Curing insomnia in people with depression could double their chance of a full recovery, scientists are reporting. The findings, based on an insomnia treatment that uses talk therapy rather than drugs, are the first to emerge from a series of closely watched studies of sleep and depression to be released in the coming year.
A student demonstrating equipment at Colleen Carney’s sleep lab at Ryerson University. Dr. Carney is the lead author of a new report about the effects of insomnia treatment on depression.
The new report affirms the results of a smaller pilot study, giving scientists confidence that the effects of the insomnia treatment are real. If the figures continue to hold up, the advance will be the most significant in the treatment of depression since the introduction of Prozac in 1987.
Depression is the most common mental disorder, affecting some 18 million Americans in any given year, according to government figures, and more than half of them also have insomnia.
Experts familiar with the new report said that the results were plausible and that if supported by other studies, they should lead to major changes in treatment.
“It would be an absolute boon to the field,” said Dr. Nada L. Stotland, professor of psychiatry at Rush Medical College in Chicago, who was not connected with the latest research.
“It makes good common sense clinically,” she continued. “If you have a depression, you’re often awake all night, it’s extremely lonely, it’s dark, you’re aware every moment that the world around you is sleeping, every concern you have is magnified.”
The study is the first of four on sleep and depression nearing completion, all financed by the National Institute of Mental Health. They are evaluating a type of talk therapy for insomnia that is cheap, relatively brief and usually effective, but not currently a part of standard treatment.
The new report, from a team at Ryerson University in Toronto, found that 87 percent of patients who resolved their insomnia in four biweekly talk therapy sessions also saw their depression symptoms dissolve after eight weeks of treatment, either with an antidepressant drug or a placebo pill — almost twice the rate of those who could not shake their insomnia. Those numbers are in line with a previous pilot study of insomnia treatment at Stanford.
In an interview, the report’s lead author, Colleen E. Carney, said, “The way this story is unfolding, I think we need to start augmenting standard depression treatment with therapy focused on insomnia.”
Dr. Carney acknowledged that the study was small — just 66 patients — and said a clearer picture should emerge as the other teams of scientists released their results. Those studies are being done at Stanford, Duke and the University of Pittsburgh and include about 70 subjects each. Dr. Carney will present her data on Saturday at a convention of the Association for Behavioral and Cognitive Therapies, in Nashville.
Doctors have known for years that sleep problems are intertwined with mood disorders. But only recently have they begun to investigate the effects of treating both at the same time. Antidepressant drugs like Prozac help many people, as does talk therapy, but in rigorous studies the treatments, administered individually, only slightly outperform placebo pills. Used together the treatments produce a cure rate — full recovery — for about 40 percent of patients.
Adding insomnia therapy, however, to an antidepressant would sharply lift the cure rate, Dr. Carney’s data suggests, as do the findings from the Stanford pilot study, which included 30 people.
Doctors have long considered poor sleep to be a symptom of depression that would clear up with treatments, said Rachel Manber, a professor in the psychiatry and behavioral sciences department at Stanford, whose 2008 pilot trial of insomnia therapy provided the rationale for larger studies. “But we now know that’s not the case,” she said. “The relationship is bidirectional — that insomnia can precede the depression.”
Full-blown insomnia is more serious than the sleep problems most people occasionally have. To qualify for a diagnosis, people must have endured at least a month of chronic sleep loss that has caused problems at work, at home or in important relationships. Several studies now suggest that developing insomnia doubles a person’s risk of later becoming depressed — the sleep problem preceding the mood disorder, rather than the other way around.
The therapy that Dr. Manber, Dr. Carney and the other researchers are using is called cognitive behavior therapy for insomnia, or CBT-I for short. The therapist teaches people to establish a regular wake-up time and stick to it; get out of bed during waking periods; avoid eating, reading, watching TV or similar activities in bed; and eliminate daytime napping.
The aim is to reserve time in bed for only sleeping and — at least as important — to “curb this idea that sleeping requires effort, that it’s something you have to fix,” Dr. Carney said. “That’s when people get in trouble, when they begin to think they have to do something to get to sleep.”
This kind of therapy is distinct from what is commonly known as sleep hygiene: exercising regularly, but not too close to bedtime, and avoiding coffee and too much alcohol in the evening. These healthful habits do not amount to an effective treatment for insomnia.
In her 2008 pilot study testing CBT-I in people with depression, Dr. Manber of Stanford used sleep hygiene as part of her control treatment. She found that 60 percent of patients who received seven sessions of the talk therapy and an antidepressant fully recovered from their depression, compared with 33 percent who got the same drug and the sleep hygiene therapy.
In the four larger trials expected to be published in 2014, researchers had participants keep sleep journals to track the effect of the CBT-I therapy, writing down what time they went to bed every night, what time they tried to fall asleep, how long it took, how many awakenings they had and what time they woke up.
When the diaries show consistent, seldom-interrupted, good-quality slumber, the therapist conducts an interview to determine if there are any lingering issues. If there are none, the person has recovered. The therapy results in sharp reductions in nighttime wakefulness for most people who follow through.
In interviews, several researchers noted that the National Institute of Mental Health had sharply curtailed funding for work in sleep treatment. Aleksandra Vicentic, the acting chief of the agency’s behavioral and integrative neuroscience research branch, said that in 2009 the funding strategy changed for sleep projects.
In an effort to illuminate the biology of sleep’s impact on behavior, the agency is now focusing on how sleep affects the functioning of neural circuits. But Dr. Vicentic added that the agency continued to fund clinical work like the depression trials.
Dr. Andrew Krystal, who is running the CBT-I study at Duke, called sleep “this huge, still unexplored frontier of psychiatry.”
“The body has complex circadian cycles, and mostly in psychiatry we’ve ignored them,” he said. “Our treatments are driven by convenience. We treat during the day and make little effort to find out what’s happening at night.