A peaceful night's sleep is not an easy achievement for the small percentage of adults who suffer from parasomnias, but it can be treated, writes Hélène Hofman
Sleepwalking is common among children, but a family history, anxiety and sleep deprivation can cause the condition to carry on into adulthood. Up to 40 per cent of children will sleepwalk at least once by the age of 12, with 6-7 per cent sleepwalking more than once a year. With adults, this is reduced to 0.5-3 per cent.
"Sleepwalking is one of the parasomnias," explains Dr Catherine Crowe, a sleep disorders consultant.
"Parasomnias are undesirable behaviours that occur during sleep, like sleep talking, night terrors or bed wetting.
"Sleepwalking can involve simple behaviour such as just getting up or going to the toilet, but it can also be more complex and consist of symbolic gestures. For example, there was a mother whose kids had left the house, getting up and setting the table, or another man would pack a suitcase. But for most people it is just ordinary stuff," she says.
According to Crowe, who is based in the Mater Private Hospital's Sleep Laboratory in Dublin, an adult has about four sleep cycles a night and sleepwalking occurs at the end of the first or second cycle - the deepest parts of sleep.
The average episode lasts between one and five minutes, during which time the person will have their eyes open and may appear to be awake but will not respond to communication.
Anyone with a close relative who sleepwalks is 10 times more likely to do so themselves, but sleep deprivation and anxiety can also contribute.
"If you're out late one night, you will have catch-up deep sleep the following night, which means you're more likely to sleep walk," says Crowe.
"This can also happen the night after a long-haul flight and it's something you should be aware of on holidays if you do sleepwalk. At home you might go out of the bedroom and to the left into your bathroom, but on the seventh floor of your apartment building in Spain that may be the way to the balcony."
Last month, a 56-year-old Scottish woman fell out of a hotel window in Essex. She had been sleepwalking when she climbed out of the window and fell 20ft to the ground, fracturing her arms and legs.
Similarly, in November 2004 Helen Moran (37), originally from Ballina, Co Mayo, fell 30ft from her apartment window in Glasgow while sleepwalking. She suffered two blood clots to her brain, a broken pelvis and ribs and a burst spleen.
Last September, Michael Catting (28) from London failed to get his 13-year jail sentence for stabbing his girlfriend to death reduced.
He used the defence of automatism, claiming he had been sleepwalking when he did it and had no recollection of the incident.
"There are cases where people get injured, but when you hear of people who drive cranes or cars in their sleep, I wonder is there a psychiatric aspect. Sleepwalking is a calm, mooching behaviour," says Crowe.
"It's quite short and confined to sleep cycles, which are only about an hour long. So the more bizarre the story, the less likely it is to be sleepwalking. Many of these stories just don't fit the physiology of sleep," she says.
However, Crowe acknowledges that more violent episodes can be attributed to night terrors, which affect less than 1 per cent of adults.
"With night the person is aware of a terrible danger, but they don't always know what and they will try to escape that danger. This can evolve into sleepwalking but usually the person won't get out of bed. They will just sit up and screech in terror and that lasts a couple of minutes. In these cases there's usually an underlying psychological problem," she says.
"Sleepwalking is generally something that can be readily addressed," says Dr Brian Lynch, a paediatric neurologist at Temple Street Children's Hospital in Dublin.
"It's common with children and in most cases it isn't a problem. But we do get the odd kid who is up every night and at risk of walking out onto the street or simply disrupting the rest of the family. There was one kid who would get up and vacuum the house in his sleep.
"Although there is no cure, it is something that can be controlled. In very rare and extreme cases, you can prescribe medication to try to knock out their sleep pattern, which may stop the sleepwalking. But parasomnias often happen when people aren't getting enough sleep - they're sleep- deprived, or stress is leading to sleep deprivation, and so with kids we would look at the level of sleep they're getting first," he says.
With adults, improving the quality of their sleep, by cutting down on caffeine or alcohol and reducing stress, can help. Where the cause is more complicated, a sleep clinic can assess the problem and work on controlling it. Another increasingly popular option is hypnotherapy.
"Hypnosis is probably the most successful way of tackling sleepwalking," says Dr Joseph Keaney, a Cork-based clinical hypnotherapist.
"Sleepwalking happens during REM or deep sleep, and with hypnosis you get back to that level. Generally people come for help when the partners get fed up and say, 'okay, that's it, let's do something about this'.
"You can have cases where people are screaming and shouting and trying to get out of the room or out of the window, and their partner has had enough," says Keaney.
According to Keaney, many parasomnias are related to past traumas and hypnotherapy can help determine the exact cause by putting the person in a trance and returning to that time. For example, one patient had a male relative who was in hospital and she would get up in the middle of the night because she felt she had to be near him.
In most cases the problem is cured in eight to 10 sessions, he says.
"The frequency of sleepwalking can sometimes increase if the person is stressed and this is another thing that can be addressed through hypnosis," says Keaney.
"We can also work on providing unconscious cues to prevent sleepwalking. These can come into play when they sit up in bed or if their feet touch the ground and help them get back to enjoying a good night's sleep," he says.