Atypical depression is a subtype of major depression or dysthymic disorder that involves several specific symptoms, including increased appetite or weight gain, sleepiness or excessive sleep, marked fatigue or weakness, moods that are strongly reactive to environmental circumstances, and feeling extremely sensitive to rejection.
What is atypical depression?
Atypical depression can be a "specifier" for either major depression or dysthymic disorder. People with atypical depression have often experienced depression first at an early age, during their teenage years.
A person with classic major depression has at least five of the following nine symptoms:
- Sadness or depressed mood most of the day or almost every day
- Loss of enjoyment in things that were once pleasurable
- Major change in weight (gain or loss of more than 5% of weight within a month) or appetite
- Insomnia or excessive sleep almost every day
- A state of physical restlessness or being rundown that is noticeable by others
- Fatigue or loss of energy almost every day
- Feelings of hopelessness or worthlessness or excessive guilt almost every day
- Problems with concentration or making decisions almost every day
- Recurring thoughts of death or suicide, suicide plan, or suicide attempt
Dysthymic disorder, now known in the psychiatric community as "persistent depressive disorder," is a condition involving the presence of a depressed mood more days than not for at least a two year period in adults (one year in children and adolescents) plus at least two of the above associated symptoms, but fewer than the five symptoms which define a major depressive episode.
Despite its name, atypical depression is very common. It is contrasted with "melancholic" depression, another subtype of depression, involving symptoms of insomnia (rather than oversleeping), loss of appetite (rather than increased appetite), a relative lack of mood reactiveness to environmental circumstances, and a markedly diminished ability to feel pleasure.
What are the symptoms of atypical depression?
The main characteristic of atypical depression that distinguishes it from melancholic depression is mood reactivity. In other words, the person with atypical depression will see his or her mood improve if something positive happens. In melancholic depression, positive changes will seldom bring on a change in mood. In addition, diagnostic criteria call for at least two of the following symptoms to accompany the mood reactivity:
- Sleeping too much (hypersomnia)
- Increased appetite or weight gain
- Having a more intense reaction or increased sensitivity to rejection, resulting in problems with social and work relationships
- Having a feeling of being weighed down, paralyzed, or "leaden"
A doctor will investigate physical causes for any of these symptoms. That will include a physical exam and tests to look for a problem such as hypothyroidism. With hypothyroidism, having low levels of thyroid hormone can lead to symptoms that include depression and weight gain.
What causes atypical depression?
Depression is believed to be the result of impaired functioning of brain circuits that regulate mood, and that allow one region of the brain to communicate with another. Nerve cells contained within these circuits transmit signals through brain chemicals called neurotransmitters -- such as dopamine, serotonin, and norepinephrine. Antidepressant medicines are thought to "tweak" these chemicals and thereby improve the efficiency of brain circuits related to mood.
While the exact cause of depression is unknown, there are risk factors for depression, including:
- A family history of depression
- A significant loss -- from death, divorce, or separation -- that may trigger an underlying vulnerability to depression (rather than simply normal grief)
- Interpersonal conflicts and related emotions such as guilt
- Any type of abuse -- physical, sexual, or emotional
- Any type of major life event such as moving, changing or losing a job, graduating, retiring, or social isolation in people who have a biological vulnerability to depression
- Any type of serious illness such as cancer, heart disease, stroke, or HIV
- Drug or alcohol abuse
How is atypical depression treated?
Doctors are likely to recommend psychotherapy (talk therapy) and/or medications for atypical depression, depending on the severity of the symptoms. There are different types of psychotherapy and medications available for treatment. You may be referred to a specialist such as a psychiatrist, psychologist, or other licensed mental health professional for care.