More and more of us are suffering from sleep deprivation. It could lead to impaired cognitive function, writes Helen O’Callaghan.
FOR two months I only slept three or four hours a night. That was 10 years ago and I’d just landed a job I had really wanted. A week of sleepless nights because of new-job-nerves might have been understandable, even normal, but this morphed into insomnia.
I tried everything — lavender on the pillow, relaxation tapes, caffeine reduction, and I shunned TV and stimulating mental activities in the run-up to bed-time. Nothing worked — most nights, I saw the clock strike 2am, 3am, 4am. I was caught in an endless loop of worrying that I couldn’t sleep — and then not being able to sleep.
It resolved eventually: a short course of sleeping tablets and — somehow — deciding not to worry about it anymore, telling myself ‘it’s ok if I don’t sleep, I used to sleep well, I will again’. And I did. Now, if I have trouble nodding off or if I wake up three times in a night, I simply refuse to worry about it.
Sleep is essential to our health. It’s is also core to our cognitive functioning. A recent US study found chronic sleep loss may irreversibly damage brain cells. Professor Sigrid Veasey, and his colleagues at the Center for Sleep and Circadian Neurobiology, at the University of Pennsylvania, said extended wakefulness in mice caused injury to — and loss of — neurons essential for alertness and optimal cognition.
“We’d predict [with chronic sleep loss] these same neurons would be injured and lost in humans. After the study came out, I heard of many shift-workers who felt they weren’t as sharp as they’d been before they started doing shifts — generally, shift-workers report getting about five-and-a-half hours of sleep in the 24-hour period,” Veasey said.
While some people are alert and functioning after just six hours of sleep, Veasey says such cases are rare. “The vast majority think they’re fully functioning, but, in reality, they’re grossly impaired — there’s loss of accurate perception of the impairment. They can’t fully attend to what’s going on — during a lecture, they’ll likely zone-out five or six times more frequently than if they’d had sharp sleep.”
Veasey says scientists are increasingly debunking the theory that you can catch up on lost sleep at weekends. In studies, people who get five hours’ sleep nightly, Monday to Thursday, followed by a three-day weekend of nine hours per night, still have impaired attention and slower reaction times.
“The connection between neurons is lost. These have to regrow and they don’t regrow over a weekend. It’s astounding what the recovery period is — six months later, people are pretty much back to baseline, but this is in healthy young adults who eat and exercise well. As we age, and the brain’s hit with more insults, healing can take longer.”
In Ireland, 10 to 15% of us suffer from insomnia — difficulty getting to sleep, trouble staying asleep, early-morning awakening or restless sleep. It can be transient (adjustment insomnia), lasting less than a week; short-term, lasting one to three weeks; or chronic, lasting for more than a month, which occurs at least three nights weekly and accounts for 80% of insomnia patients. A diagnosis must include day-time impairment — fatigue, impaired concentration/short-term memory, mood disturbance, sleepiness, reduced energy, increased error and proneness to accident.
Insomnia is increasing, according to figures from the Primary Care Reimbursement Service. Prescriptions filled for Zopiclone and Zolpidem, the two most common sleeping tablets dispensed here in 2013, under the GMS scheme, numbered 1,135,798.
In 2010, the equivalent number was 796,527. The figures don’t include sleeping tablets taken by people outside these schemes. Sleep physiologist, Breege Leddy, says only two to five percent of people with insomnia use prescription medicine, but many sufferers are poaching sleeping tablets off friends and relatives, or buying them online.
“There’s a place for sleep medication, but only in the short-term, up to two or three weeks at a time, and only at the lowest effective dose,” she says. Side-effects of sleeping tablets include impaired cognitive ability and memory, greater accident proneness, as well as a risk of falling for older people, adverse interaction with other meds and rebound insomnia when trying to come off them.
“Some sleeping tablets change the normal architecture of sleep — our sleep is a very organised process. There’s no substitute for a natural night’s sleep — sleep from hypnotics isn’t as restorative,” says Leddy.
Patrick Fuller, assistant professor of neurology in the division of sleep medicine at Harvard Medical School, says the best thing about sleep meds is that they can put people to sleep. But it’s unfortunate, he says, that the vast majority of them have highly undesirable side-effects, because they don’t specifically target sleep or wake circuits in the brain, but rather circuits controlling all kinds of other behaviours and systems.
“There are extreme examples of people engaging, without conscious awareness, in a variety of behaviours while on these drugs — consuming non-edible items, having sex, attempting to drive cars. Others experience milder, unpleasant side-effects, with many likening the post-sleep period to a hangover.”
Fuller was senior author in a recent study that demonstrated for the first time that a small region within the brainstem is the key to deep sleep.
When this parafacial zone was activated by investigators, animals fell into a deep sleep, no matter the time of day and without any sedating drugs. Fuller says the research means we can anticipate development of “newer, safer and more targeted sleep-promoting drugs” in the next decade or so.
Do people underestimate the part stress plays in insomnia? Fuller says yes. “Stress is potently wake-promoting. Many investigators in the sleep field feel stress can override some of the sleep circuitry and result in insomnia.”
Andrew Coogan, senior lecturer in department of psychology at NUI, Maynooth, says insomnia is a software problem rather than a hardware one — it’s “primarily driven by psychological factors, rather than being a result of ‘hardwired’ features of the brain hardware”. He talks about the three Ps of insomnia — factors that are predisposing, precipitating and perpetuating.
