Insomnia blunts antidepressant response in elderly: chronic insomnia linked to increased risk of continued depression after 12 months of antidepressant use.(Clinical Rounds)

DENVER -- Chronic insomnia in depressed elderly patients confers roughly a ninefold increased risk of continued depression after as much as 12 months of antidepressant therapy, Wilfred Pigeon, Ph.D., reported during the annual meeting of the Associated Professional Sleep Societies.

"These findings suggest that chronic insomnia blunts treatment response in patients in this intervention study. This means, therefore, that chronic insomnia is not only a precipitating factor, as has been shown by a dozen or so studies, but that it now can also be considered a perpetuating factor, at least in this elderly sample. As such, it represents a modifiable risk factor for new-onset, recurrent, and, now, ongoing depression," said Dr. Pigeon, assistant director of the sleep laboratory at the University of Rochester (N.Y.).

He reported on 1,221 patients aged 65 years or older with major depressive disorder--60% of them women--who participated in Project IMPACT (Improving Mood Promoting Access to Cognitive Treatment).

Participants in this primary care practice-based trial were randomized to either usual care or a stepped-care intervention involving antidepressant medication and/or counseling delivered by their primary care physician, who worked in collaboration with a Project IMPACT case manager. A total of 1,801 elderly depressed patients enrolled in the study; however, those with dysthymia only were excluded from this analysis.

Overall, 206 patients had persistent insomnia both at baseline and after 6 months, whereas 644 had transient insomnia--meaning that they had insomnia as defined by their score on the three sleep-related items on the symptom checklist (SCL) at one of these time points. The remainder did not have insomnia at either time point.

Remission of major depression was defined as a score lower than 0.5 on the 17 relevant items of the SCL, exclusive of the three items used to assess for insomnia. By this criterion, 38% of the no-insomnia group had achieved remission at the 6-month mark, compared with ...