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- affective disorder
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seasonal affective disorder
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What is seasonal affective disorder (SAD)?
Seasonal affective disorder (SAD) is a mood disorder featuring recurring depression in autumn and winter, with nondepressive periods in spring and summer. It was first described in 1984 by American psychiatrist Norman Rosenthal.
Those with SAD may experience difficulty waking up, oversleeping, overeating, weight gain, fatigue, difficulty concentrating, and withdrawal from social activities. They may also feel depressed, pessimistic, and unable to enjoy usual pleasures.
SAD is more common in regions far from the Equator and affects an estimated 5 percent of people in the United States and 4 to 14 percent in Europe, depending on latitude. Lack of light, biological vulnerability, and stress can predispose an individual to SAD.
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When does seasonal affective disorder usually occur?
Seasonal affective disorder (SAD) is a mood disorder featuring recurring depression in autumn and winter, separated by nondepressed periods in spring and summer. SAD is estimated to affect approximately 5 percent of people in the United States and between 4 and 14 percent of people in Europe, and it is less common in China and Japan.
In autumn, as days shorten, those with SAD may experience difficulty waking up, oversleeping, overeating, and weight gain, as well as fatigue and decreased energy. Light therapy, exercise, antidepressant medications, and cognitive behavior therapy are all potential treatments for SAD.
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What are common symptoms of seasonal affective disorder?
Seasonal affective disorder (SAD) is a mood disorder featuring recurring depression in autumn and winter, separated by nondepressed periods in spring and summer.
SAD symptoms generally include difficulty waking up, oversleeping, overeating, and weight gain. Those affected may crave carbohydrate-rich foods, such as sweets and breads, and experience fatigue and decreased energy, especially in the afternoon. Difficulty concentrating, trouble completing tasks, and withdrawal from friends, family, and social activities may also occur. People with SAD may also experience higher levels of depression.
Bright light exposure, called light therapy, is a primary treatment for SAD.
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Why might some people experience SAD during specific seasons?
Seasonal affective disorder (SAD) is a mood disorder featuring recurring depression in autumn and winter, with nondepressive periods in spring and summer. Shortening days that lead to more hours of darkness can cause atypical depressive symptoms in people susceptible to SAD. These symptoms include oversleeping, overeating, fatigue, difficulty concentrating, and social withdrawal.
Other factors that can predispose someone to SAD include stress and biological vulnerability. Levels of melatonin and the neurotransmitter serotonin fluctuate across the seasons and affect circadian rhythms. Shifts in circadian rhythms can lead to stress, which can elicit symptoms in vulnerable people.
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How can seasonal affective disorder affect daily life and mood?
Seasonal affective disorder (SAD) is a mood disorder featuring recurring depression in autumn and winter, separated by nondepressed periods in spring and summer. SAD can impact daily life and mood, causing difficulty waking up, oversleeping, overeating, and weight gain. People with SAD may experience fatigue and decreased energy, struggle with concentration, and withdraw from social activities. They may also become depressed, pessimistic, and unable to enjoy typical pleasures.
SAD sufferers cannot completely avoid severe anxiety-provoking situations, which can lead to alcohol abuse, higher levels of depression, and suicidal thoughts. Light therapy, exercise, antidepressant medications, and cognitive behavior therapy can alleviate symptoms.
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What are some ways to treat or manage seasonal affective disorder?
Seasonal affective disorder (SAD) is a mood disorder featuring recurring depression in autumn and winter, separated by nondepressed periods in spring and summer.
SAD symptoms include difficulty waking, oversleeping, overeating, weight gain, cravings for carbohydrates, fatigue, difficulty concentrating, and withdrawal from social activities. People with SAD may experience major depression in winter and normal mood in spring/summer, or bipolar disorder, with depression in winter and hypomania or mania in spring/summer.
Treatments for SAD include light therapy, which involves exposure to bright light, usually from a light box. Other treatments are exercise in a brightly lit setting, antidepressant medications, and cognitive behavior therapy. Starting treatments early in autumn may prevent the development of winter symptoms.
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seasonal affective disorder (SAD), mood disorder characterized by recurring depression in autumn and winter, separated by periods of nondepression in spring and summer. The condition was first described in 1984 by American psychiatrist Norman Rosenthal.
In autumn, when the days grow progressively shorter, resulting in an increase in the number of hours spent in darkness, people susceptible to SAD develop atypical depressive symptoms. These symptoms generally include difficulty waking up in the morning; a tendency to oversleep, to overeat, and to gain weight; a craving for carbohydrate-rich foods, such as sweets and breads; fatigue and decreased energy, especially in the afternoon hours; difficulty concentrating and accomplishing tasks; and withdrawal from friends, family, and social activities. Along with this predictable cluster of symptoms, people with SAD also become depressed, pessimistic, and unable to enjoy the things that usually give them pleasure.
When spring comes, these symptoms generally resolve, and people with SAD feel well again. In fact, some people with SAD become euphoric during the summer. They may experience a condition known as hypomania, in which they have rapid thoughts and speech, have grandiose ideas about themselves, or become short-tempered, irritable, and impulsive. If these symptoms become severe, affected individuals may show bad judgment and behave recklessly—characteristics of a condition described as mania. People with SAD may suffer from recurring major depressive disorder, with severe depression in winter and normal mood in spring and summer, or from bipolar disorder, with depression in winter and hypomania or mania in spring and summer. Variants of SAD include a milder form, commonly known as the “winter blues,” and a condition of chronic depression with winter exacerbations. There is also a condition of regular summer depressions, called reverse SAD (or summer SAD), which is less common and less well understood than the winter variety.
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The condition is a common illness in regions distant from the Equator, which experience dramatic shifts in length of daylight between summer and winter. SAD is estimated to affect approximately 5 percent of people in the United States and between 4 and 14 percent of people in Europe, depending on latitude. The condition is far less common in China and Japan. Women are more likely than men to develop SAD, especially during their reproductive years. This suggests that female sex hormones may play a role in sensitizing the brain to changes in environmental light. Children and adolescents also may be affected.
In addition to lack of light, other factors that predispose an individual to SAD include biological vulnerability (e.g., being female) and stress. Levels of the hormone melatonin and the brain neurotransmitter serotonin vary across the seasons and affect circadian rhythm. Shifts in circadian rhythms can lead to stress, which is frequently associated with waking up early in the morning. Stress from the demands associated with managing a family and with work can elicit symptoms in vulnerable people. In addition, SAD tends to occur in individuals who have an affected family member, and several genes have been identified that may contribute to the development of the condition. However, more research is needed to understand the genetic link to SAD.
The primary treatment for SAD is light therapy, which involves exposing the affected person to bright light, usually from a fixture called a light box. Fluorescent light tubes placed behind a screen that filters out potentially harmful ultraviolet rays are commonly used. Fixtures using light-emitting diodes also may be effective, though they have not been tested extensively. The duration of light therapy required depends on the individual, the geographical region, and the time of year. Mornings are usually the best time for light therapy, though it may provide beneficial effects at any time of the day. Other treatments include exercise, especially in a brightly illuminated setting, antidepressant medications such as bupropion, and cognitive behaviour therapy. Treatments started early in autumn may prevent the development of winter symptoms in susceptible individuals.