Diagnosis and treatment of insomnia

The diagnostic criteria and treatment of insomnia are reviewed.

Insomnia is most often described as a subjective complaint of poor sleep quality or quantity despite adequate time for sleep, resulting in daytime fatigue, irritability, and decreased concentration. Insomnia is classified as idiopathic or comorbid. Comorbid insomnias are associated with psychiatric disorders, medical disorders, substance abuse, and specific sleep disorders. Idiopathic insomnia is essentially a diagnosis of exclusion. A wide array of terminology exists for defining the duration of insomnia symptoms, which may add to the confusion regarding insomnia classification. Acute insomnia refers to sleep problems lasting from one night to a few weeks, whereas chronic insomnia refers to sleep problems lasting at least three nights weekly for at least one month. Diagnostic tools for identifying insomnia are multifactorial. Nonpharmacologic interventions for insomnia include sleep-hygiene education, stimulus-control therapy, relaxation therapy, and sleep-restriction therapy. The most effective pharmacologic therapies for insomnia are benzodiazepines, benzodiazepine-receptor agonists, melatonin-receptor agonists, and antidepressants. Choice of a specific agent should be based on patient-specific factors, including age, proposed length of treatment, primary sleep complaint, history of drug or alcohol abuse, and cost.

Many treatment options are available for patients with insomnia. Behavioral therapies should be initiated as first-line treatment in most patients. For patients who require the addition of pharmacologic therapy, the drugs with the most evidence for benefit include benzodiazepines, benzodiazepine-receptor agonists, melatonin-receptor agonists, and antidepressants. Selection of a specific agent must take into account numerous patient-specific factors.