Behavioral Health Articles

Seasonal Affective Disorder

by Joan Martin

December is designated as Seasonal Affective Disorder (SAD) Awareness Month.

Many people experience mild depression at this time of year, usually due to the stress of preparing for holiday events, financial pressures, or unrealistic holiday expectations. A more serious form of winter blues is Seasonal Affective Disorder (SAD). According to Dr. Angelos Halaris of Loyola University, SAD sufferers experience “depression, exhaustion and lack of interest in people and regular activities.” Other symptoms include increased appetite, weight gain, oversleeping, irritability, and trouble concentrating. If left untreated, SAD may interfere with an individual’s ability to work, sleep, or function in social situations. It is a cyclical condition; symptoms usually start in the fall, lessen in spring, and disappear in summer. Both Winston Churchill and Abraham Lincoln experienced significant episodes of SAD.

What causes SAD? The condition is “thought to be related to a chemical imbalance in the brain brought on by lack of light due to winter's shorter days and typically overcast skies," states Dr. Halaris. One theory is that levels of serotonin, a mood-regulating brain chemical, drop as sunlight levels decrease in fall and winter. Another theory involves melatonin, a hormone which encourages sleep; people with SAD produce more melatonin in wintertime. Also, the body’s internal clock that regulates sleep-wake cycles may be altered as the sun rises later and sets earlier. Disruptions in these sleep-wake cycles, called circadian rhythms, may cause depression. People with SAD often have family members who also experience SAD or clinical depression, suggesting a genetic link.

According to the American Psychiatric Association, 10 to 20 percent of Americans experience mild forms of SAD, and up to four percent have more serious forms. It is twice as common in women as in men. Symptoms usually begin in early adulthood but occasionally occur in children. Interestingly, geography plays a significant role; rates of SAD are higher in northern states than in southern states. Rates are also high in countries such as Sweden and Iceland, probably because the amount of sunlight available in winter decreases as latitude increases. Iceland even has a traditional word, skammdegisthunglyndi, which means “short-day-heavy-mood.” People living near the equator almost never develop SAD; however, people who move from countries near the equator to countries at northern latitudes often notice signs of depression after a few months in their new location.

You can take steps to prevent SAD or treat mild symptoms. "If at all possible, get outside during the winter, even if it is overcast. Expose your eyes to natural light for one hour each day. At home, open the drapes and let in natural light," Dr. Halaris recommends. Regular exercise, either indoors or outdoors, also increases levels of mood-elevating hormones. Talk to a friend about any concerns, try to minimize stress, and, if possible, take a mid-winter vacation in a sunny location.

If symptoms persist after the holidays or don’t improve with exercise and exposure to sunlight, talk to your primary care provider. SAD can be "effectively treated with light therapy, antidepressant medication and/or psychotherapy,” says Dr. Halaris. Bright Light Therapy (BLT), or phototherapy, involves sitting in front of a special light box for about an hour daily; this reduces or eliminates symptoms in 50 to 80 percent of people within a few days. BLT was developed by Dr. Norman Rosenthal of Georgetown Medical School, who experienced SAD symptoms after moving from South Africa to New York. Light boxes can be purchased for home use, and head visor versions even allow users to walk around. Never use suntan lamps or tanning beds for BLT; these emit UV rays which harm the eyes and skin.

For more on SAD, check out Dr. Rosenthal’s book, Winter Blues: Everything You Need to Know to Beat Seasonal Affective Disorder, or www.nami.org. Even here in Central New York, gloomy skies and winter cold don’t have to get you down.

Joan Martin is a project assistant at Seven Valleys Health Coalition.