Seasonal Affective Disorder: Causes and Treatment Options
Seasonal Affective Disorder (SAD) was first noted before 1845, but was not officially named until the early 1980’s. As sunlight has affected the seasonal activities of animals (i.e., reproductive cycles and hibernation), SAD may occur in humans due to this seasonal light variation. As seasons change there is a shift in our circadian rhythm. This is due partly to the changes in sunlight frequency and duration. The result is having our biological clocks fall out of “step” with our daily schedules. As the days get shorter the problem may worsen.
SAD is a common condition that affects people year after year, and tends to be worse in January and February. It can vary from being quite severe, to being a relatively mild problem. Some of the symptoms are: decreased energy, difficulty waking up in the morning, oversleeping, overeating (especially sweets and starches); and because of this overeating and inactivity can lead to weight gain. Often people with SAD have difficulty concentrating and getting their work done. They also may withdraw from friends and family and ultimately feel anxious, irritable, and yes — sad.
For many of us working nights in the sleep center it is probably even more prevalent among sleep medicine technologists. In order to understand this disorder let’s look at the etiology, ways to prevent it and treatment for SAD.
Causes of Seasonal Affective Disorder
SAD is caused by three main factors. The problem could be inadequate exposure to light. Inadequate light exposure may be for non-seasonal reasons; for example, people in basement apartments, windowless offices, or working nights in poorly lighted areas. Also, periods of extended cloudiness any time of the year may cause people to have symptoms of SAD. Certain people are also more susceptible to SAD: those with a family history and women, more than men by a factor of three to one. People living in the north are also at greater risk for developing SAD, due to less exposure to natural light. Finally, stress combined with the other two factors can make the symptoms of SAD much worse, than someone with simply less exposure to light.
To differentiate between normal depression and SAD, one has to consider the time frame and that season affective disorder is a type of depression, but occurs regularly. If this occurs in a person regularly at Thanksgiving, and Christmas; and he or she is usually the life of the party any other time of the year, then the glum and withdrawn behavior would be consistent with symptoms of SAD. If you have the symptoms year after year, and more in the winter than in the summer, chances are you have SAD as opposed to normal depression.
In people with SAD, sunlight can actually make them less depressed. While there are many people who do not have symptoms that are bad enough to warrant going to a doctor, there are those who still feel somewhat down in the winter. Maybe they are less productive or creative or maybe they just don’t enjoy life as much during the winter. These people we describe as having “winter blues” which is a milder form of SAD. The good news is that winter blues responds to the same kind of treatment that is effective for those with SAD.
Additionally, SAD is more common in the Northern Climates. For example, in one study, SAD occurred in only 1.5% of people in Sarasota, Florida, but in almost 10% of people in New Hampshire.
SAD does not only happen in the winter season. There are some people who get depressed every summer year after year. It is believed that they have difficulty dealing with the heat of summer. SAD can develop in people who previously have not had a problem with it due to several factors:
- Relocation from the south to the north.
- Moving a home or office to a new location that has darker lighting.
- Children develop SAD as they grow (In girls it typically appears after puberty.)
- Anything that blocks the entry of light into the eyes — for example cataract development or using light blockers to promote sleep when working night shift — can precipitate SAD.
Who Gets Seasonal Affective Disorder?
SAD can affect people of all ages, including teens. Teens are commonly affected by SAD, and in one research study results showed that by the time children get to high school; approximately 5% have developed SAD. This is about as common as in adults. It is also worth noting that the winter blues is even more common than SAD, affecting about 15% of the adult U.S. population. So if you add the numbers affected by SAD and those affected by the winter blues, about 1 in 5 Americans is affected and could use extra light in winter. So those of you working nights in the sleep center have not brought it on, but because of your working hours you are at greater risk.
The holiday season typically presents a special challenge to people with SAD. Holidays involve many chores and demands. Cards need to be written, gifts purchased and wrapped and the usual round of social events attended. All of these things can pose major stresses for people with SAD and can make the symptoms worse. However, it is also worth mentioning that some people get blues around the holidays for completely different reasons which appear to be related to emotional reactions to the holidays.
