According to the National Alliance of the Mentally Ill, severe mental illnesses are more common than cancer, diabetes or heart disease.
About one in five adults suffer from a diagnosable mental disorder in their lifetime. Estimates from the U.S. surgeon general show that about 23 percent of the country's population, roughly 44 million people, have diagnosable mental disorders. Up to 30 percent of the population have either a mental or addictive disorder.
Statistics for Nevada vary, but estimates from the Center for Mental Health Services indicate that about 236,000 people of all ages in Nevada suffer from some form of a mental illness.
"Who are those people? Well, they're everybody," said David Schroeder, a clinical psychologist and coordinator of clinical services at Carson-Tahoe Hospital's Behavioral Health Services. "People with mental illness generally fit into two categories. There are the mentally ill that because of their illness are chronically debilitated.
"Those are the people with schizophrenia, severe, severe depression, bipolar disorder. They can't work. Their medications are barely able to hold them together. They're probably poor because they can't work. The have poor problem-solving skills, poor coping skills. They can't cope in the world very well. That's a pretty small number, maybe five to 15 percent of the mentally ill population.
"The other people are those who in suffering the slings and arrows of life fall off their pony. Medications and or therapy over time help them maintain a certain level of function. They're every person - the accountant, the teacher, they practice law. They are able to maintain normal lives like the rest of us."
Schroeder said mental illness was long considered to be a condition, not a disease.
"Traditionally, something was wrong with you. You pissed off God and now you're crazy," he said. "That was the superstition of the disease for a long time.
"There is a physical cause for the problem. Mental illness was the last disease concept to be accepted as a disease, something having a cause rather than being a state of existence. Only in the last two generations have we had this idea we can treat people with drugs and therapy to help peoples' mental illness."
The Surgeon General's report on mental illness also noted that costs associated with mental illness "are exceedingly high." About 7 percent of total heath spending is on mental health services, it notes.
About 10 percent of the population at any time struggles with mental illness, and Carson's numbers more than likely match that number, Schroeder said.
About mental illness
-- Severe mental illnesses are biologically-based brain diseases that profoundly disrupt a person's ability think, feel and relate to others or to their environment.
-- 5.4 million adults in the United States have a severe and persistent mental illness.
-- 11.4 million adults in the U.S. have a serious mental illness.
-- Rough estimates show that about 7.5 million youth have mental, behavioral or developmental disorders, yet only one-fifth of them receive treatment.
-- The leading reason for hospital admissions nationwide is psychiatric disorders.
-- Four of the 10 leading causes of disability in the U.S. and other developed countries are mental disorders: major depression, bipolar disorder, schizophrenia and obsessive-compulsive disorder.