Overview
For nearly two decades, researchers have realized the therapeutic
potential of light as a treatment for Seasonal Affective Disorder ("SAD" or
"winter depression"), various types of sleep disorders, and jet lag.
Bio-Brite ha pioneered the development and marketing of light therapy
devices based on the work of scientists at the National Institute of Mental
Health in Bethesda and Thomas Jefferson University in Philadelphia. These
products include light visors, dawn simulators and programs designed to
control individuals' exposure to light. A brief summary of these products
and their scientific foundations follows.
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Seasonal Affective Disorder
Data from a large number of controlled clinical trials conducted during
the last fifteen years has repeatedly demonstrated the clinical efficacy of
light to treat SAD. Response rates have equaled or exceeded commonly used
antidepressant drugs. In 1998, the Archives of General Psychiatry published
the results of two large scale controlled trials conducted by over
three-to-four year periods demonstrating the positive results of light
therapy. The studies are even more compelling than earlier trials because of
the large numbers of patients involved and the use of ion generators as a
placebo control. The difficulty of finding a placebo for bright light led
earlier researchers to use lower intensity light as a placebo, and patient
response to this lower intensity light was relatively frequent. While it is
quite likely that the results occurred because lower level light is
therapeutic for some patients, later researchers searched for an effective
placebo. Clinical trials have convinced even the most skeptical scientists
that light therapy can be effective.
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The Light Visor
The Bio-Brite Light VisorT is the result of scientific study focused on
developing a mobile light source capable of delivering light therapy without
severely restricting movement or limiting activities of patients receiving
the therapy. The first light therapy devices were light boxes. Early models
were large, heavy, and awkward to move around. Current models have been
greatly refined and are much easier to transport; however, these devices
necessarily confine the patient to remaining adjacent to stationary boxes
while receiving light therapy. The restrictive nature of light boxes and
their concomitant effects on patients' quality of life led pioneering
scientists in the field, including Dr. George Brainard of the Thomas
Jefferson University College of Medicine, and Drs. Norman Rosenthal and
Thomas Wehr of the National Institutes of Health, to experiment with
head-mounted, battery- operated units capable of shining bright light into
patients' eyes without requiring the recipients to remain immobile.
Bio-Brite worked with these investigators to develop and market a
lightweight, easy to use, mobile head-mounted device, now trade-marked as
the Bio-Brite Light VisorT. The Visor has been tested in controlled clinical
trials. The earliest, in 1992, was in fact the largest single trial
conducted in one season on the use of light to treat SAD (Joffe, R.T., et.
al.; Psychiatry Research, 46, 1993). There were more than 100 patients
involved. The response rate was good, comparable to light boxes, however,
some patients responded to low Visor light intensities, raising the placebo
issue. In retrospect, based on current knowledge of the biological effects
of light on humans, a feasible argument can be made that under the
circumstances of the experimental design, low intensity light might have
been effective for some people. Nevertheless, a recent review of published
data from light box trials and head mounted units (HMUs) trials by two
authoritative clinicians, led them to conclude that HMUs produce response
comparable in response rates similar to light boxes for SAD (Seasonal
Affective Disorder and Beyond: Light Treatment for SAD and Non-SAD
Conditions. Ed. Lam, R. W., American Psychiatric Press, Inc, Washington, DC,
1998). In evaluating clinical results of Visor trials, some investigators
have ignored, or are not aware, that four different models of the Visor have
been marketed by Bio-Brite. Each model incorporates improvements over
earlier models. Therefore, data from the first prototype model cannot fairly
be compared with data from more current models. Design problems with the
Visor principally relate to filling the field of vision of users with light,
yet not obstructing vision. This is a considerable challenge, considering
anatomical differences of human heads. The design of the relatively new LED
model has significantly addressed this problem. The light bar is located
further forward, directing light to the eyes at less of an angel, and an
array of LEDs provides a much larger area of light to the eyes. Dr. George
Brainard, Jefferson Medical College, an acclaimed expert on the biological
effects of light in humans, and Dr.Brenda Byrne a clinical expert on SAD, at
the same institution, have conducted controlled clinical trials to measure
the effect of the LED model Visor on melatonin ("the light hormone")
suppression in normal human volunteers. The data, which are currently in
preparation for publication, and were presented at the annual meeting of the
Society for Light Treatment and Biological Rhythms (SLTBR),1999, clearly
demonstrated that LED Visor light can significantly suppress melatonin, an
important marker for the biological activity of light. During the last SAD
season, prominent clinical investigators at Yale Medical School, and
Jefferson Medical College, conducted an open trial of the LED Visor in SAD
patients. All of the 10 patients who completed the study responded very
well, and were pleased with the Visor. These results were reported at the
2000 annual meeting of the SLTBR, and can be found in the published
abstracts, Vol. 12, of this society.
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Sleep Disorders
It has long been known that daylight is a critical signal in keeping the
"biological clock" (circadian rhythms) on time, consequently regulating the
sleep wake cycle in humans and lower animals. Two relatively common sleep
disorders, sleep phase delay, and sleep phase advance, have been recognized
in humans. These disorders may respond to bright light therapy. Sleep phase
delay, inability to initiate sleep, and to awaken at relatively normal times
is most frequently observed in adolescents and young adults, and may be
treatable with 2-3 hours of bright light therapy applied in the morning for
several days. Sleep phase advance, falling asleep, and wakening too early,
is common in the 65 years plus age group, and can be treated with bright
light applied in the evenings. These disorders can be complicated to treat,
and we recommend that people with these problems consult a sleep-medicine
specialist. A summary of relevant published data was published recently in
Sleep, Vol. 22, No. 5, 1999. Jet lag is classified as a sleep disorder,
which simply stated is the inability of the biological clock of the
jet-airplane-traveler to normally reset rapidly to a new time zone.
Bio-Brite has devised a program involving the Light Visor that manipulates
light to rapidly reset the biological clock. The program is soundly based
scientifically, and it's efficacy is supported by a number of antidotal
reports by users. Bio-Brite has recently received a Small Business Research
grant from the National Institutes of Health to support a controlled field
trial of the program in normal human volunteers. Melatonin has been reported
to be helpful in preventing jet lag. However, a large controlled field trial
failed to demonstrate efficacy (Spitzer, R.L., et. al.; American J
Psychiatry 1999; 156). Furthermore, melatonin is still considered by
scientists to be an experimental drug, and "over-the-counter" preparations
are not regulated by the FDA.
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