Newswise &emdash; A study commissioned by the American Psychiatric Association and led by a psychiatrist at the University of North Carolina at Chapel Hill School of Medicine has found that light therapy effectively treats mood disorders, including seasonal affective disorder (SAD) and other depressive disorders.
A report of the study, which appeared April 1 in the American Journal of Psychiatry, also finds that the effects of light therapy, also known as phototherapy, are comparable to those found in many clinical studies of antidepressant drug therapy for these disorders.
The findings were based on a meta-analysis, a systematic statistical review of 20 randomized, controlled studies previously reported in the scientific literature. These represented only 12 percent of 173 published studies that the authors had originally considered for review.
“We found that many reports on the efficacy of light therapy are not based on rigorous study designs. This has fueled the controversy in the field as to whether or not light therapy is effective for SAD or for non-seasonal forms of mood disorders,” said lead author Dr. Robert Golden, professor and chairman of psychiatry at UNC and vice dean of the medical school.
“But when you throw out all the studies that are methodologically flawed and then conduct a meta-analysis of those that are well-designed, you find that light therapy is an effective treatment not only for SAD but also for depression.”
The use of bright artificial light for people with SAD, a recurring depression that develops in the fall or winter and spontaneously disappears during spring or summer, was first described in the Archives of General Psychiatry in 1984. Since then, the treatment has been tried in clinical and research programs for non-seasonal mood disorders, Alzheimer’s disease, jet lag, insomnia, eating disorders and other behavioral problems.
