Light Therapy Might Help People With Bipolar Depression
As the months grow colder and darker, many people find themselves somewhat sadder and even depressed.
It’s unclear how lack of light might cause the winter blues, although some suggest that the dark days affect the production of serotonin in the skin.The idea with light therapy for depression is to replace the sunshine lost with a daily dose of bright white artificial light. (Antidepressants, psychotherapy and Vitamin D help, too, according to the National Institute of Mental Health.) The light box is actually more like a screen, the size of an average desktop computer. Some people call it a “happy box.”To test its usefulness in treating bipolar disorder, researchers at the Feinberg School of Medicine, Northwestern University enrolled 46 patients who had at least moderate bipolar depression. Half of participants were assigned to receive bright light therapy. The other half received a dim red placebo light. They also kept taking their regular medication.
First, the results in this study are “intriguing, but highly preliminary,” according to Al Lewy, a psychiatrist and professor emeritus at Oregon Health and Science University who was one of the pioneers of light therapy to treat SAD.
And given that light therapy can trigger hypomania, Lewy says that the therapy should be conducted under a doctor’s supervision, preferably a psychiatrist. “If there’s the slightest chance that a patient will switch into a manic episode, then their doctor can be there to treat them.”
Bipolar disorder, also known as manic-depressive illness, is a brain disorder that causes unusual shifts in mood, energy, activity levels and the ability to carry out day-to-day tasks, according to the National Institute of Mental Health. About 3 percent of the U.S. adult population suffers from the disorder.
This study “offers a glimmer into a new pathway for treatment,” says psychiatrist Ken Duckworth, medical director of the patient advocacy group National Alliance on Mental Illness. That’s needed, he says, because “bipolar depression is one of the most difficult types of depression to treat.” Medications such as mood stabilizers and antidepressants that work well to treat the manic phase of bipolar disorder are not effective in treating the depressive phase, Duckworth says. And people with bipolar disorder “spend most of their time on the depressive end of the spectrum.”
Sit says it’s important to see her findings duplicated in future research, which should also investigate how the light affects the body’s circadian rhythms at different times of day, and how that affects bipolar symptoms.
NEIGHMOND: Sit wants to see her findings duplicated in more studies. And she says future research should measure internal body clocks to see whether slumps or upswings in energy effect bipolar depression and whether other brain changes occur. And there’s an important caveat for people with bipolar disorder.
AL LEWY: The new study is intriguing but highly preliminary.
NEIGHMOND: Psychiatrist Al Lewy with Oregon Health and Science University says patients with bipolar disorder need to consult with their doctor before trying light therapy. This is mostly because the timing of the therapy can make a big difference, especially for people with bipolar disorder who experience intense highs and lows.
LEWY: If you do the light, particularly in the morning, with bipolar depression, you might cause the person to switch into a manic episode.
NEIGHMOND: Which is why patients in the study got their light therapy in the middle of the day. The cycle of highs and lows make bipolar depression much more difficult to treat than other types of depression. Psychiatrist Ken Duckworth, medical director of the National Alliance on Mental Illness, says that’s because medications like mood stabilizers and antidepressants work well to treat the manic phase of the disorder but not the depressive phase.
KEN DUCKWORTH: People with bipolar disorder spend most of their time on the depressive end of the spectrum. And this difficulty is compounded by the fact that we don’t have very good treatments for the depressive phase of bipolar disorder.
Transcript provided by NPR, Copyright NPR.