Serious Mental Illnesses

Four major mental illnesses tend to be the most serious:

  • Major depression
  • Schizophrenia
  • Schizoaffective disorder
  • Bipolar disorder

Major Depression (source: National Alliance on Mental Illness [NAMI])

Major depression is a serious medical illness affecting 6.7 percent of American adults or 14.8 million people. In any given year, major depression affects 5–8 percent of the adult population. Unlike normal emotional experiences of sadness, loss or passing mood states, major depression is persistent and can interfere significantly with an individual's thoughts, behavior, mood, activity and physical health. Among all medical illnesses, major depression is the leading cause of disability in the United States and many other developed countries.

Schizophrenia (source: NAMI)

Schizophrenia is a serious mental illness that affects 1.1 percent of American adults or about 2.6 million people. Although it affects men and women with equal frequency, schizophrenia most often appears in men in their late teens or early 20s, and in women in their late 20s or early 30s. Finding the causes for schizophrenia is difficult since the cause and course of the illness is unique for each person.

Schizophrenia interferes with a person's ability to:

  • Think clearly
  • Manage emotions
  • Make decisions
  • Relate to others

If untreated, schizophrenia impairs a person’s ability to function to his or her potential. Unfortunately, no single, simple course of treatment exists. Research has linked schizophrenia to a multitude of possible causes including aspects of brain chemistry and structure as well as environmental causes.

Schizoaffective Disorder (source: NAMI)

Schizoaffective disorder is one of the more common, chronic and serious mental illnesses. As the name implies, it is characterized by symptoms of schizophrenia and an affective, or mood, disorder. There has been controversy about whether schizoaffective disorder is a type of schizophrenia or a type of mood disorder. Today, most clinicians and researchers agree that it is primarily a form of schizophrenia.

Although the exact prevalence of schizoaffective disorder is unclear, it may range from two to five in 1,000 people. Schizoaffective disorder may account for one-fourth or even one-third of all persons with schizophrenia.

Bipolar Disorder (source: NAMI)

Bipolar disorder, or manic depression, is a medical illness that causes extreme shifts in mood, energy and functioning. These changes may be subtle or dramatic and typically vary greatly over the course of a person's life as well as among individuals.

About 2.6 percent of American adults – 6.1 million people – have bipolar disorder, and the illness affects men and women equally. Bipolar disorder is a chronic and generally lifelong condition with recurring episodes of mania and depression that can last from days to months. These episodes often begin in adolescence or early adulthood and occasionally even in children.

Generally most people require some sort of lifelong treatment. While medication is one key component for successfully treating bipolar disorder, other essential components include:

  • Psychotherapy
  • Support
  • Education about the illness