Mental Disorders Common in America

Are mental illnesses becoming more prevalent, or is psychiatry overdiagnosing?

Medically Reviewed by Charlotte E. Grayson Mathis, MD
8 min read

In the span of a few months, Jacqueline Castine went from making $2,000 as a motivational speaker to getting fired from a minimum-wage post office job. She had successfully promoted a book on career enhancement, but then years later, was cleaning houses because she couldn't hold jobs elsewhere.

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The Michigan resident's highs and lows came to a head when, as a sales manager for a Detroit broadcasting outlet, she had a grand delusion that God was telling her to bankroll one of the station's charitable events.

The result: Castine ended up with a $43,000 credit card debt and thoughts of suicide.

"It was as if the bubble of unreality and distorted thinking had (burst)," says Castine, noting periods of despair coexisting with moments of great creativity. She sought psychiatric help and was diagnosed with bipolar disorder, also known as manic depression.

Mental Disorders Are Common

Castine's story may seem unique, but millions of Americans share her plight. According to the Depression and Bipolar Support Alliance, 3.7% of American adults have bipolar disorder, and 4 out of 5 of those who have it may not know it.

In the bigger picture of psychological illness, the statistics may be even more alarming. The National Institute of Mental Health (NIMH) reports that roughly 22% of U.S. adults -- about one in five -- suffer from a diagnosable mental disorder in a given year. According to the NIMH, about 1% of the population age 18 and older in any given year has bipolar disorder.

The numbers, however, may vary depending on the diagnostic criteria used by researchers, says William Narrow, MD, associate director of the division of research at the American Psychiatric Association (APA). He was part of the study that came up with the 22% figure cited by the NIMH.

That number, he says, may include people who may have a mild disorder -- those who may benefit from preventative treatment to keep symptoms from impairing their lives.

After reanalyzing the data, Narrow says the number of Americans with a mental disorder is closer to 15% in all ages. "I think it's more realistic in terms of who needs treatment acutely," he says.

Nonetheless, Narrow's study and several others indicate that psychological illnesses are common, and there is evidence that the problem may be growing.

Mental disorders account for a significant burden of disease in all societies. The World Health Organization (WHO) projects that mental disorders will increase from nearly 12% of the all diseases worldwide to almost 15% by the year 2020.

The statistics have experts emphasizing the need for more awareness and treatment, and skeptics blaming psychiatry for going overboard with overdiagnosing ordinary problems.

The debate unearths the contentious issue of where to draw the line between what is normal behavior and what is considered part of a mental illness.

A Different World

There is dispute over whether a greater number of people have psychological illnesses now compared with past generations, or whether there is just more awareness of the subject and more folks are diagnosed.

Some experts say depression and anxiety boost the number of people with mental disorders.

"Depression and anxiety are the common colds of the psychiatric field in that they come and go without getting treatment," says C. David Jenkins, PhD, adjunct professor of epidemiology and psychiatry for the University of North Carolina at Chapel Hill.

By analogy, he says the number of respiratory illness would rise if the number of people with the common cold were included.

In his study of air traffic controllers, Jenkins found many of them met the criteria for depression or anxiety for a month or two, and then they would "straighten up, and feel a lot better, until maybe six to eight months later when they would have another month that was a little low."

Yet these mood disorders -- depression and anxiety -- do not always "come and go" so easily. Without treatment, the disorders can prevent people from living productive lives, says Kathy HoganBruen, PhD, senior director of prevention for the National Mental Health Association.

HoganBruen says she is not sure why the mental disorder numbers are so high, but she's not surprised that they are. "In our society, there are lots of potential stressors," she says, pointing to the uncertain economy, terrorism , worries about parenting, and health care as part of the gamut of concerns.

Indeed, the stress-related version of mental illness is what's on the rise, says Ron Kessler, PhD, professor of health care policy at Harvard Medical School, distinguishing between conditions such as depression and anxiety (which are mostly caused by biological and environmental factors), and what he says are largely genetic conditions such as schizophrenia and bipolar disorder.

The global rates of schizophrenia and bipolar disorder have, for the most part, not changed, says Kessler, while depression and anxiety disorders are more common.

