Studies Link Insomnia to Depression in Young and Old

Two studies appearing in this month's edition of the journal SLEEP provide new insight into the relationship between insomnia and depression.

The first study followed 591 young adults for 20 years. Results showed that the prevalence and severity of insomnia increased with age. Episodes of insomnia lasting two weeks or longer had a high chance of predicting an episode of major depression, revealing the sleep disorder as not just a symptom, but a cause of depression.

The second study focused on depression and dysthymia patients age 60 or older who experienced persistent, intermediate or no insomnia. Subjects were assessed for depression and insomnia at six and 12 month intervals. In this case, insomnia was found to perpetuate depression: Patients with insomnia were 1.8 to 3.5 times more likely to remain depressed than subjects without.

About 30 percent of adults suffer from symptoms of insomnia, potentially putting themselves at risk for depression as well as obesity, diabetes and attention and memory problems.

The American Academy of Sleep Medicine (AASM) recommends avoiding insomnia by maintaining a consistent sleep schedule, avoiding exercise, big meals and stimulants such as caffeine before sleeping and establishing a relaxing setting at bedtime.

ABSTRACT: Prevalence, Course, and Comorbidity of Insomnia and Depression in Young Adults

ABSTRACT: Is Insomnia a Perpetuating Factor for Late-Life Depression in the IMPACT Cohort?