Major depression is a common and serious medical illness affecting more than 13 million Americans, or approximately 6.6 percent of the population in a given year. Unlike normal temporary emotional states of sadness from external events like a loss or other negative events, major depression is persistent and can significantly interfere with an individual's thoughts, behavior, mood, and physical health. Mental illness is the leading cause of disability in the U.S. and depression is the most predominant illness within the mental health arena.

Women are almost twice as likely as men to suffer from depression. However, some experts feel that depression in men is significantly under-reported. Major depression can occur at any age, including childhood, the teenage years and adulthood. Major depression has no racial, ethnic, or socioeconomic boundaries. About two-thirds of those who experience an episode of depression will have at least one other episode in their lives. It is not unusual for depression sufferers to have more than one episode in any given year.

Major depression, also known as unipolar depression, is only one type of depressive disorder. Other depressive disorders include dysthymia (a type of chronic depression) and bipolar depression (the depressed phase of bipolar disorder or manic depression). Individuals suffering from bipolar disorder experience both depression and mania in a cyclical fashion. Mania often involves abnormally and persistently elevated mood or irritability, elevated activity and self-esteem levels and excessive talking.

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Scientists have not yet determined the root cause of major depression. However, there is strong evidence there may be several contributors to the illness. Psychological, biological and environmental factors may all contribute to its development. Whatever the specific causes, research has firmly established that major depression is a biological brain disorder.

Serotonin, norepinephrine and dopamine are three neurotransmitters (chemical messengers that transmit electrical signals between brain cells) thought to be involved with major depression. Several theories attempting to explain depression are based on an imbalance of these chemical messengers. It is thought that most antidepressant medications work by increasing the availability of neurotransmitters or by changing the sensitivity of the receptors for these chemicals.

Scientists have also found evidence of a genetic predisposition to major depression. There is an increased risk for developing depression when there is a family history of the illness. Not everyone with a genetic predisposition develops depression, but some people probably have a biological make-up that leaves them particularly vulnerable to developing depression. Life events, such as the death of a loved one, chronic stress, and alcohol and drug abuse, may trigger episodes of depression. Some illnesses such as heart disease and cancer and some medications may also trigger a depressive episode. Often, however, depressive episodes occur spontaneously and are not triggered by a life crisis or physical illness.

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The onset of the first episode of major depression may not be obvious if it is gradual or mild. The symptoms of major depression characteristically represent a significant change from how a person functioned before the illness. The symptoms of depression include:

• feelings of worthlessness, hopelessness, helplessness or guilt
• persistently sad or irritable mood
• pronounced changes in sleep habits and energy levels
• pessimistic feelings about the future
• trouble making decisions
• significant weight gain or loss
• difficulty thinking or concentrating
• low libido
• increased agitation
• lack of interest in or pleasure from activities typically enjoyed
• recurrent thoughts of death and/or suicide

When several of these symptoms occur at the same time, last longer than two weeks, and interfere with ordinary functioning, individuals should seek professional advice and treatment. If left untreated, major depression can lead to attempted suicide.

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Several types of treatment for major depression are available, and the type chosen depends on the individual and the severity of their illness. There are three basic types of treatment for depression in common use today: psychotherapy, medications and electroconvulsive therapy (ECT). They may be used singly or in combination. NeuroStar^® TMS Therapy is currently testing a fourth type.

Psychotherapy:  There are several types of psychotherapy that have been shown to be effective for depression including cognitive- behavioral therapy (CBT) and interpersonal therapy (IPT). Research has shown mild to moderate depression can often be treated successfully with either of these therapies used alone. Research on major depression suggests that this form of depression is more likely to respond to a combination of psychotherapy and medication.

• Cognitive-behavioral therapy (CBT) – helps to change the negative thinking and unsatisfying behavior associated with depression, while training people how to break the behavioral patterns that contribute to their illness.
  
  
• Interpersonal therapy (IPT) – focuses on improving troubled personal relationships and on adapting to new life situations that may have contributed to an individual’s depression.
  

Medication:  The first antidepressant medications were introduced in the 1950s. Research has shown that imbalances in neuro- transmitters like serotonin, dopamine and norepinephrine can be modulated with antidepressants. Five groups of antidepressant medications are most often prescribed for depression:

• Selective serotonin reuptake inhibitors (SSRIs) – useful as a first-line treatment, they act specifically on the neurotransmitter serotonin. In general, SSRIs cause fewer side effects than TCAs and MAOIs.
  
  
• Serotonin and norepinephrine reuptake inhibitors (SNRIs) – useful as first-line treatments in people taking an anti-depressant for the first time and for people who have not responded to other medications. In general, SNRIs cause fewer side effects than TCA and MAOIs.
  
  
• Dopamine reuptake blocker –  a newer antidepressant medication, it acts on the neurotransmitters dopamine and norepinephrine. In general, this class of medication causes fewer side effects than TCAs and MAOIs.
  
  
• Tricyclic antidepressants (TCAs) – still widely used for severe depression. TCAs elevate mood in depressed individuals, re-establish their normal sleep, appetite and energy level, but it often takes four to five weeks for an individual to respond.
  
  
• Monoamine oxidase inhibitors (MAOIs) – are often effective in individuals who do not respond to other medications or who have "atypical" depressions with marked anxiety, excessive sleeping, irritability, hypochondria or phobic characteristics.
  
  

Electroconvulsive therapy (ECT) - ECT is an effective treatment for severe depressive episodes. ECT employs the use of anesthesia and muscle relaxers during the procedure which involves the application of an electrical field to the head in order to produce a physical seizure. It can be done outpatient but is often done inpatient, depending on the patient’s particular situation.

For individuals where medication, psychotherapy, and a combination of the two prove to be ineffective, or work too slowly to relieve severe symptoms such as psychosis or thoughts of suicide, ECT is often used. ECT may also be indicated for those who are not able to take antidepressant medications and do not respond to psychotherapy.

Vagus Nerve Stimulation (VNS Therapy™) – is a non-drug treatment available specifically for treatment-resistant depression. The actual procedure takes about an hour and is usually performed under general anesthesia on an outpatient basis. Two small incisions are required: one on the upper chest area for the pulse generator and one on the left neck for the thin, flexible wires that connect the pulse generator to the vagus nerve.

Trancranial Magnetic Stimulation (TMS Therapy): TMS Therapy is an experimental procedure at this time. Scientists have been studying TMS Therapy in mood disorders since the mid 1990’s. Several hundred manuscripts have been published regarding its use in stimulating select regions of the brain. Neuronetics recently completed clinical trials that have evaluated the safety and efficacy of TMS Therapy as a treatment for major depression. Data from these trials have been provided to the US Food and Drug Administration (FDA) for use in determining if TMS Therapy should be made available for clinical use in the United States.

Note: Information on this site is for reference purposes only. It is not intended to be nor should it be taken as medical advice. Individuals who think they may suffer from major depression should see a medical professional regarding their symptoms.

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