stage. During this stage our brainwaves slow considerably, and this is when the body carries out repairs and the brain is thought to do most of its ‘clearing out’ of waste products.
Rapid eye movement (REM), which is the last stage we enter, tends to take between 60 and 75 minutes.
Here, the brainwaves look highly active — a little like when we are awake — and it is then that we tend to dream. Adults have more deep sleep during the first part of the night, and less REM sleep at the end of the second.
As babies, we spend around half of our slumber in REM sleep, while in adults it’s 15 to 25 per cent, gradually falling as we approach old age.
In adulthood, the proportion of deep sleep decreases to around 15 to 25%, while it drops slightly in seniors, when Stage 1 or 2 sleep is usually in place.
With all that said, the right amount of sleep for you is however long it takes for you to wake in the morning feeling refreshed, without relying on an alarm, not feeling sleepy during the day or like you need to ‘catch up’ on sleep at weekends or in time off, and feeling ready for bed at a regular time — with no trouble dropping off.
Professor Guy Leschziner’s new book, The Man Who Tasted Words: A Neurologist Explores the Strange And Startling World Of Our Senses is published on February 3 (Simon & Schuster, £16.99). See next week’s Good Health for an exclusive extract.