Lack of sleep linked to mental illness

Amy Corderoy – Sydney Morning Herald, September 1, 2010

Young people who get very little sleep are much more likely to become mentally ill, Australian research shows. Lack of sleep might help explain the puzzling increase in mental illness among young people over the past decades, said the research leader, Nicholas Glozier.

He suggested late-night internet use might be one reason young people were sleeping less. The study of about 20,000 people aged between 17 and 24 found those who slept less than five hours a night were three times more likely than normal sleepers to become psychologically distressed in the next year. Each hour of sleep lost was linked to a 14 per cent increased risk of distress.

“Sleep disturbance and in particular insomnia is a predictor of later development of depression and possibly anxiety,” said Professor Glozier. Less sleep was also associated with longer-term mental health problems. “A lot of mental ill-health comes and goes,” he said. “It’s the ones that don’t get better that we are particularly interested in.” Professor Glozier, who researches in psychiatry and sleep medicine at the University of Sydney, believed lack of sleep could contribute to increasing rates of depression.

“Older people and people in middle age have been sleeping longer but young people have not,” he said. “Large numbers of my patients are on Facebook or the internet or massive multiplayer games until one or two in the morning but are having to get up at 7am.” Sleep problems and mental illness could exacerbate each other.

“Many of these kids could have sleep problems as a result of previous disturbances,” he said. “But what we are seeing [are] young adults who tend to start off with anxiety and body clock problems [and] move on to problems like bipolar or major depression.” Along with researchers from the Woolcock Institute and the Brain and Mind Research Institute, Professor Glozier is pioneering methods to change the body clocks of sleep-deprived people. “Their body clocks are naturally out of kilter with the rest of society and [some] of them this really impacts on,” he said. Patients are treated with light therapy in the mornings as well as hormones such as melatonin to help them sleep earlier, which may help their distress. The study used data collected by the George Institute for Global Health, and was published today in the journal Sleep.