Sunlight and seasonal changes have a great impact on human behavior. Seasonal Affective Disorder (SAD) is a form of depression -- sometimes called the winter blues -- that follows a seasonal pattern and occurs at the same time every year without any significant related stressors. Affected people are symptom-free during spring and summer and have recurrence of depression during the following fall and winter.
January and February seem to be the most difficult months for these people. Onset is typically seen from September to November with complaints of excessive tiredness and fatigue, increased sleepiness and often a desire to sleep for long periods, increased appetite and craving for carbohydrates, especially cookies and bread. These symptoms are often associated with the decrease in the amount of sunlight.
The specific cause of SAD remains unknown. Research has shown that the prevalence of SAD is more frequent with increasing distance from the equator. People who live in the tropics don’t seem to have this cyclical pattern of mood disturbance. Almost one-third of people with SAD describe their symptoms originating from their childhood years.
It is estimated that 25 percent of people in the northern latitudes of the United States experience some form of SAD. Female gender, northern latitudes and having a family history of mood disorder like depression or bipolar disorder increases the risk of having SAD. A comprehensive clinical evaluation with longitudinal life history is essential for accurate diagnosis.
It is likely many factors contribute to SAD. Research suggests the possibility of a dysfunction in the biological clock or the circadian rhythm. The reduced level of natural light may disrupt the body’s internal clock, leading to mood changes. Melatonin, a natural hormone secreted by the pineal glands in the brain, may be influenced by the seasonal change leading to disruption of the delicate control of the sleep-wake cycle. Recent studies have implicated serotonin level fluctuation as a possible cause. Several genes also have been suggested to play a role especially in familial cases.
The most common symptoms of SAD are:
• Depression that begins in fall / winter and goes away in summer.
• Oversleeping or Hypersomnia.
• Appetite change -- especially increased appetite and carbohydrate craving.
• Weight gain.
• Difficulty focusing or concentrating.
• School problems, declining grades.
• Loss of energy and interest in pleasurable activities.
• Potential substance abuse -- especially with alcohol -- and thoughts of suicide in severe cases.
The general treatment for Seasonal Affective Disorder may include light therapy, medications, psychotherapy -- cognitive behavioral therapy, sleep deprivation, aerobic exercise and outdoor recreation.
Light Therapy: Also known as phototherapy, light therapy is one of the most effective treatments. This can be used at home, work place, during travel or in a clinic or hospital. Exposure to sunlight is the best and cheapest option, if available. Simple steps like a morning walk or activities near a window with morning sun, clearing the area surrounding to increase the lighting at home or office may be sufficient to treat SAD in some people. When sun light is not possible, artificial bright light therapy can be used. This should be initiated under the supervision of a trained physician like a sleep specialist or a psychiatrist who has expertise in the area.
Medication: The FDA has approved the antidepressant bupropion (Wellbutrin-XL) for the prevention of depressive symptoms in patients with SAD. Other antidepressants like sertaline (Zoloft), fluoxetine (Prozac), venlafaxine (Effexor) have shown promise. Several newer medications targeting melatonin receptors and serotonin also have shown promise. Talk to your doctor to explore these options.
Psychotherapy: Recent studies have shown that cognitive behavioral therapy may have a significant impact in the treatment of SAD. Targeting the negative thoughts and improving coping skills have been successful in helped patients with SAD. Good sleep hygiene practices and a structured environment may help to decrease the severity and frequency of symptoms.
Lifestyle modification: Simply making your environment brighter and sunnier may help. Regular physical exercise, increased social interaction and outdoor activities may be sufficient improve your mood. If the symptoms are severe, consultation with a SAD specialist is advised.
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