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Seasonal Affective Disorder: More Than Just the ‘Winter Blues’

Leading SAD experts provide a valuable overview of this potentially debilitating condition

For some people, the onset of fall and winter leads to a possibly serious condition called seasonal affective disorder (SAD). In an interview with Keep in Touch, George C. Brainard, PhD, a Thomas Jefferson University neurology professor and leading SAD researcher, and Brenda Byrne, PhD, director of the Seasonal Affective Disorder Program at Jefferson, explain what women need to know.

Keep in Touch: How common is SAD among women?

Dr. Brainard: In terms of diagnosis, SAD is very common among women. Depending on the epidemiological study you look at, about 60 to 70 percent of people diagnosed are women.

Dr. Byrne: Those figures match the experience we have at Jefferson, as well as the national and international picture.

KIT: What causes SAD?

Dr. Brainard: We don’t know exactly, but recently, scientists have discovered that the human eye houses two completely different sensory systems. One allows us to see, while the other stimulates biological and behavioral changes. So, the eye plays a role in regulating daily rhythms and hormones at a subconscious level. To put it another way, we now know that our eyes are like our ears, which help us hear but also keep us oriented relative to gravity. This discovery may have important implications in understanding and treating SAD.

KIT: In the meantime, what are signs and symptoms of SAD that women should watch for in themselves and in their loved ones?

Dr. Brainard: It’s important to first understand that there are many types of depression. Fall and winter depression, or SAD syndrome, has commonalities with all types of depression. Some of those commonalities include feelings of sadness and hopelessness, suicidal thoughts or brooding on death, low self-esteem, guilt, physical fatigue and weakness, diminished ability to concentrate and diminished libido.

In addition to those signs and symptoms that can be present in all forms of depression, there are also some characteristics that distinguish seasonal depression. For starters, typical depression is not specific to a time of year, whereas SAD syndrome is clearly linked to the change in season. Also, while general depression can sometimes be linked to an event or anniversary of some kind, SAD is generally free of such ties.

Dr. Byrne: Another significant difference is impact on appetite. Often, people with non-seasonal depression lose their appetites. With SAD, patients are often driven to eat high-sugar, high-carbohydrate foods. Consequently, they will gain weight. In fact, some of our patients gain between 10 and 30 pounds during the fall and winter months. This pattern has been compared to the behavior of hibernating animals that forage and put on a lot of weight and then withdraw during the fall and winter.

The notion of hibernation comes into play with sleep patterns, as well. While garden-variety depression often leads to insomnia, SAD is marked by increased sleepiness. During spring and summer, some of our SAD patients can function just fine on seven or eight hours of sleep. But once fall and winter come, they need 10, 12 or even 14 hours a night! And in many cases, they believe that they could sleep all day if their families and jobs permitted it.

KIT: It would seem that many people change their habits slightly as the weather cools off and the days get shorter. Isn’t it somewhat normal to eat and sleep a bit more?

Dr. Brainard: There is a phenomenon known as sub-clinical SAD, in which people do put on a few pounds or need a little more sleep. Informally, this is known as “cabin fever” or “winter blues,” and the studies suggest that as much as 20 percent of the population experiences sub-clinical SAD. For these people, the change in seasons isn’t deeply debilitating and usually doesn’t have major effects on their lives or their families.

Dr. Byrne: However, about one to three percent of people in the Philadelphia latitude experience clinical SAD. Those who do hit a level of clinical depression really need professional intervention. If you suspect that you or someone you care about has SAD, see someone who’s trained in diagnosing this disorder and who can guide you through therapy.

KIT: How is SAD treated?

Dr. Brainard: Both clinical and sub-clinical SAD have been shown to be responsive to light therapy. If you’re experiencing clinical SAD, you should definitely work with a professional to have your condition diagnosed and treated. If you have sub-clinical SAD – in other words, you’re just “dragging” – you may be able to attempt some therapy on your own. But by working with a professional, you’ll probably achieve much better results.

Dr. Byrne: To be sure, light therapy is the primary form of therapy and our first choice at Jefferson for treating SAD. The good news about light therapy is that it generally works very quickly and its side effects, if any, are easily managed. Patients who initiate this therapy often see some change in three or four days, and very robust changes within two weeks or so.

Of course, medication is another option for patients who, for whatever reason, are unable or unwilling to do light therapy. Medication can often take longer to bring positive change, and can also pose some side effects.

Another treatment option is cognitive behavioral therapy. In one clinical trial, that has been shown to be effective in treating SAD, and especially effective when combined with light treatment.

KIT: In closing, Dr. Brainard and Dr. Byrne, what are the most important things for Keep in Touch readers to know and understand about SAD?

Dr. Byrne: It’s important for readers to understand that SAD is a very real condition, and if you are experiencing the signs and symptoms, you owe it to yourself to seek help. Keep in mind, the classic SAD patient is a high-energy, high-functioning person during the spring and summer months. So if you feel “not yourself” in fall and winter, SAD could be the reason – and there are ways to help.

Dr. Brainard: I also think our readers should be aware of the depth and breadth of experience the team at Thomas Jefferson University and Thomas Jefferson University Hospital offers for this condition. We’ve maintained a center dedicated to this disorder for over two decades, we’re active in the Society for Light Treatment and Biological Rhythms, and we continue to be involved in cutting-edge research that will help further enhance treatment for SAD. All of that yields real benefits for Jefferson patients.

Make an appointment with a Jefferson physician online or by calling 1-800-JEFF-NOW.