Shifting Seasons and Shifting Moods
Winter is here and with the change of the season comes an unwelcome shift in mood for almost 10% of the population in some regions of the country. Seasonal Affective Disorder (SAD) is considered a type of major depressive disorder, according to the American Psychiatric Association.
Although most people who meet the criteria for SAD experience symptoms in the winter, there are some who have SAD other times of the year. Those who experience SAD in the summer months report increased anxiety as a symptom. Another lesser know fact about SAD is that some people experience BiPolar (symptoms of depression and mania or hypomania) episodes during the seasonal mood changes, rather than just depression.
What is SAD?
SAD is diagnosed when a pattern of depressive or BiPolar symptoms are present consistently during the same season. In order to meet the criteria for SAD, the mood changes must remit during other times of the year. The actual diagnosis changed from Seasonal Affective Disorder to Major Depressive Disorder with Seasonal Patterns with the publication of the DSM-4, Diagnostic and Statistical Manual of Mental Disorders.
The criteria for diagnosis are the same as for Major Depressive Disorder or BiPolar Disorder. The only difference is that the symptoms occur at specific times of the year and remit when the season changes again. ‘Winter Blues’ is a less severe form of seasonal depression that does not meet the full criteria of a mood disorder.
Dr. Norman Rosenthal is a retired expert from the National Institutes of Mental Health whose field of study is cyclical mood disorders. He described people who suffer from SAD in an interview with Psychiatry, a peer reviewed journal of evidence-based information. Dr. Rosenthal says that people with SAD begin to slow down as the days become short and dark. Their energy level decreases, they tend to eat more – especially sweets and starches – and gain weight during the winter months. Their relationships suffer, as they tend to withdraw from friends and family.
Rosenthal says that people with SAD have trouble concentrating, so often their work suffers. They can become quite depressed over the winter months, with symptoms lasting four or five months until the days become longer again. He also points out that SAD is linked to lack of sunlight, so people with this disorder may become depressed on cloudy days at any time of year, or if they re in dark, windowless offices, basements or apartments. Some people with SAD report an increase in sleep of up to 2.5 hours over the winter months or on cloudy days.
What Causes SAD?
Some researchers believe that SAD is an evolutionary adaptation of winter hibernation. The two brain chemicals, Melatonin and Serotonin, are believed to be involved in the process. Melatonin is released by the pineal gland when it gets dark; this regulates our sleep cycles and many of the biological processes that take place while we sleep. Serotonin, a neurotransmitter that is linked to depression, is also suppressed in the winter. There is some evidence that light received through the retina triggers a release of serotonin.
The evolutionary adaptation theory suggests that these two chemical processes are responsible for helping animals survive the seasonal changes. Based on that theory, the presence of SAD in humans may be connected to those seasonal biological responses. Theoretically, low mood requires less energy, and energy conservation is important for survival in our animal ancestors.
What Can You Do About SAD?
Treatment for SAD varies depending on the severity of the symptoms. Some people find relief from mild symptoms (Winter Blues) by simply sitting outside in the sunlight for 20 minutes or more daily during the winter months. Those with clinical symptoms of SAD often find bright light therapy to be most helpful. People who choose bright light therapy need to be aware of the specifics about dosage and timing.
Best practices for light therapy are largely based on research out of Columbia University Center for Light Treatment and Biological Rhythms. According to their research, people with SAD had the best responses to bright light therapy for 30 minutes (or more as needed) upon awakening. Bright light therapy requires 10,000 LUX from a ‘sunshine simulator’ aka full spectrum lighting.
This is an important distinction, as most of the less expensive and more popular light boxes or gadgets that are sold in department stores do not provide the recommended therapeutic dose. Another important fact that is not usually publicized is that the light bulbs/tubes need to be changed every 1-2 years. While the bulbs/tubes may last for over a decade, they lose strength with regular use after a year.
Dawn simulation is another form of light therapy that has been found helpful for many. Dawn simulation requires that one uses a light simulator in lieu of an alarm clock to increase the amount of light in the bedroom in the early morning hours. Some people find this is more convenient than sitting in front of a light box for 30-60 minutes upon rising. Others reported that it disrupted their sleep partner’s normal sleep pattern.
Negative air ionization is being studied as a treatment for SAD, but is still considered experimental at this time. Negative air ionization mimics summer-like conditions by supplementing the sparse winter ion supply. While some air filters use negative ionization, most do not deliver a therapeutic dose.
Light therapy has also been found useful in managing ADHD and related attention and concentration/distraction problems. As a person with ADHD and SAD, I have found that bright light therapy for SAD with the 10,000 LUX light box is most effective when started in late-September and used until May or June, depending on where you live.
To help manage my ADHD symptoms, I also use a 5000 LUX full spectrum light as a desktop lamp throughout the day. I use this year round to help with ADHD symptoms. In my personal experience, both of these non-medication treatments have been effective when used consistently.
Those who do not respond to light therapy may be prescribed anti-depressants, cognitive-behavioral therapy and/or natural supplements. An evaluation by a psychiatrist or medical provider who is knowledgeable in mental health conditions is recommended to determine the right treatment regimen for your specific symptoms.
"Center for Light Treatment and Biological Rhythms." Light Treatment Center. Columbia University Medical Center. Web. 22 Oct. 2013.
"Seasonal Affective Disorder." Credo Reference: Where Are You From? Columbia University. Web. 22 Oct. 2013.
Targum, Steven, MD, and Norman Rosenthal, MD. "Seasonal Affective Disorder." Psychiatry (Edgmont) 5.5 (2008): 31-33. National Center for Biotechnology Information. U.S. National Library of Medicine. Web. 22 Oct. 2013.