TAKING YOUR BREATH AWAY

Nothing is more guaranteed to sink the heart of the doctor opening a patient’s notes than seeing the acronym TATT, which stands for “tired all the time”. For the list of possible causes of TATT is almost endless: underactive thyroid gland, diabetes, depression, cancer, shift work, anaemia, carbon monoxide poisoning; the list goes on.

It is also incredibly common. Working out if there’s a serious underlying issue can be like looking for a needle in a haystack.

One possible — if under-considered — explanation is sleep apnoea. This is a sleep disorder in which someone briefly, but repeatedly, stops breathing during the night. Unsurprisingly, this disturbs sleep, although the person may not realise it, and over time sleep apnoea has serious consequences for health, including an increased risk of stroke and heart disease.

We are in a sleep apnoea epidemic. A recent Swiss study suggests that up to one in two men and one in four women have

problems with their breathing at night. When I meet Maria, who had been referred to our sleep clinic, I imagine that TATT has been scrawled in her medical notes by her GP. In her 40s, juggling motherhood and a job in healthcare, she tells me: “I was just exhausted all the time. I never felt well and thought maybe it was my thyroid or anaemia. I went to the doctor repeatedly for blood tests.”

Sheer exhaustion was impacting all aspects of her life. She’d developed eczema — after a lifetime of clear skin — and was struggling to shift a little extra weight. Exercising felt impossible. It was also having a significant effect on her relationship with her husband.

“Any little bump in the road was like the worst thing that had happened to anybody ever, and I’d fly off the handle,” she explains. “I’m quite a cheery person by nature but my sense of humour went.”

Fuelled by coffee, Maria would pinch herself under the table in meetings to make sure she didn’t doze off. If she wasn’t working, she would take her children to school, come home and get back into bed, setting her alarm for 20 minutes before she had to pick them up again. “I didn’t even have the energy to read a book because I’d be asleep before I got to the end of the page,” she tells me. “I really did feel like I was falling apart.”

As I listen, I am struck by the lengths that Maria went to in an attempt to improve matters. “I was doing everything I could,” she says. “I was trying meditation, mindfulness, yoga. I was trying to change my diet. I even changed my job.”

It was 18 months before sleep apnoea was considered. That’s when she was sent to our clinic. Normally, as you drift off, the countless small muscles of the walls of your airway slacken a little.

However, if your airway is narrow enough or becomes sufficiently floppy, it can become partly or completely obstructed.

This collapse results in oxygen levels falling and the heart rate increasing, disrupting your sleep in order for muscle tone to return briefly to the airway, allowing you to breathe again. This can happen 10, 20 or even — in rare cases — as often as 100 times an hour.

The rates of sleep apnoea have increased in parallel with our girths and neck circumferences. Fat around the neck makes the airway narrower and more likely to collapse, while fat on the chest increases the effort of breathing.

But sleep apnoea may also run in families and is often related to the shape of the airway. A large tongue, recessed lower jaw and large tonsils can cause narrowing, too. As well, people of South-East Asian ancestry, and older people (possibly because of changes to muscle) are more at risk.

Snoring can be a warning sign — but it is not just a snoring problem. Having your sleep disrupted several times an hour unsurprisingly results in excessive sleepiness during the day — and this can be extreme. At our centre, we’ve had countless patients whose sleep apnoea has come to light after they have fallen asleep at the wheel of their car and had an accident.

Sleep apnoea has costs beyond tiredness, however. Over time, physiological changes can lead to permanently high blood pressure and, in turn, the serious problems it causes such as heart disease and stroke. There is also a link with cognition problems such as concentration, and possibly long-term, with Alzheimer’s disease.

There are various treatments for sleep apnoea. Weight loss helps and, for some patients, options include not sleeping on their back and oral devices to hold the lower jaw forward and open up the airway. For serious cases, an electronic device can be implanted in the neck to stimulate the nerve that retracts the tongue in sleep.

At the time, however, there was really only one choice for Maria — CPAP, or continuous positive airway pressure. This device consists of a face mask attached to a small machine that pumps out pressurised air that keeps the airway open during sleep.

Benefits of CPAP on cognitive functioning, mood and sleepiness in patients with sleep apnoea have clearly been demonstrated. We also know that CPAP results in an improvement in blood pressure and endothelial dysfunction. The research is less clear on whether it can reduce the risk of longer-term health problems.

Maria, however, has persisted with the mask and machine. The short-tempered, exhausted Maria has been replaced by someone smiley, energetic and able to cope with a busy home and working life.

She tells me her sleepiness has completely resolved. “I don’t love the mask,” she says. “But the effect it has had on my life has been so positive. I used to just come home, switch on the TV and be asleep within half an hour — but I can focus again now.”

Dr Guy Leschziner is a consultant neurologist and sleep physician in London. Adapted by Jennie Agg from The Nocturnal Brain: Nightmares, Neuroscience and the Secret World of Sleep by Dr Guy Leschziner, Simon &