Ask The Experts: What Causes Seasonal Affective Disorder?
Kyle Graper, MD, is a family medicine physician with Franciscan Physician Network. He answers your questions about seasonal affective disorder and approaches to treating it.
Q: I seem to get a little depressed when summer is gone and winter approaches. I think I might have Seasonal Affective Disorder. How might I know if I have it?
A: Seasonal affective disorder (SAD) is a type of mood disorder that coincides with the change in seasons. The most common form of SAD is depression starting when the season changes from fall to winter, often called winter depression. People affected by this disorder will experience some or all of the classic symptoms of depression which include:
- Depressed mood
- Loss of pleasure or interest
- Change in appetite (decreased or increased)
- Change in sleep pattern (decreased or increased)
- Poor concentration
- Lack of energy
- Feelings of guilt, and some may have suicidal thoughts.
Unlike other types of depression, if left untreated, SAD usually improves when spring arrives.
Q: What Causes Seasonal Affective Disorder?
A: The exact cause of SAD is not known. There are several hypotheses out there, one of which is related to the body's mechanism for regulating sleep-wake cycles, known as the circadian rhythm. Our bodies naturally produce a hormone in response to the light/dark cycles, and it is believed that the shorter hours of daylight in winter months throws off this cycle. This may be the reason why some people with SAD may notice that their symptoms improve when the sun is shining in winter months.
Clues that you may have SAD include a history of depression that coincides with changes in the season, your symptoms are usually worse in winter and you may notice improvement in symptoms on sunny days.
Q: How Can I Treat Seasonal Affective Disorder?
A: Treatment options for seasonal affective disorder include medications to treat depression, phototherapy and counseling. It is also encouraged that individuals practice good sleep hygiene and get regular exercise. If you think you may have symptoms consistent with SAD, please see your doctor to be evaluated.