"These are the first systematic studies that indicate that SAD can actually be prevented in some patients by starting antidepressants early in the season, before the development of symptoms," comments Norman E. Rosenthal, M.D., Clinical Professor of Psychiatry, Georgetown Medical School, and one of the authors of the paper and leader of the research team that first described SAD over 20 years ago.
Dr. Rosenthal and colleagues performed a study with more than 1,000 patients with SAD from the northern United States and Canada. The patients, 70% of whom were women, reported an average of 13 previous episodes of fall-winter depression. Notwithstanding this long history, almost 60% of patients had received no previous treatment for their episodes of depression.
The researchers attempted to prevent the development of fall-winter depression though pre-emptive treatment with the antidepressant bupropion extended release tablets. One group of patients was randomly assigned to start treatment with bupropion-XL during the fall, while they were still well. Patients in the other group received an inactive placebo. The two groups were then followed over the winter season.
The relapse rate was 16% for patients taking bupropion extended release compared with 28% for those taking placebo. Early antidepressant treatment reduced the overall risk of fall-winter depression by about 44%. The antidepressant medication was generally well tolerated. When the patients stopped taking bupropion extended release in the spring, there was no increase in the depressio n relapse rate compared with the placebo group.
Patients with SAD have episodes of depression occurring in the fall and winter months. Although the cause is unknown, SAD appears related to reduced exposure to sunlight during the fall and winter in northern latitudes-genetic factors likely play a role as well. As in the current study, many patients with SAD are not treated with antidepressant medications, despite having many previous episodes of seasonal depression.
Starting antidepressant treatment in the fall offers a new option for reducing the rate of fall-winter depression in patients with SAD, the results suggest. "It is a highly novel approach to start treatment before the development of a major depressive disorder," says Dr. Rosenthal, author of the newly revised Winter Blues: Seasonal Affective Disorder: What It Is and How to Overcome It (Guilford Publications, 2005).
"The strategy makes sense when dealing with a condition where the pattern of relapse is somewhat predictable and the symptoms being prevented can be highly distressing and debilitating," comments Dr. Rosenthal. "In my opinion, the treatment used in the present study offers a valuable new option for those afflicted year after year by winter depression."