Light therapy, the treatment of choice for seasonal affective disorder
(SAD), may improve nonseasonal depression, bipolar disorder, pregnancy and
postpartum depression, and other psychiatric disorders, new studies
Manipulations of the sleep/wake schedule also hold promise for correcting
circadian rhythm disturbances common in such disorders, improving mood,
cognition, and neurobehavioral function.
Specialists in chronotherapeutics—treatments aimed at resetting
malfunctioning biological clocks—are stepping up efforts to educate
other clinicians about these therapies, reported Michael Terman, Ph.D., a
professor of clinical psychology in psychiatry and director of the Center for
Light Treatment and Biological Rhythms at Columbia University College of
Physicians and Surgeons in New York.
Light therapy remains both under-used and abused, Terman told
"Some clinicians tell patients to try a light box without knowing how
to present and dose light therapy," he said. "That often leads to
Consumers who self-treat, using light boxes purchased on their own, he
noted, may not get better and thus give up on therapy. Light devices,
available from many suppliers, lack federal regulation.
Terman and colleagues established a nonprofit international organization in
1994 to foster education and research in chronobiology for professionals and
patients. That organization, the Center for Environmental Therapeutics (CET),
he asserted, "is a multidisciplinary academic department that could not
exist at any university."
The CET's Web site provides access to an automated morningness-eveningness
questionnaire, a validated self-assessment tool that predicts the onset of
melatonin secretion, a marker of time on the body's clock. The clinician needs
to know when melatonin secretion starts, Terman said, to prescribe light at
the right time to shift biological clocks earlier or later.
The CET has launched a Web site for clinicians, at<www.chronotherapeutics.org>,
where a privacy-protected, moderated forum modeled on hospital rounds aims to
promote discussion of complex cases and interaction with colleagues. This Web
site also offers clinical assessment tools designed and produced at Columbia
University's New York State Psychiatric Institute. These include structured
interviews for rating the severity of depression and hypomania, sleep logs,
and a questionnaire for monitoring possible adverse effects of light
In patients with bipolar disorder, sleep deprivation for a full night or
only the second half of the night has been known for over 30 years to elicit a
rapid antidepressant response, according to Francesco Benedetti, M.D., a
professor of psychiatry at the University Vita-Salute San Raffaele and
director of the psychiatry and clinical neurosciences research unit at San
Raffaele Hospital in Milan, Italy.
Because most bipolar patients relapse after recovery sleep, sleep
deprivation initially was not thought clinically useful, he said. Using
repeated sleep deprivation—now called wake therapy—in combination
with light therapy and lithium, however, he and colleagues have achieved
sustained remission rates ranging from 50 percent to 75 percent, better than
is expected with antidepressant medications, in hundreds of patients.
Combination therapy also shortens hospitalization.
In both seasonal and nonseasonal depression, light and sleep manipulations
may permit tapering or stopping antidepressant medications, noted Anna
Wirz-Justice, Ph.D., an emeritus professor of psychiatric neurobiology at the
Center for Chronobiology of the University of Basel in Switzerland. In
pregnancy and postpartum depression, such therapies may serve as safe
alternatives to antidepressant medications. Wirz-Justice is conducting a
five-year double-blind, placebo-controlled trial of light therapy in major
depression in pregnancy. Researchers also are exploring chronotherapeutics in
attention-deficit/hyperactivity disorder, dementia, Parkinson's disease, and
Wirz-Justice, Terman, and Benedetti are coauthors of a new book,
Chronotherapeutics for Affective Disorders: A Clinician's Manual for Light
and Wake Therapy.
The Society for Light Treatment and Biological Rhythms will hold its
annual meeting June 24 to 27 in Berlin, Germany. The program is posted at<www.sltbr.org>.
The Web address of the Center for Environmental Therapeutics is<www.cet.org>.▪