Carol Landau, PhD - Seasonal Affective Disorder
Those of us who live in the Northeast, Midwest and even parts of the Mid-Atlantic states have been struggling with the effects of the most severe winter in recent memory. Burdened by ice, snow, and disruptions in schedules, gloom can set in. For some people, however, the situation is more serious, because they suffer from seasonal affective disorder. Seasonal affective disorder, or the acronym SAD, was first described in the mid-1980s. It is now categorized as one type of the major depressive disorders. A major depressive episode is not merely the transient blues but a condition that interferes with daily activities and causes severe emotional pain. SAD is a recurring depressive episode that begins in late fall and remits in the spring.
My patient Gwen illustrates the SAD pattern of depression. Normally a high functioning, funny woman with a successful career in graphic design, Gwen had dreaded the winter months for many years. Before she came for treatment, some time in October, she would begin to feel lethargic and irritable with her husband and four year old daughter. Gwen would sleep more but still feel tired and started craving and eating sweet carbohydrates. By late November she would have gained up to 10 pound and was consequently furious with herself. Gwen also felt “leaden.” These symptoms are the opposite of the more typical depressive episode, which include loss of appetite, weight loss and insomnia. The New Year was never a time of beginnings for Gwen but rather one of hopelessness and irritability.
As with the other depressive disorders, SAD occurs more often in women than men. Not surprisingly, seasonal affective disorder occurs more often, although not exclusively, in people living in the northern latitudes. Estimates of the prevalence of SAD range from 1-10%, with another 10-20 % reporting some symptoms. Research shows that people with seasonal affective disorder have a predisposition toward depression, which is triggered by the lack of daylight. One hypothesis is that SAD is a disturbance of circadian rhythm and abnormal metabolism of melatonin. Another hypothesis has gained more support--that there is a depletion of serotonin, the neurotransmitters associated with mood.
What is clear is the effectiveness of light therapy. Exposure to fluorescent light of 2,000-10,000 lux (a measure of the intensity of illumination) reduces the symptoms of SAD within days. Using 10,000-lux light, treatment begins with 15 to 20 minutes, increasing to 30 minutes a day. Eyes need to be open during the treatment but not looking directly at the light. Commercially produced light boxes are recommended because they diffuse the light and therefore prevent any retinal damage. The light therapy should be continued throughout the winter months until more exposure to the sun can occur naturally.
Apparently, some have mistakenly turned to tanning salons to treat SAD. This is wrong on a number of levels! Tanning booths do not use 10,000 lux light, eyes are covered, and they do expose people to the harmful ultraviolet rays that promote skin cancer.
Antidepressants including the SSRIs--selective serotonin reuptake inhibitors--are also effective, especially for those who have had a positive response in the past. Current research is focusing on the treatment and prevention of SAD. The medication bupropion or Welbutrin has been shown to prevent the onset of SAD. Nutritional interventions are also being developed, including beverages that include tryptophan, the amino acid precursor of serotonin.
Gwen now “fires up the light box” every fall. In psychotherapy we work on Gwen’s relationships so that she can have more social support and on getting more exercise because her depressive symptoms tend to lead to isolation and lethargy. She’s no longer afraid of winter.
For Gwen, and for all of us, let's hope that spring will be here soon.