Talk therapy more effective long term treatment for SAD than light therapy, study finds
(30 October 2005: VIDYYA MEDICAL NEWS SERVICE) -- The daily routines of one in ten American in Vermont, Alaska, Maine and other northern states will change for the worse on Oct. 30.
The alterations start every year around October just after the end of daylight savings time. For most, the clock shift just adds an hour to the weekend -- but for sufferers of seasonal affective disorder, a syndrome involving recurring bouts of depression during fall and winter months, it marks the beginning of a difficult time of year when many forgo an after-work run for a nap, watch television instead of walk the dog, or sleep later in the morning.
With this year's turning back of the clock, the 14.5 million Americans susceptible to SAD may begin feeling fatigued, worthless, disinterested, even suicidal.
Many will receive treatment involving sitting in front of a light box for an hour or two a day in hopes that the white fluorescent or full-spectrum light will simulate sunlight and make them feel better.
The treatment works reasonably well but is hard to stick with, so Kelly Rohan, a SAD expert and assistant professor of psychology at the University of Vermont, views it as more a quick fix than long-term solution.
She is currently exploring treatment through cognitive-behavioral therapy, a commonly used form of "talk therapy" that has been used for non-seasonal depression since the 1960s, with SAD patients.
She thinks this is the first time this type of therapy has been deployed to treat SAD, and the results in early research and clinical trials are promising.
In a 2005 study involving 61 patients, Rohan treated one group with daily light therapy, another with 12 sessions of CBT and a third group with a combination of both treatments. A less popular option -- selective serotonin reuptake inhibitors -- wasn't used.
Rohan's findings, which will be published later this year as a follow-up to a 2004 study that appeared in the June issue of Journal of Affective Disorders, show that all three groups showed comparable improvement across the six weeks of study treatment compared to a wait-list control group.
In addition, the largest percentage of patients (80 percent) responded in full when CBT and light therapy were combined. Furthermore, those who underwent CBT -- both alone and with light therapy -- were less depressed at the one-year follow-up compared to patients who had been treated with light therapy alone.
Only six percent of the CBT participants met the criteria for depression at the one-year follow-up, while 40 percent of light-exclusive participants met the depression criteria during the winter season of the next year.
The majority of light therapy users reported having a hard time adhering to the recommended twice-daily 45-minute light box sessions at the end of six weeks of study treatment.
Rohan's research offers compelling evidence that CBT talk therapy by itself may be an effective treatment for SAD and may offer some long-term benefits over light therapy.
"Sitting in front of a light box every day of the fall and winter promotes sedentary behavior and is hard for people to maintain over time," she says.
"Cognitive-behavioral therapy is a time-limited treatment and appears to have better long-term effects."
The cause of SAD, first noted as far back as 1845 but officially named in the 1980s, has been attributed to a biochemical imbalance in the hypothalamus due to the shortening of daylight hours and the lack of sunlight in winter. The theory goes that as seasons change there is a shift in people's "biological internal clocks" or circadian rhythm, due in part to changes in sunlight patterns.
Because of this, incidence of SAD varies by locale, with rates ranging from one percent in Florida to 10 percent in Vermont, Alaska and Orono, Maine, where Rohan first became interested in SAD while working on her doctorate in clinical psychology.
The condition ranges in intensity from not being able to function normally without continuous medical treatment to a mildly debilitating case of "winter blues."
It seemed to Rohan, who came to UVM earlier this fall after spending five years as an assistant professor of medical and clinical psychology at the Uniformed Services University of the Health Sciences, that cognitive-behavioral therapy was an obvious way to treat SAD, despite it never being used before.
"As far as I know we're the first group to apply it to SAD," she says. "Some people would argue that SAD is a purely biological kind of depression, so any type of psychological treatment such as CBT shouldn't work, but it does. I think it's good news that there appears to be more than one way to intervene and improve winter depression."
During the therapy, which occurs twice a week for six weeks, Rohan teaches patients about the origins of SAD and how learned behaviors and ingrained negative thought patterns contribute to their symptoms.
She also encourages patients to act more like they do in the summer and continue regular activity. She says it doesn't necessarily have to be an outdoor activity like skiing, just something that keeps people active and engaged during the fall and winter months.
One SAD patient was an artist, for example, who tended not to have time in the summer to work on her art. "We started having her do more art in the winter. It gave her something to look forward to," Rohan says. "The key is to limit hibernating and develop some winter interests."
Disproving light therapy as a form of treatment isn't Rohan's goal. Instead she hopes to show its shortcomings and offer an alternative that is easier to comply with in the long run, has more lasting effects and teaches lifelong coping skills.
"Before investing in a light box, I encourage SAD patients to go for a 30-minute walk after sunrise every morning. This gets just as much light to the retina as using light therapy and has the added benefit of increasing physical activity," she says.
"The time change is a bear; just the thought of winter can be enough to trigger symptoms. We encourage people to do whatever it is they get enjoyment out of and to recognize the symptoms early so they can deal with them before they become unmanageable."
Return to Vidyya Medical News Service for 30 October 2005