As work continues on the newest edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM), still three years away, one of the sections that might see the greatest overhaul relates to sleep disorders.
Around 10 disorder names are expected to be added to the category, while just as many might be removed or subsumed under other categories. Most of the traditional sleep disorders will be classified in the primary groups’ insomnia, hypersomnia, and arousal disorder, with “specifiers” that give more detail but don’t suggest a possible cause, as the current manual does.
The sleep disorders work group believes the causal language serves no practical function. In the next DSM, then, “insomnia related to another mental disorder” will be classified under insomnia, with the specifier that it’s a co morbidity, while the current “hypersomnia related to another mental disorder” will be categorized under hypersomnia, also with the “co morbidity” specifier.
Sleep psychologists welcome the change, saying it reflects today’s more sophisticated understanding of sleep disorders.
“The traditional wisdom was that insomnia is a symptom,” says Donn Posner, Ph.D., director of the Behavioral Sleep Medicine Program for the Sleep Disorders Center of Lifespan Hospitals, who works primarily with insomnia. “If you look beneath depression, you’ll see sleeplessness, insomnia…Yet in the past 10 years, a plethora of studies of insomnia in the context of depression, sleep apnea, cancer, pain, etc., have shown that treating insomnia works for alleviating symptoms of these other conditions as well. Traditional wisdom would have been you couldn’t have had success without treating the so-called primary condition first.”
Posner adds that even in cases in which insomnia grew out of depression, insomnia “tends to have behavioral factors that keep it alive.
“Once a person gets in a pattern and begins worrying about not sleeping, the sleep problem can evolve a life of its own,” he says.
In addition to its relation to psychological distress, insomnia is now also recognized as a risk factor for medical conditions including hypertension and obesity.
Shelby Freedman Harris, Psy.D., director of the Behavioral Sleep Medicine Program at Montefiore Medical Center’s Sleep-Wake Disorders Center in Bronx, N.Y., agrees that the changes are largely positive. She says the added detail will bring the DSM more closely in line with the International Classification of Sleep Disorders, which is used widely by sleep researchers and clinicians.
Harris echoes some of Posner’s observations about insomnia, and notes the benefit of highlighting circadian rhythm disorder, which is expected to be listed among the primary sleep disorders in the DSM-5.
“If someone’s going to bed at six or seven at night, [under the new classification], you won’t just assume it’s depression,” she says. “It might be a separate disorder.”
Among the other disorders that might be added in the new DSM are Kleine-Levin syndrome (stretches of excessive sleep), restless legs syndrome, and rapid eye movement disorder. The current “breathing-related sleep disorder” will likely be broken down into three different disorders (“primary alveolar hypoventilation” and two forms of sleep apnea). Though not regarded as mental illnesses, those sleep disturbances might lead people to seek treatment from mental health professionals. Narcolepsy and nightmare disorder will be relatively unchanged.
Harris says one area the new DSM is lacking is attention to sleep disorders in children. Identifying disorders and prescribing medication for children is often difficult; without a well-defined diagnosis, it might be a challenge to get insurance to pay for treatment, she says.
Yet, overall, the new DSM, like those before it, should facilitate diagnosis and treatment, Posner says.
“As the DSM evolves, the criteria are laid out a little bit better,” he says. “But it’s always evolving.”
By Ami Albernaz