Major depression, also called unipolar depression, which is the most common type of depression. It tends to be episodic, but can persistently recur. Symptoms must persist for at least two weeks.
Dysthymia, which is a chronic, unremitting depression. A dysthymia diagnosis requires fewer symptoms than major depression, but must be present for at least two years.
Bipolar disorder, also called manic depression, which is depression alternating with elated or irritable moods and increased energy.
Major depression and dysthymia is twice as prevalent among women than men: 1 in 4 women and 1 in 8 men will experience these types of depression at some point in their lives.
Many factors can cause depression, including biochemistry (a chemical imbalance of mood regulation in the brain), genetics, family history, substance abuse, and an illness or other difficult life events. Some people have mild depression, while in others depression is more severe.
Regardless of the cause, a person should be treated for depression. One-half of people with depression do not seek treatment because they don't understand their symptoms or have fear of the stigma of mental illness. Yet of those who do, 80% are treated effectively with medication, psychotherapy, or both.
Untreated depression is long lasting. A depressive episode, left untreated, can last six months, or chronically for years.
Depression is likely to recur. If a person experiences a single episode of depression, there is a 50% chance of having another. The chance of recurrence is 70% after two episodes and 90% after three episodes.
Depression can lead to suicide. Depression is the leading cause of suicide, and a suicide occurs every 17 minutes in the United States.
Bipolar Disorder (Manic Depression)
Bipolar disorder (manic depression) is a treatable biological medical condition that affects people of all genders, races, ages, and income levels. Roughly 5.7 million Americans (or 2.6% of the population) live with the condition. Bipolar disorder runs in families: more than two-thirds of people with bipolar disorder have at least one close relative with the condition or with major depression. Bipolar disorder can be mild to severe.
In addition to having periods of depression, people with bipolar disorder have periods of high energy where they can be happy or irritable. These mood swings can cycle in minutes or days or months.
Manic (high energy) symptoms include
Increased energy and decreased need for sleep
Excessive irritability, or euphoria, or aggressive behavior
Increased talkativeness or rapid speech
Disconnected and racing thoughts
Impulsive behavior and poor judgment such as spending sprees, erratic driving, or sexual indiscretions
Increased goal-directed activities
There are many successful, smart, and creative people with bipolar disorder - such as business leaders, actors, artists, and politicians - who, with treatment, lead healthy lives. Unfortunately, bipolar disorder is vastly under-diagnosed and under-treated. On average, a person spends 8 years seeking treatment before bipolar disorder is diagnosed. During that time a person suffers needlessly and is at risk for suicide.
Fifty percent of people with bipolar disorder lack insight or do not realize they are ill. For example, they may believe they are a "high energy person." Often they only go to a doctor complaining of their depression, so the doctor does not realize they also have periods of mania. Therefore, it is essential that family members and friends report manic symptoms to the doctor, so that they can make an accurate diagnosis.
People with bipolar disorder can be effectively treated with medication (e.g., mood stabilizer), a different class of medication than antidepressants. Antidepressants alone can sometimes make their condition worse (International Society for Bipolar Disorders, task force on antidepressant use in bipolar disorders, American Journal of Psychiatry, November 2013). Along with medication, therapy (family-focused therapy, cognitive behavioral therapy, and/or individual therapy) is proven to be effective.