Can’t sleep? Feeling depressed?

You’re not alone. Both insomnia and depression are surprisingly common complaints. About 15% of adults suffer from chronic insomnia. Nearly as many suffer occasional bouts of depression.

Insomnia and depression often go hand-in-hand. Although just 15% of people with depression sleep too much, as many as 80% have trouble falling asleep or staying asleep. Patients with persistent insomnia are more than three times more likely to develop depression.

The relationship between insomnia and depression is far from simple, however. “Until recently, insomnia was typically seen as a symptom of depression,” says Michael L. Perlis, MD, an associate professor of psychiatry and director of the Behavioral Sleep Medicine Program at the University of Pennsylvania. “Treat the underlying depression, the thinking went, and sleep problems would go away.”

But new research shows that insomnia is not just a symptom of depression. “What we’ve come to understand is that insomnia and depression are two distinct but overlapping disorders,” says Perlis. Research shows that by treating both simultaneously, doctors have a better shot at improving a patient’s sleep quality, mood, and overall quality of life.

Can Insomnia Trigger Depression?

It’s easy to understand how insomnia might be linked to depression. “Chronic sleep loss can lead to a loss of pleasure in life, one of the hallmarks of depression,” explains Stanford University research psychologist Tracy Kuo, PhD. “When people can’t sleep, they often become anxious about not sleeping. Anxiety increases the potential for becoming depressed.”

Indeed, recent findings show that insomnia often shows up before a bout of depression strikes, serving as a useful warning sign. A worsening of insomnia can also signal depression.

But the relationship is far more than simply cause and effect. When depressed people suffer from insomnia, their risk of recurring depression is greater than that of patients who don’t have insomnia. “So insomnia may serve as a trigger for depression,” Perlis says. “But it also appears to perpetuate depression.”

How Insomnia Treatment Can Ease Depression

The latest findings have helped improve treatment strategies. Evidence shows that treating sleep problems can ease depressive symptoms and may even prevent relapses. In one study, 56 people who suffered both depression and insomnia received psychotherapy for their sleep problems alone. The symptoms of depression eased in more than half of the people, even though their treatment had not targeted depression.

Another study, with 545 patients, found that depressed patients with insomnia who were treated with both an antidepressant and a sleep medication fared better than those treated only with antidepressants. The people treated for both insomnia and depression slept better and their depression scores improved significantly more than patients on antidepressants alone.

“Both of these studies offer strong evidence for why it’s so important to treat insomnia, whether it’s associated with depression, chronic pain, cancer, or other co-existing disorders,” Perlis tells WebMD.

Medication or Therapy to Treat Insomnia

Insomnia can be treated in two very different ways: with medication or with cognitive behavioral therapies. In studies, medications have been shown to shorten the time it takes for people with insomnia to fall asleep. They can also help people stay asleep.

Cognitive behavioral therapy for insomnia, or CBT-I, has also been shown to be effective. This therapy is aimed at encouraging healthier behaviors and more positive and realistic thought processes around sleep. It encourages better sleep habits such as going to bed at the same time at night and eliminating distractions from the bedroom. CBT-I also helps people replace negative thoughts (“I’ll never fall asleep”) with positive alternatives (“It’s normal to take a little while to fall asleep“).

Which Insomnia Treatment Works Best for Depression?

Which approach — medication or therapy — works best? Each has its plusses and minuses. Studies have shown that insomnia medication can help jump-start better sleep by taking effect quickly. So it is often prescribed for people who have become very anxious about not sleeping. “But we also know that when people go off sleep medications, their sleep problems often recur,” Perlis says.

Sleep-related cognitive behavioral therapy, in contrast, takes more time to begin working. (A standard course of therapy typically takes about 8 to 12 weeks). But research shows that the benefits of CBT-I are more durable and longer lasting.

“That makes sense,” says Kuo. “With cognitive behavioral therapy, you’re learning a skill set. Once you master it, you have it for the rest of your life.” A 2004 study published in the Archives of Internal Medicine concluded that for young and middle-aged patients in particular, CBT-I was more effective than sleeping pills in helping people fall asleep faster and sleep more soundly through the night.

Finding a specialist trained in sleep-related cognitive behavioral therapy isn’t always easy, however, since the field is relatively new. (For a nationwide list, check out the American Academy of Sleep Medicine at www.aasmnet.org). Cost is also an issue. While health insurance plans typically pay for insomnia drugs, many policies don’t cover psychotherapy.

Cognitive-behavioral therapy also takes work on the part of a patient. “But as I tell my patients, the work you put into it can really pay off long-term by permanently improving the quality of sleep,” Kuo says. Better sleep can boost your energy and improve your outlook on life. And as the latest research shows, it can also prevent or ease depression.