Or Could it be “SAD”?
Philip A. Gilly, MD, FAAFP
Family
Practice Board Certified
Many people complain of feeling down, having less energy, putting on a few pounds, and having difficulty getting up in the morning throughout the dark, short days of winter. Some people notice that the symptoms return each winter, and are bothered by them, but remain fully functional. As much as 25 per cent of the population at the middle-to-northern latitudes of the United States experience "winter doldrums."
But some people have more severe bouts of feeling down all the time, low energy, problems with sleep and appetite, and reduced concentration to the point where they have difficulty functioning at work or in the home. We say that these people have a clinical depression , to distinguish it from everyday ups and downs. Seasonal affective disorder (affective is a psychiatric term for mood), or SAD, is the diagnosis given to people who have these clinical depressions only during the autumn and winter seasons. During the spring and summer, they feel well and "normal".
People suffering from SAD experience these and other symptoms to such a degree that they feel unable to function normally. They often feel chronically depressed and fatigued, and want to withdraw from the world and to avoid social contacts. They may increase their sleep by as much as four hours or more per day, have greatly increased appetite - sometimes accompanied by irresistible cravings for sweet and starchy foods - and gain a substantial amount of weight. Women frequently report worsening of premenstrual symptoms. People with SAD suffer in the extreme the kinds of changes which many others experience to a much lesser degree in wintertime.
An individual SAD sufferer, however, need not show all the symptoms described above. Sleep duration, for example, may be normal, while carbohydrate craving may be extreme - or vice versa. Sometimes a symptom in the cluster is actually opposite the norm, such as insomnia as opposed to excessive sleep. A diagnosis of SAD requires a professional evaluation by a clinician who is experienced in recognizing it, such as your Family Physician, or a psychiatrist, psychologist, or social worker. You are cautioned against attempting self-diagnosis as it is easy to misinterpret symptoms or incorrectly rate their severity.
Recent studies indicate that about five times as many people may suffer from "winter doldrums," a sub-clinical level of SAD, as suffer at the level of clinical severity. Anyone who is significantly depressed should be assessed by their family doctor because some physical problems can show up as depression and because light therapy may be harmful to people with certain medical conditions (for example, eye disease).
An exciting new research finding is that many patients with SAD improve with exposure to bright, artificial light, called light therapy, or phototherapy. As little as 30 minutes per day of sitting under a lightbox results in significant improvement in 60% to 80% of SAD patients. Side effects of light therapy are mild, although people with certain medical conditions or taking certain medications should avoid light therapy. Other treatments for depression, including antidepressant medications and counseling , may also be helpful for patients with SAD. People with milder symptoms of the "winter blahs" may be helped by simply spending more time outdoors and exercising regularly in the winter.
It isn't known exactly how light therapy works, but research shows that light has a biological effect on brain hormones and function. One theory is that people with SAD have a disturbance in the "biological clock" in the brain that regulates hormones, sleep and mood, so that this clock "runs slow" in the winter. The bright light may help to "reset the clock" and restore normal function. Other theories are that changes in brain chemical (neurotransmitter) function, particularly serotonin and dopamine, may be disturbed in SAD, and that these neurotransmitter imbalances are corrected by light therapy and/or anti-depressant medications. Still other scientists believe that patients with SAD have reduced retinal light sensitivity in the winter that is corrected by light therapy.
Light therapy involves exposure to intense levels of light under controlled conditions. The recommended light therapy system consists of a set of fluorescent bulbs installed in a box with a diffusing screen, and set up on a table or desk top at which one can sit comfortably for the treatment session. Treatment consists simply of sitting close to the light box, with lights on and eyes open. Looking at the lights is not necessary or recommended; rather, people are free to engage in such activities as reading and writing, or eating meals. What is important is to orient the head and body toward the lights, concentrating on activities on the surfaces illuminated by the lights, and not on the lights themselves.
Treatment sessions can last from 15 minutes to three hours, once or twice a day, depending on individual needs and equipment used. The average length of a session for a system delivering 10,000 lux illumination is, for example, much shorter than for 2,500 lux (30 minutes vs. two hours). In one clinical trial, all SAD patients showed remissions using a 10,000 lux system with UV-filtered light diffusion and angular tilt: 11% responded fully to 15-minute sessions upon awakening, 84% to 30-minute sessions, and 5% to one-hour sessions.
The time of day of light therapy is another important factor. Many people with winter depression respond best of all to treatment first thing upon awakening. Some, however, do better with evening light. It is necessary to determine the optimum time of day for each individual. Some very light-sensitive people, living and working in dim environments, may feel improvement with increased exposure to normal room light. Research studies show, however, that most sufferers of SAD and winter doldrums require exposure to light levels much higher than provided by ordinary indoor lamps and ceiling fixtures. Such therapeutic levels are five to twenty times higher (as measured in lux or foot-candles by a light meter) than typical indoor illumination in the home or office.
There are several books and magazine articles that are recommended for further reading. Most are available at bookstores or your public library.
For more information about SAD and Light Therapy, you can contact the Society for Light Treatment and Biological Rhythms (SLTBR), a non-profit organization of researchers, clinicians, manufacturers, and consumers dedicated to fostering research, professional development, and clinical applications. A public information package including information about light therapy, can be ordered by sending $7.00 and a stamped envelope to the society:
Francine Butler, Ph.D.
Executive Director of SLTBR
10200 W.
44th Avenue, Suite 304
Wheat Ridge, CO 80033-2840
Tel: (303) 424-3697
Fax: (303) 422-8894
website: http://www.websciences.org/sltbr/
E-mail: sltbr@resourcenter.com
This information provides a general overview on this subject and may not apply to everyone. Talk to your family doctor to find out if this information applies to you and to learn how to get more information. More health-related information is available on this and many other topics on the World Wide Web from Dr. Gilly’s Health Resource Directory and from the American Academy of Family Physicians.
References:
Raymond W. Lam , MD, FRCP(C), Info about
Seasonal Affective Disorder, UBC/VHHSC Mood Disorders Clinic website, 1996.
Research Foundation for Mental Hygiene, Questions and Answers About the Use
of Light Therapy in Winter, Columbia-Presbyterian Medical Center Winter
Depression Program website, 1995.
This handout was developed by Dr. Philip A. Gilly, MD. Permission is granted to reproduce this material for nonprofit educational purposes. Written permission is required for other uses, including electronic uses.