Sleep strategy can ease depression

Millions of people stare at the ceiling each night as they struggle to sleep. Their favorite activities no longer bring them joy. Minor setbacks spark outbursts of anger or extended periods of sadness.

They’re common symptoms of depression, a condition that affects about 16 percent of Americans. Researchers worldwide have tested whether sleep-focused strategies can have a positive impact on depression.

One paradoxical finding has been that drastic sleep deprivation can immediately improve depression symptoms. But symptoms usually return when sleep is allowed the next day. And keeping people awake all night can have dangerous consequences the next day.

So J. Todd Arnedt, director of the University of Michigan Sleep and Circadian Research Laboratory, took a different approach. He evaluated whether a more modest form of sleep deprivation would spur benefits similar to drastic sleep deprivation but without the side effects.

The University of Michigan recruited about 70 adults diagnosed with depression and provided each with an antidepressant medication for eight weeks. Half the participants were asked to spend eight hours in bed each night for the first two weeks, while the other half had to spend six hours in bed nightly — a modest cutback compared to previous studies that asked participants to stay up all night, but still less sleep than most people need on a nightly basis.

“A number of previous studies have looked at extreme forms of sleep deprivation for depression, but I wanted to see whether sleep duration during the early stages of treatment had any sort of impact on how people respond to antidepressant medication,” said Arnedt. “What we found is that the amount of sleep obtained during depression treatment matters and critically affects people’s response to their depression medication.”

Contrary to what total sleep deprivation studies in depression have found, his study revealed that participants who were in bed for eight hours each night — an adequate nightly sleep duration — during the first two weeks of antidepressant treatment had greater mood improvements than those who stayed in bed for only six hours nightly. And by the end of eight weeks of treatment, 75 percent of the participants who were in bed for eight hours also experienced remission from their depression symptoms. Depression remission also occurred on average one week earlier for depressed individuals in the eight-hour sleep group.

“It’s well known that it takes an extended period of time before antidepressant medication takes effect — anywhere from six to eight weeks,” Arnedt said. “Anything we can do to reduce that period would be a huge benefit to millions of people who suffer from this debilitating mental illness.”