|Mental Illness Exacts Heavy Toll,
Beginning in Youth
Researchers supported by the National Institute of
Mental Health (NIMH) have found that half of all lifetime
cases of mental illness begin by age 14, and that despite
effective treatments, there are long delays — sometimes
decades — between first onset of symptoms and
when people seek and receive treatment. The study also
reveals that an untreated mental disorder can lead to
a more severe, more difficult to treat illness, and
to the development of co-occurring mental illnesses.
The landmark study is described in four papers that
document the prevalence and severity of specific mental
disorders. The papers provide significant new data on
the impairment — such as days lost from work — caused
by specific disorders, including mood, anxiety, and
substance abuse disorders. These measures will allow
researchers to determine the degree of disability and
the economic burden caused by mental illness, as well
as trends over time.
The papers are reported in the June 6 issue of the
Archives of General Psychiatry by Ronald Kessler, Ph.D.,
and colleagues. The study was a collaborative project
between Harvard University, the University of Michigan,
and the NIMH Intramural Research Program.
This study, called the National Comorbidity Survey
Replication (NCS-R), is a household survey of 9,282
English-speaking respondents, age 18 and older. It is
an expanded replication of the 1990 National Comorbidity
Survey, which was the first to estimate the prevalence
of mental disorders (using modern psychiatric standards)
in a nationally representative sample. The expansion
includes detailed measures that will significantly improve
estimates of the severity and persistence of mental
disorders, and the degree to which they impair individuals
and families, and burden employers and the U.S. economy.
“These studies confirm a growing understanding about
the nature of mental illness across the lifespan,” says
Thomas Insel, M.D., Director of the National Institute
of Mental Health. “There are many important messages
from this study, but perhaps none as important as the
recognition that mental disorders are the chronic disorders
of young people in the U.S.”
Prevalence and Age-of-Onset of Mental Disorders
Unlike most disabling physical diseases, mental illness
begins very early in life. Half of all lifetime cases
begin by age 14; three quarters have begun by age
24. Thus, mental disorders are really the chronic
diseases of the young. For example, anxiety disorders
often begin in late childhood, mood disorders in late
adolescence, and substance abuse in the early 20’s.
Unlike heart disease or most cancers, young people
with mental disorders suffer disability when they
are in the prime of life, when they would normally
be the most productive.
The risk of mental disorders is substantially lower
among people who have matured out of the high-risk age
range. Prevalence increases from the youngest group
(age 18-29) to the next-oldest age group (age 30-44)
and then declines, sometimes substantially, in the oldest
group (age 60 +). Females have higher rates of mood
and anxiety disorders. Males have higher rates of substance
use disorders and impulse disorders.
The survey found that in the U.S., mental disorders
are quite common; 26 percent of the general population
reported that they had symptoms sufficient for diagnosing
a mental disorder during the past 12 months. However,
many of these cases are mild or will resolve without
It is likely, however, that the prevalence rates in
this paper are underestimated, because the sample was
drawn from listings of households and did not include
homeless and institutionalized (nursing homes, group
homes) populations. In addition, the study did not assess
some rare and clinically complex psychiatric disorders,
such as schizophrenia and autism, because a household
survey is not the most efficient study design to identify
and evaluate those disorders.
Failure and Delay in Initial Treatment Contact
The study documents the long delays between the onset
of a mental disorder and the first treatment contact,
as well as the accumulated burden and hazards of untreated
These pervasive delays in getting treatment tend to
occur for nearly all mental disorders, though they vary
according to specific diagnostic categories. The median
delay across disorders is nearly a decade; the longest
delays are 20-23 years, for social phobia and separation
anxiety disorders. This is possibly due to the relatively
early age of onset and fears of therapy that involve
Shorter delays between onset of disorder and treatment
seeking — still a protracted 6-8 years — are
seen for mood disorders, and are likely attributable
to public awareness campaigns, the marketing of newer
therapies directly to consumers, and expanded insurance
While approximately 80 percent of all people in the
U.S. with a mental disorder eventually seek treatment,
there are public health implications from such long
delays in treatment. Untreated psychiatric disorders
can lead to more frequent and more severe episodes,
and are more likely to become resistant to treatment.
In addition, early-onset mental disorders that are left
untreated are associated with school failure, teenage
childbearing, unstable employment, early marriage, and
marital instability and violence.
“The pattern appears to be that the earlier in life
the disorder begins, the slower an individual is to
seek therapy, and the more persistent the illness,” said
Dr. Kessler, a professor of health care policy at Harvard
Medical School. “It’s unfortunate that those who most
need treatment are the least likely to get it.”
Treating cases early could prevent enormous disability,
before the illness becomes more severe, and before co-occurring
mental illnesses develop, which only become more difficult
to treat as they accumulate, according to the researchers.
Severity and Comorbidity of Mental Disorders
The second paper reports that even though mental disorders
are widespread throughout the population, the main
burden of illness is concentrated in those with a
severe disorder — about 6 percent. A “serious” disorder
involves a substantial limitation in daily activities
or work disability, or a suicide attempt with serious
lethal intent, or psychosis. The serious group reported
a mean of 88.3 days — nearly 3 months of the
year — when they were unable to carry out their
normal daily activities.
Unfortunately, say the researchers, individuals with
one mental disorder are at a high risk for also having
a second one (comorbidity). Nearly half (45 percent)
of those with one mental disorder met criteria for two
or more disorders, with severity strongly related to
comorbidity. This finding supports the suggestion by
a growing portion of researchers that the boundaries
between some diagnostic categories may be less discrete
than previously believed.
Use of Mental Health Services
The study indicates that the U.S. mental health care
system is not keeping up with the needs of consumers
and that improvements are needed to speed initiation
of treatment as well as enhance the quality and duration
of treatment. For instance, over a 12-month period,
60 percent of those with a mental disorder got no
treatment at all.
The good news is that the proportion of people who
reported 12-month mental health service use is higher
now — at 17 percent — than a decade ago in the baseline
NCS survey, at 13 percent. The expansion was mainly
in the general medical sector, with more primary care
physicians providing psychiatric services.
People with mental or substance abuse disorders were
more likely to get treatment from a primary care physician/nurse
or other general medical doctor (22.8 percent), or from
a non-psychiatrist mental health specialist (16 percent),
such as a psychologist, social worker, or counselor,
than from a psychiatrist (12 percent), though the survey
did show that the adequacy of treatment — measured
by number of visits — is best when provided by
mental health practitioners. About 9.7 percent sought
help from a counselor or spiritual advisor outside of
a mental health setting; and 6.9 percent used a complementary-alternative
source, such as a chiropractor or self-help group. This
held true even for those with severe mood disorders.
Traditionally underserved groups, such as the elderly,
racial/ethnic minorities and those with low income or
without insurance, had the greatest unmet need for treatment.
Future and Ongoing Efforts
The NIMH epidemiological research portfolio contains
several related projects that are focused on mental
disorders among adolescents and ethnic subgroups.
These include 1) an arm of the NCS-R that is studying
10,000 youths; 2) the National Study of African American
Life, with 6,000 participants; and 3) the National
Study of Latino and Asian Americans, with 5,000 participants.
Each of these, like the NCS-R, will provide information
on diagnosis, medications, disability/impairment,
and service use, drawing from nationally based samples.
An international perspective on these findings is also
becoming available, as the study is part of a global
initiative on the epidemiology of mental disorders in
28 countries, coordinated through the World Health Organization.
NIMH is part of the National Institutes of Health
(NIH), the Federal Government's primary agency for
biomedical and behavioral research. NIH is a component
of the U.S. Department of Health and Human Services.