INSOMNIA WATCH

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Study Examines State of Insomnia Therapy

A recent review article in Chest (July 2006) presented an interesting summary of the state of insomnia evaluation and treatment. Despite the high prevalence of insomnia and considerable progress made in its treatment, many clinicians still have difficulty properly addressing this disease.

In the United States, the annual cost attributed to insomnia is conservatively estimated at $92.5 billion to $107.5 billion, which makes the condition one of crucial public health importance. Key advances have recently been made in classifying, evaluating, and treating the disease. The value of some insomnia research, however, has not been completely realized, in part because of a lack of standardized insomnia definitions.

Improvements in patient assessment and outcome, as well as continued research efforts, also have likely been hampered. Fortunately, effective insomnia therapies exist. Intermediate-acting benzodiazepines are one commonly used option.

The authors conclude that, as the research and clinical guidelines for insomnia are fine-tuned and validated, physician understanding of the disorder will continue to grow, and patient success is likely to increase.

Data Show Temazepam Is Effective at High Altitude

Benzodiazepine agents safely and effectively induce sleep, but some patients may have concerns about the potential effects of this drug class. During a symposium of the Royal College of Physicians of Edinburgh (September 2005), researchers demonstrated the value of temazepam for inducing sleep at higher elevations, where sleep disruption is common and low levels of oxygen are a serious concern.

The efficacy and safety of temazepam 10 mg were assessed in a double-blind, crossover, randomized study involving a group that had undertaken a 17-day trek in the mountains of Nepal. These patients found the drug to be an effective and safe sleep agent. Oxygen saturation, for example, was not reduced in a clinically significant manner in the trekkers who used temazepam. Equally important, temazepam did not significantly impair nextday vigilance or reaction time, compared with the placebo.

The researchers noted the fact that acute mountain sickness afflicted temazepam-treated and untreated trekkers equally. The study confirmed the value of temazepam as an anti-insomnia agent that also may be used in nontraditional settings and patient groups.

Zopiclone Versus CBT

Research has suggested that both pharmacologic and psychological therapies have a place in treating insomnia. Yet, there have been few direct comparisons of these treatments. As reported in the Journal of the American Medical Association (June 2006), one widely used psychological intervention, cognitive behavioral therapy (CBT), appeared to have advantages over a nonbenzodiazepine medication.

In the study of adults aged >55 years, who were afflicted with chronic primary insomnia, the efficacy of zopiclone 7.5 mg was compared with that of CBT in a randomized, double-blind, placebo-controlled trial involving a 6-week treatment period. Overall, CBT resulted in improved short-and long-term outcomes in 3 of 4 sleep-efficacy assessments, versus zopiclone dosed once nightly. In fact, zopiclone did not differ from placebo in most measures of insomnia improvement.

CBT improved patients' sleep efficiency from approximately 81% pretreatment to 90% posttreatment, whereas the efficiency of zopiclone patients decreased slightly at follow-up. Those who underwent CBT spent more time in slow-wave sleep and less time awake than either the zopiclone or the placebo patients.

Research Evaluates Zolpidem Dependence

Despite a unique neurobiological mode of action that is different from classical insomnia agents, nonbenzodiazepines such as zolpidem have a potential risk for patient abuse and dependence, according to the authors of an article published in the March 2003 issue of the Journal of Psychopharmacology.

A number of reports of zolpidem dependence appear in the scientific literature, including 8 new cases that occurred in Greece. The authors reviewed cases of zolpidem abuse and dependence in patients who were prescribed the drug to treat insomnia. All of these zolpidem abusers reported craving the drug's anxiolytic and stimulant effects but not its sedative effects. The researchers noted that 7 of the patients also had no history of substance abuse—the primary factor that was previously thought to contribute to zolpidem dependence.

The authors hypothesized that zolpidem taken in high doses may result in a less selective activity at α1 subunit-containing γ-aminobutyric acid A type benzodiazepine receptors and thus produce adverse effects. They also discussed the clinical ramifications of this phenomenon and the possibility of a zolpidem abuse "syndrome" characterized by severe dependence, memory problems, and euphoria.