- When you’re not feeling rested and refreshed after a night’s sleep — whether because you got in too few hours or you woke up often during the night — your thinking is fuzzy, your reaction time drops and you feel sluggish at work.
- But more and more research shows that sleeping poorly affects almost every function in our body — from heart health to mental health and body weight — which makes not sleeping well a big public health worry, experts say.
- Today, on World Sleep Day, we bring you insights from two experts whose work looks at how South Africans can be helped to sleep better.
In today’s newsletter Linda Pretorius tells you why counting sheep could be bad for your health. Sign up.
Blood pressure climbing? Putting on weight? Feeling lonely, down or grumpy? Battling with sniffles and colds often?
Research says these things might have a common link: sleep — or rather, not sleeping well.
In a large survey in the United States (US), about a third of adults reported getting too little sleep already 10 years ago; one in 10 operated on five hours or less a night. About one in 20 people said they had dozed off while driving during an earlier round of the survey.
These are big numbers of people — and it has big implications for public health across the world.
Which is why World Sleep Day is marked on our calendars every year on the Friday before the March equinox, a time when day and night is about equally long everywhere on Earth.
Scientists have known for a long time that we don’t perform well without getting proper shut eye. Our productivity drops, we make poor decisions and we struggle to concentrate. More and more, though, science is starting to show that how well or how much we sleep affects our whole body’s health. It’s no longer “an annoying interference, a wasteful state that you enter into when you do not have enough willpower to work harder and longer”.
But exactly why this is so, how it works and how to treat sleep problems have been almost as elusive as getting to the final number of sheep you’ve been counting for (seemingly) hours at night.
Pinpointing a sleep disorder is nebulous, though, because “doctors that come out of medical school never really engage with sleep and sleep disorders”, Alison Bentley, a sleep doctor at the Restonic Ezintsha Sleep Clinic at the University of the Witwatersrand, told Mia Malan in Bhekisisa’s monthly TV show Health Beat. “They might not know patients have sleep problems, because they’re not asking those kinds of questions.”
Research from the US also shows that how well people sleep is linked to whether they earn enough money, have good education or whether they live in rural areas or a city. Yet, for people who depend on the public health system — more than three-quarters of South Africans — getting a sleep disorder diagnosed is out of reach.
But, says Nomathemba Chandiwana of the Ezintsha Research Centre, “sleep medicine should not be elitist medicine”, which is why they are looking at cheaper ways to treat sleep disorders.
Here’s more from these two experts about getting sound sleep, whoever you are.
Mia Malan (MM): How many hours of sleep should we have per night?
Alison Bentley (AB): It’s different for each person. [Many] books on sleep say that seven to eight hours is the norm, but at least 5% of the population sleep less than six hours. What’s key about sleep is that you have to get enough sleep for you. If you get however many hours you get and you’re not tired [the next day], then you’re getting enough sleep. It’s more about daytime function than hours of sleep. But then, those hours [that you do get] need to be of good quality. You might be sleeping seven or eight hours [a night], but if you wake up in the morning and you feel exhausted and tired during the [rest of the] day, there’s something wrong with your sleep.
MM: What are sleep disorders?
AB: There are 85–100 different sleep disorders, but there are generally three big groups. One is insomnia, which is not getting enough hours of sleep. Another one is hypersomnia, which means you’re getting the hours, but you’re feeling [overly] sleepy during the day. The third group is parasomnias, which are weird things that happen in the night, [for example] sleepwalking or sleep talking.
MM: Why did you start a sleep clinic at Ezintsha, which started as an HIV clinic?
Nomathemba Chandiwana (NC): Sleep disorders affect all populations, including people with HIV, and in one of our big trials we saw that people weren’t sleeping well. It’s a combination of things: it could be personal things to do with yourself [such as coping with stress or mental health issues], your ageing, other health conditions, such as obesity or diabetes, or the treatment that you’re on. HIV itself, for reasons we don’t quite understand, also affects your circadian rhythms [the natural cycles our bodies go through every 24 hours]. All these things, together with the environment that we’re in — worrying about our safety, loadshedding that wakes us up, and so on — affect our sleep.
MM: Do antiretroviral HIV medicines affect your sleep?
NC: Yes. Some of the medications can disrupt your sleep, causing you to not sleep enough or to sleep too much. For example, efavirenz, which we used before, affected people’s sleep, so we wouldn’t give that to, say, shift workers. The drug [regimen] we use now, called TLD [a combination of tenofovir, lamivudine and dolutegravir], not so much though, but it can cause some insomnia.
