Insomnia prolongs depression in the elderly

By Karla Gale

NEW YORK (Reuters Health) - Persistent insomnia may perpetuate depression in elderly patients receiving standard care by primary care providers, according to study findings reported in the journal Sleep.

"This study highlights the importance of staying on top of insomnia that (occurs) with depression," lead author Dr. Wilfred R. Pigeon, from the University of Rochester Medical Center in New York, told Reuters Health. "We don't yet know which patients' insomnia will dissipate when depression starts to improve, so the most conservative approach would be to treat it when you see it."

Insomnia has historically been considered a symptom of depression, the authors note, and recent evidence suggests that insomnia is a risk factor for depression onset and recurrence. Whether insomnia represents a separate disorder remains open to question.

To explore these issues, the researchers examined data from Project IMPACT, a study conducted at 18 primary care clinics comparing enhanced care with usual care for late-life depression. The group consisted of 1,801 patients, age 60 or older, with a diagnosis of severe or mild depression.

"In the usual-care group, physicians were free to treat patients as they chose," Pigeon explained. "In the (enhanced care) group, patients received 'stepped care' by a nurse care manager, who provided...education about depression and brief 'problem-focused therapy'. Depending on their progress, the nurse could suggest medication changes to the primary care provider or suggest and facilitate a referral to a psychiatrist if there was still no progress."

Using standard diagnostic criteria, 293 subjects did not have insomnia, while 207 had persistent and 1,301 had intermediate insomnia.

Severe depression at 6 months remained in 44 percent of the patients with persistent insomnia, 29 percent of those with intermediate insomnia and 16 percent of those without insomnia.

In a subgroup analysis comparing patients without insomnia to those with persistent insomnia, persistence was associated with statistically significant greater risk of sustained depression at 6 and 12 months. The association was stronger in patients diagnosed with severe depression and among those receiving usual care.