Predisposing factors may increase insomnia risk — previous history, family history, various chronic diseases. Insomnia rates can jump to 75% in people with depression.
Precipitating factors beg the question: ‘Why is it I didn’t have insomnia before, but I do now?’ First up are environmental issues — like Goldilocks, says Coogan, it matters how warm and dark is our bedroom, how hard our mattress. Then, there’s lifestyle change — from moving time zones and starting night-shifts to changing jobs or getting pregnant. Whether good or bad, change causes stress, and is disruptive to natural sleep rhythms.
“Anything that upsets you or your body’s physiology can upset your sleep,” says Coogan
With core body temperature dipping prior to, and during, sleep, women are at a natural disadvantage — reproductive-related transitions (pregnancy, menopause or menstrual-cycle changes) raise core temperature.
“In a regular menstrual cycle, there’s a four- or five-degree rise in body temperature in the second-half of the cycle — around period time, women might have a few nights of disturbed sleep,” says Dr Shirley McQuade, director of Dublin Well Woman Centre. It’s a similar story in pregnancy — increased hormones make women feel warmer, so they don’t get into deep sleep, and in menopause, when night sweats prevent or interrupt sleep.
While for some people sleeplessness is a passing phase, others develop a chronic, ongoing problem.
Dr Coogan sees perpetuating factors at work here — such as dysfunctional attitudes about sleep. “People panic — ‘oh my God, if I don’t get eight hours’ sleep, I’ll be wrecked tomorrow’.”
At the Bon Secours Hospital insomnia clinic in Glasnevin, Breege Leedy has a special interest in cognitive behavioural therapy (CBT). She says all recent studies show it’s the most effective form of non-pharmacological treatment for insomnia. The clinic is inundated — by the time patients get here, they’ve tried everything. “CBT promises lasting effects, giving patients tools to manage insomnia. Eighty-five international studies find 70 to 80% of patients show lasting improvement. I see more than 80% improvement.”
Having monitored the patient for a week pre-programme (to determine their sleep schedule), CBT emphasises sleep hygiene — pre-bedtime wind-down routine; shutting down all smart devices and work activities; consuming no more than two caffeinated drinks a day; dark, quiet and cool bedroom. Stimulus-control therapy tackles negative associations people with insomnia develop about their bed — they dread it as a place where they toss and turn.
“We encourage sleep restriction — getting out of bed after 15 minutes if you can’t sleep,” says Leddy, who teaches techniques to calm busy minds consumed with “planning, rehearsing thoughts, or random thoughts that keep you darting from idea to idea”.
CBT challenges misperceptions and wrong expectations of sleep, putting more comforting thoughts in their place.
“People who can’t sleep think ‘how will I cope with work tomorrow’?” says Leddy. She tells them the body’s designed to cope with some sleep deprivation — also, most people get more sleep than they think each night.
From my own brush with insomnia, I discovered curing it was about getting back my sleep confidence, focusing on what was good about my personal sleep.In my case, while I struggled to enter the land of Nod, once there I was generally good at staying. Plus, I’d always previously had a good sleep rhythm — I assured myself this would return.
Sleep’s a natural process. You can’t force it. And you don’t need to.
Very often, it’s a matter of calming your hyper-chattering mind — the body knows perfectly well how to fall asleep.
Awake all night? Sleep on it...
Falling asleep is about letting go, says Derval Dunford, of Mindfulness Matters. She suggests the following techniques:
* Body scan — focus attention on different parts of the body, starting with the feet and working your way up to the crown of the head. Notice the contacts each part of your body is making with the bed. Breathe in and out of each area — on the outbreath, soften the area. Gently bring the wandering mind back to the body.
* Abdominal breathing is deeper, more relaxed, and into the lower part of the lungs. Focus on the abdomen. Feel gentle, rhythmic rise and fall as you breathe in and out. On the inbreath, count to seven; on the outbreath, count to 11 — naturally extending the out-breath is relaxing.
* Natural remedies Herbalist Megan Sheppard says sedative herbs calm nerves and relieve tension. Research any contraindications, if taking medication.
* Hops calm busy brains — good if your mind has trouble switching-off.
* Lavender - for when sleep loss is due to tension and stress. This is soothing and can help with headaches, digestion and depression. It can be over-stimulating for some — very weak brew is more effective.
* Chamomile is effective, but some people don’t tolerate it — for them, it can cause irritability, nausea and skin irritations.
* Passionflower and valerian are more like mild herbal tranquilisers (non-addictive). Passion flower helps disturbed sleeping patterns and short-term insomnia. Valerian is useful for overactive minds and relaxes overly-contracted muscles (effective for insomnia associated with injury/long-term pain).
* Linden is gentle, and effective when emotional stress is a factor — often used for people who struggle with anxiety, panic attacks and who worry about everything.
* Some stimulant herbs also help with insomnia — particularly when you’re too exhausted to sleep. Oats and ginseng (usually Panax or Siberian) are the top two — take oats at any time; ginseng should only be taken during the day. Ginseng shouldn’t be used in under-12s or by pregnant/breastfeeding women. Avoid taking caffeine alongside ginseng.
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