MM: Does having a condition such as diabetes, for example, influence your sleep patterns? And how does it work?
AB: Part of the reason why you get type 2 diabetes is often that you put on weight or have obesity. That will increase your risk of sleep apnoea. But as complications of diabetes, you can also get nerve damage in the legs, which can give you restless leg syndrome and periodic limb movements at night. The relationship between sleep and weight is interesting. If you don’t get enough sleep, studies show you’re more likely to be overweight. So, you don’t get enough sleep, then you [become] a bit overweight. Then if you get type 2 diabetes, you put on more weight. Eventually you could get sleep apnoea [which is when you stop breathing while asleep]. In patients who have type 2 diabetes, [more than] 60% are likely to have sleep apnoea.
MM: What causes sleep apnoea?
AB: Very simply, it’s [because of] a collapse of the airway at the back of the throat. The airway is designed to collapse every time you swallow, as the palate, epiglottis and the tongue closes off. But it shouldn’t collapse when you breathe [while asleep]. However, because of things like ageing, when the sides of the throat get floppier, or putting on weight, the [space in the] throat becomes narrower. So you start sucking harder through your nose to breathe in. It’s just a matter of time until the throat closes enough that the brain thinks you’re not breathing. It’s seen as very loud snoring, followed by a quiet patch. Then your brain makes you wake up, and air starts moving [through your throat] again.
MM: Why is sleep apnoea bad?
AB: Sleep apnoea causes two problems. Firstly, the oxygen [levels in your blood] start dropping if you’re not moving any air [into your lungs]. Secondly, during that sudden wake-up, your body gets a burst of adrenaline, which increases your heart rate and puts your metabolism on alert, like you’re ready to fight, instead of being in a rest phase. So you get woken up hundreds of times a night. [The result is that] you’re going to wake up tired and be tired during the day.
MM: How is sleep apnoea diagnosed?
NC: The gold standard [for diagnosis] is a polysomnogram, which is an overnight sleep study. It can also be a home sleep apnoea test, which is a screening test. Some apps on your phone or watch [can also] give rough information.
MM: How can sleep apnoea be treated?
NC: [The best way is with a] CPAP [continuous positive air pressure] machine, which helps to keep your throat open so that you’re getting enough air at night. However, that’s extremely expensive, especially in South Africa. Our ethos [at our clinic] is that sleep medicine should not be elitist medicine; 80% of our population wouldn’t have access to things such as a CPAP. Other less expensive ways of treating sleep apnoea could be positional therapy, like putting a spiky golf ball [on your back], so that if you sleep on your back, you’ll move. A mandibular device [a type of retainer you put in your mouth at night to help keep your airways open], some of which are available at your pharmacy or others from your dentist, for example, can also help.
MM: If you have a sleep disorder, can you be helped in the public sector?
AB: Not routinely. There are isolated sleep labs in South Africa that are based in the public sector, for example in neurology or pulmonology [departments]. But doctors that come out of medical school never really engage with sleep and sleep disorders, so they might not know patients have sleep problems, because they’re not asking those kinds of questions.
Part of what we’re going to be doing [at our sleep clinic at Wits] is research in those populations to find ways for treating sleep apnoea without needing a CPAP machine. Could we manage to bring patients from severe apnoea to mild apnoea, for example, which takes them out of that danger zone? [Our research will be] about training doctors, so that they learn more about sleep apnoea.
MM: Do teenagers and young people have sleep disorders too?
NC: They certainly do. Children and teenagers are not sleeping enough, especially with [after-school] activities, stress and technology. Going to sleep with [your] phones, iPads, TikTok and so on really interferes with sleep.
MM: What do you do if your teenager can’t sleep?
AB: One of the common sleep disorders that teenagers get is called delayed sleep phase syndrome, which is like a social jetlag. This means, timewise, the sleep phase gets shifted. For example, think of, say, a teenage boy during school holidays who stays up gaming till two o’clock and then sleeping till 11 in the morning. Then suddenly, school starts again, and they have to get up at six, but they’re stuck in this 2–11[am] time zone and they can’t pop back. So now they can only fall asleep at two in the morning, but they’re getting up at six. We use melatonin [a hormone produced by your brain to signal that it’s time for sleep] and a programme to kind of get them back in the right time zone, like you would if you travelled somewhere, so they’re able to sleep at the right time.
Linda Pretorius is Bhekisisa’s content editor. She has a PhD in biosystems from the University of Pretoria has been working as a science writer, editor and proofreader in the book industry and for academic journals over the past 15 years. At Bhekisisa she helps authors to shape and develop their stories to pack a punch.
