Dr. Kelly Rohan’s study of Seasonal Affective Disorder (SAD) treatment shows that Cognitive-Behavioral Therapy (CBT) – not light therapy – may best prevent recurring symptoms of seasonal depression.
10,000 lux light therapy has received a great deal of attention as an effective treatment for people who find themselves in a clinical depression each fall due to changing light and later sunrise. But can any therapy prevent the recurrence of winter depression each year?
Dr. Kelly Rohan was determined to answer that question. She conducted the first study to ever examine whether treatments for Seasonal Affective Disorder (SAD) such as 10,000 lux light therapy or cognitive behavioral therapy for SAD (CBT) administered in one winter, could prevent a recurrence of winter depression symptoms in the following year.
Dr. Rohan corresponded with this author about her SAD study.
Dr. Kelly Rohan Looks at Cognitive-Behavioral Therapy (CBT) for SAD vs. Light Therapy
LD: Would you conclude from your study of SAD treatment that it’s better for people to seek CBT for SAD without using light therapy at all when they have been diagnosed with Seasonal Affective Disorder?
KR: “Yes, I do conclude that it is better for people to [seek] CBT (without light therapy) in the initial treatment phase because they will be better off in the next winter.”
A Look at Dr. Rohan’s SAD Treatment Research Findings
LD: Your study compared three treatments for seasonal affective disorder:
- one group had cognitive therapy (CBT) only;
- a second group had CBT plus light therapy;
- and the third group had solo light therapy, i.e. light therapy only, without any form of talk therapy.
You found that in the following winter, the two CBT groups only had a 5.5 to 7% recurrence of depression, but in the group that received only light therapy the first year, almost 37% had a recurrence of seasonal depression the following winter?
KR: “This is correct. … the difference between the CBT groups (alone and in combination with light) and the light therapy alone group are statistically significant, large, and clinically meaningful.”
CBT Alone May Better than Light Therapy for Preventing Future Depressive Symptoms
LD: But there was another very important finding in your SAD treatment study when you interviewed even the people who did not develop major depression the following year.
KR: “Continuous depression scores were measured in all participants [the next winter.] This was an important thing to do because not having a recurrence does not mean that you are totally symptom-free.”
LD: And you found that only the people who were treated with CBT alone, without light therapy, had fewer and less severe depressive symptoms the following year?
KR: “Yes…The findings as a whole…suggest that initial treatment with solo CBT has better outcomes than initial treatment with solo light therapy in the next winter, but that initial treatment with combined CBT/light therapy does not generally [show this benefit.]”
Dr. Kelly Rohan has received a grant from the National Institute of Mental Health (NIMH) and is continuing to explore the question of how to prevent Seasonal Affect Disorder from recurring each year.
As of December 2009, Rohan’s study revealed that people who receive cognitive-behavioral therapy for SAD had fewer recurrences of major depression and less severe SAD depressive symptoms the year after treatment than those who have light therapy and no talk therapy. Those who receive light therapy in combination with CBT had less recurrence of major depression but did not get the relief from remaining depressive symptoms, that those in the solo CBT group achieved.
©Lisa C. DeLuca, all rights reserved. It is a violation of copyright law to reproduce this work on the web or for business use without permission from the author. This article was originally published on the web in on December 17th, 2009. Please contact the author with your reprint request.
This article is for general information only and is not a substitute for personal medical or mental health advice. If you are experiencing troubling symptoms please seek the advice of a medical or mental health professional in person.