SAD can last up to five or six months of the year. It’s very important to realize that we’re not dealing with brief holiday blues, but with a condition that can affect almost half of a person’s life. January and February tend to be the worst months. There is hope however. Evidence seems to suggest that for women, SAD improves after menopause. Others adjust to SAD so well that their symptoms disappear. One study showed that 1/3 of people with SAD reported no longer having symptoms several years after first being diagnosed. Chronic fatigue syndrome, unlike SAD, affects people all year round. SAD specifically affects people during the dark days. Many of the symptoms of SAD, such as overeating, weight gain and depression, are not typical of chronic fatigue syndrome.
People with SAD are often either sleepy or fatigued. The first one, as you know, means drowsy, the other means lacking energy and many patients have difficulty differentiating between the two. People with SAD can have either recurrent depression with normal intervening periods or recurrent depression with exaggerated energy and vitality in the spring and summer months. This latter group can also be as a result of bipolar disorder.
People suffering from bipolar disorder need to be extra careful in using any antidepressants and this includes light therapy because it can make them over-energized or promote mania in rare cases.
If you have determined that you may have SAD, finding a physician that knows about SAD should be your first priority. Since the disorder has only been recently described it may be more difficult to find a physician with experience in treating it. Physicians who do not keep up with the literature can be surprisingly uninformed about it. If your doctor or therapist says they don’t believe in SAD or don’t know much about light therapy, you may want to try someone else.
Treatment of Seasonal Affective Disorder
The first step, obviously, is to get more light. Light therapy alone has resolved the disorder in 85% of those diagnosed with it. Light therapy is available in a number of ways. Getting outdoors on a bright winter day, or bringing more light into the home are two ways almost everyone can self-help. The best way for people with SAD to predictably and consistently get more light is with special light boxes or fixtures. These are available through a number of commercial manufacturers; many of which are accessible through Websites. There are several commercial manufacturers who distribute quality light boxes. It is recommended to use a light box from a reputable company rather than trying to create your own light box.
For those working nights it is best to use the light box either during the night, or before going into work after the sleep period. This is to prevent resetting your circadian rhythm before attempting to initiate sleep. The most difficult months for SAD sufferers are January and February, and younger persons and women are at higher risk. It is important however to utilize therapy properly. Sometimes people may need 45 minutes twice a day of proper bright light therapy. This can be combined with a special technique that turns the bedside lamp on before waking up. The device is called Dawn Simulator. The light boxes that are currently used for treatment with light therapy all use artificial light. Generally these are fluorescent lights set in a metal frame behind a plastic diffusing screen. It is very important to use the right kind of light because staring at incandescent lights can damage the eyes. So be sure to use a proper light box or the newer glasses with lights that have become available in recent years.
The use of tanning booths is not a way of treating SAD as there are no good studies of tanning as a treatment for SAD. In fact, the light therapy that is used in treating SAD is not ultraviolet light at all, but visible light that appears to work by passing through the eyes. In contrast, when utilizing a tanning salon your eyes are usually covered and the skin is exposed to ultraviolet light. But some patients with SAD have anecdotally reported a mood lift after such tanning sessions. They can’t be generally recommended, however, because of the risk of skin cancer as a result of ultraviolet light exposure.
For those that tend to get migraine headaches from bright light, starting with dimmer lights and gradually increasing the brightness may decrease the headaches. If that still doesn’t work, antidepressant medicines may help.
Insurance companies sometimes cover the cost of light therapy, specifically the purchase of a light fixture. But reimbursement is very much a hit and miss affair. Some of the light box companies will provide sample letters to your doctor to send to your insurance carrier to help you get reimbursement.
Other treatments for SAD include exercise, stress management, dietary control, and vacations in the south.
For those afflicted with SAD, diet may play an important role. Many people with SAD have an insatiable appetite for carbohydrates, however it is recommend that carbohydrates be limited. The trouble is the more you eat, the more you want and this of course will lead to weight gain. For those with SAD it is best that meals be limited to two per day where protein and salad are predominant, and then by mixing carbohydrates into the third meal. This is the essence of most dietary recommendations.
There is a connection between eating disorders and SAD as well, more specifically bulimia (the tendency to binge eat). People who have this tend to experience worsening symptoms during the winter months, and may benefit from light therapy. This behavior in a teen girls may be associated with SAD. So if you’re affected by SAD, try to purchase a light box. Book a winter vacation in the Caribbean. Minimize the stresses over the winter. Get your exercise program in place. When those dark days hit, you’ll be good and ready.
This article was previously published in the A2Zzz Volume 13, Number 4, Winter/Spring 2005