12-3-98, NEW YORK CITY, NEW YORK, UNITED STATES, Young woman receives light therapy for the … [+]
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Major depressive disorder is a debilitating disability that affects everyone 5% of adults worldwide. Although doctors commonly prescribe antidepressants to patients, it may not benefit everyone and has various side effects. A non-pharmacological solution that could effectively treat depressive disorders could be bright light therapy. According to a recent study, patients with perennial depression treated with bright light therapy reported a 40% remission rate.
“The main supporting argument in favor of using bright light as an additional treatment is the cost. Even though the costs of outpatient antidepressant treatment are highly variable, exposure to external light generally entails no costs or limitations, reinforcing the need to enhance bright light therapy as an efficient adjunctive treatment for perennial depressive disorders.” , the researchers wrote in their study. that was published in JAMA Psychiatry.
Previous studies have shown that light exposure can affect people’s mood and cognitive functioning. Researchers say this happens when bright light penetrates the inner surface of the retina, where neurons called retinal ganglion cells are located. These neurons then transmit visual information from the retina to the brain and also play a role in influencing your brain’s ability to regulate your mood, especially as these neurons relay visual information to areas of the brain responsible for mood regulation such as the amygdala, suprachiasmatic nucleus, and dorsal raphe nucleus.
To delve deeper into how bright light therapy could help treat perennial depression, the researchers analyzed data from studies that included 858 participants diagnosed with major depressive disorders. The study participants had to sit in front of a fluorescent light box that produced extremely bright white light of 10,000 lux for at least 30 minutes daily. “Patients treated with bright light therapy had a significantly higher remission rate than the control groups,” the team noted. “These findings suggest that bright light therapy was an effective adjunctive treatment for perennial depressive disorder, and that response time to initial treatment may be improved by adding bright light therapy.”
“Our results do not underline the need for randomized clinical trials with longer follow-up periods, but strengthen the theory that patients treated with bright light therapy achieve faster remission of symptoms and a faster response rate than patients treated with antidepressants alone,” added the authors add.
For 30 years, bright light therapy has been used to treat sleep disorders such as sleep phase syndrome, which is characterized by people not falling asleep until several hours after midnight and having difficulty waking up in the morning.
Bright light therapy works by slowly adjusting and shifting people’s sleep patterns. The light boxes are also used during winter to treat seasonal depression in the Global North.
Your healthcare provider should determine the appropriate duration of exposure to bright light and the appropriate light intensity. Research has shown that bright light therapy may work best in combination with antidepressants.
While these results are encouraging and demonstrate the potential of bright light therapy, purchasing a light box and using it at home may not be as effective. “Some devices advertised as ‘10,000 lux’ devices produced this intensity only at unreasonably short distances, over a limited field, or with unacceptable glare or irregular illumination. Device selection is critical to ensuring patients receive evidence-supported doses receive light,” researchers wrote in one Study from 2019.