Before we discuss the diagnosis and treatment of SAD, I feel like it’s important to say something about the unfortunate stigma that depression, and mental health in general, has earned in our society. Depression is a disease. Period. Telling someone who struggles with depression to simply “snap out of it” is like telling someone with diabetes to just “suck it up”. You would never tell that individual with diabetes that it isn't “normal” for them to need medication on a daily basis. Why then do we hold those who battle mental illness to a different standard? We need to reject the “us versus them” mentality. Published studies report the lifetime incidence of SAD in the US as high as 10%. In my professional experience, those numbers are even higher. We are them. They are us.
In the evaluation of a patient complaining of seasonal depressive symptoms, my first step is to conduct a focused but thorough interview to determine onset of symptoms, duration, severity, aggravating and alleviating factors, as well as past attempts at treatment. I’m also very interested in family history as there appears to be a strong familial component. I also make use of clinical screening tools to be more objective about the patient's experiences. It's also important to rule out metabolic disorders that could be mimicking true depression. These include conditions such as hypothyroidism, anemia, hypercalcemia, insomnia, and metabolic syndrome X among others.
Once a diagnosis is made, we can start working toward a solution. Many patients are reluctant to start medication. While I do believe medication to be an important piece of an individualized treatment plan, it is not necessarily the most important piece or even the most effective. I am a strong proponent of CBT or cognitive behavioral therapy. Studies have consistently shown that CBT is as effective as medication (if not more so). It also appears more likely to prevent a relapse. The best results, however, are seen by those who combine both medication and CBT.
In the case of SAD specifically, light therapy is a very useful first line treatment. Even though effects were modest in clinical trials, the concept makes sense--treat a lack of light with a prescription for light. While I would always advocate spending as much times outdoors as possible, it’s not always reasonable to expect patients to spend large amounts of time outside especially during the winter. Balancing the risks of excessive sun exposure is another concern.
But what exactly does light do for our brains? For starters, it’s what drives our sleep-wake cycle known as the circadian rhythm. Light suppresses melatonin production allowing us feel more awake and alert. Exposure to light is also believed to increase levels of serotonin in the brain, the same desired effect of common drugs such as Paxil and Prozac.
The best research available recommends a specific type of light box. First of all, it should produce broad spectrum white light. Blue light simply hasn’t been studied enough to replace the more common white lights.The box be capable of producing 10,000 lux and needs to be placed within 30” of the face. Best results are obtained by looking into the box at angle or head on versus keeping your head down (while reading, for example). The recommended duration of treatment is 20-30 minutes per day. But is that safe you ask? Most light boxes emit very little UV radiation and have not been show to damage the eyes.
For those persons suffering from SAD, I also tend to recommend Vitamin D supplementation. In south central Idaho where I practice, the majority of the population is D deficient, largely due to our northern latitude. There seems to be a correlation between Vitamin D and a wide array of disorders. While it may be anecdotal, my patients that supplement Vitamin D usually show significant improvements in energy levels and mood. I recommend 2,000 IU daily in this area. We will occasionally treat those that are severely deficient with megadoses the first few weeks and then back down to a lower daily dose. Some patients choose to supplement only during the winter months.
If you suspect that you or a loved one could be suffering from seasonal affective disorder, get in touch with your doctor or PA. Talk to them about light therapy, counseling, and/or medication. There is hope and it could mean the difference between happy holidays and the winter blues.