He says urbanization probably had a role in the rise of stress-related mental disorders. "People are moving to cities, moving far away from where their parents lived, and having jobs that their fathers didn't have before," says Kessler.

Urbanization, according to the WHO, is accompanied by increased homelessness, poverty, overcrowding, disruption of family structure, and loss of social support, all of which are risks for mental disorders.

With the uncertainty of the future and fewer family and community ties to help deal with problems, Kessler says more people become anxious, breeding secondary depression, and the two are associated with drinking and using drugs.

"That triumvirate of anxiety, depression, and substance abuse -- those are the ones that are changing," he says. "There's a lot of thinking that anxiety is right at the core of it. That's sort of the foundation."

Anxiety may also be heightened by other factors related to modern society, such as globalization and more advanced technology.

"Right now the whole world is at our fingertips, no further away than the television screen, and I believe we get churned up, and our view of everything going to the dogs is heightened by our easy access to all this information," says Jenkins.

At the same time, he says expectations now are higher than they were many years ago. People now expect to have jobs, enough money to go to a dinner and movie, and many kids expect to have a cell phone in high school and a car at graduation.

Shades of Gray

What type of behavior is considered normal and what classifies as a mental disorder? When is it appropriate to treat a problem with drugs? These questions often spark controversy in and out of the psychiatric field.

The 1999 U.S. Surgeon General's report on mental health defines mental disorders as "health conditions that are characterized by alterations in thinking, mood, or behavior (or some combination thereof) associated with distress and/or impaired functioning."

Critics, however, have questioned the extent to which psychiatry has labeled thinking, mood, and behavior. There are charges of overdiagnosing people and "medicalizing" troublesome characteristics, thoughts, and actions.

The criticism seems to intensify when kids are involved and when prescribing them drugs is at issue.

In 1996, the United Nations' International Narcotics Control Board raised concern about the increasing use of the stimulant Ritalin for the treatment of ADHD in children, particularly in the U.S. Authorities reporting to the board said the disorder may be diagnosed too often and the stimulant prescribed without considering other types of treatment.

Many mental health professionals have little doubt that there are people who are either misdiagnosed, overdiagnosed, or given drugs too easily.

Yet the much bigger problem, says HoganBruen, is that people who need help are not being assessed or treated for mental health disorders.

The exact point when normal problems become a disorder needing treatment is apparently tough to figure out, even with the APA's Diagnostic and Statistical Manual of Mental Disorders (DSM) -- the reference guide used by professionals to classify psychiatric symptoms.

"There is a continuum between normal behavior and abnormal behavior for a lot of different symptoms," says Narrow. Nonetheless, psychiatrists make diagnoses the best they can by considering how severe symptoms are and how much they impair daily life.

Sometimes medicine draws the illness line at the point where doctors know how to treat, suggests Kessler. "If it turned out that some pill was developed tomorrow ... and it would make (problems) go away ... we would declare it in an illness, and we would start treating it," he says.

While psychiatry continues to search for more effective treatments and a better understanding of mental disorders, there are some remedies - including drugs -- that are scientifically proven to work.

Kids with ADHD who receive treatment are less likely later in life to get divorced, be on welfare, get into trouble with the law, or be dead, says Kessler.

Mental illness is and always has been a burden on society, even though the problem was not discussed as openly in the past, says Narrow.

According to the WHO, estimates from the year 2000 have placed mental disorders as six of the top 20 leading causes of disabilities worldwide.

Among children, the APA reports that ADHD is the most commonly diagnosed mental health condition in the U.S. According to the Surgeon General's Report on Mental Health, ADHD afflicts between 3% and 5% of school-age children in any six month period.

As bleak as the reports may seem, HoganBruen says there is effective treatment and it's possible, with treatment, to lead productive lives.

A Brighter Outlook

Castine says she didn't think there was anything to live for when she lost all her money while suffering with bipolar disorder. But after taking medication and working with a therapist, she was able to find a job as a community education specialist, publicly speaking about her personal experiences with mental illness.

The 63-year-old now has plenty of savings in the bank and hopes to earn enough for retirement from the publication of her next book, due out this summer.

If you suspect that you or a loved one might have a mental disorder, experts suggest a visit to a primary care doctor or a mental health professional.