WASHINGTON – Insomnia is a disorder of hyperarousal rather than one of sleep deprivation, Thomas Roth, Ph.D., said at the annual meeting of the American Academy of Clinical Psychiatrists.
“Mothers of newborn babies don't have insomnia; they simply don't have adequate opportunities for sleep,” said Dr. Roth, director of research and chief of sleep medicine at the Henry Ford Hospital in Detroit.
Because 90% of people with insomnia have other comorbid conditions, insomnia was seen as a symptom rather than an independent disorder until 2005. That's when the National Institute of Mental Health declared that insomnia met the criteria for a disorder, which include impairment in function and quality of life that is associated with specific symptoms and rooted in physiology.
To meet the diagnostic criteria for insomnia, a person must report one or more of the following symptoms: difficulty falling asleep, difficulty staying asleep, or nonrestorative sleep.
When treating a patient who complains of chronic sleep problems, be sure to ask these several key questions, Dr. Roth said in an interview:
▸ What is the nature of the nighttime sleep problems (difficulty falling asleep, difficulty staying asleep)?
▸ What is the nature of daytime consequences (daytime sleepiness, impaired function)?
▸ What are the frequency and duration of symptoms?
▸ Does the patient have any comorbid medical or psychiatric conditions?
Prevalence data are limited, but about 30% of the general population has some type of disturbed sleep, Dr. Roth said.
Many patients with insomnia report that the daytime impairment and distress resulting from insomnia are more frustrating for them than their difficulty sleeping at night.
Chronic pain is a common comorbidity in insomnia patients. In addition, people with insomnia are significantly more likely to develop comorbid psychiatric disorders.
Dr. Roth cited a recent study from his laboratory in which the researchers evaluated 1,000 people who had never had a psychiatric disease and found that 240 met criteria for insomnia. At a follow-up 3.5 years later, the people with insomnia had 4.5 times the risk of developing a psychiatric disorder.
Treatment of insomnia remains a challenge, but recognition of the role of hyperarousal and the frequency of comorbidities allows for new therapeutic targets, including some sedating antidepressants.