What is Seasonal Affective Disorder?
Some people suffer from symptoms of depression during the winter
months, with symptoms subsiding during the spring and summer months.
This may be a sign of Seasonal Affective Disorder (SAD). SAD is a mood
disorder associated with depression episodes and related to seasonal
variations of light.
SAD was first noted before 1845, but
was not officially named until the early 1980's. For centuries,
sunlight has peaked and ebbed throughout the year, affecting the
seasonal activities of animals (i.e., reproductive cycles and
hibernation). SAD may be an effect of this seasonal light variation in
humans. As seasons change, there is a shift in our "biological
internal clocks" or circadian rhythm, due partly to these changes in
sunlight patterns. This can cause our biological clocks to be out of
"step" with our daily schedules. The most difficult months for SAD
sufferers are January and February, and younger persons and women are
at higher risk.
Symptoms Include:
- regularly occurring symptoms of
depression (excessive eating and sleeping, weight gain) during the
fall or winter months.
- full remission from depression occur
in the spring and summer months.
- symptoms have occurred in the past
two years, with no non-seasonal depression episodes.
- seasonal episodes substantially
outnumber non-seasonal depression episodes.
- a craving for sugary and/or starchy
foods.
Possible Cause of this Disorder
Melatonin, a sleep-related hormone secreted by the pineal gland in
the brain, has been linked to SAD. This hormone, which may cause
symptoms of depression, is produced at increased levels in the dark.
Therefore, when the days are shorter and darker the production of this
hormone increases.
Treatments
Phototherapy or bright light therapy has been shown to suppress
the brain's secretion of melatonin. Although, there have been no
research findings to definitely link this therapy with an
antidepressant effect, many people respond to this treatment. The
device most often used today is a bank of white fluorescent lights on
a metal reflector and shield with a plastic screen. For mild symptoms,
spending time outdoors during the day or arranging homes and
workplaces to receive more sunlight may be helpful. One study found
that an hour's walk in winter sunlight was as effective as two and a
half hours under bright artificial light.
If phototherapy doesn't work, an
antidepressant drug may prove effective in reducing or eliminating SAD
symptoms, but there may be unwanted side effects to consider. Discuss
your symptoms thoroughly with your family doctor and/or mental health
professional.
Source: National Mental Health
Association
