- Mental disorders are the No. 1 cause of disability for people ages 15-45 in the developed world.
- There are 33,000 suicides every year in the US—twice as many suicides as homicides.
life expectancy of people with serious mental illnesses like
schizophrenia, 56, is 25 years earlier than the population at large.
- There are three times as many people with serious mental illness in jails and prisons than in hospitals.
These statistics define where we are in the field, said Thomas Insel,
director of the National Institute of Mental Health and a member of the
Dana Alliance for Brain Initiatives. But the field will be transformed
in coming decades, he argues, as what we learn from genetics, brain
science, and behavior come together to change how we diagnose, treat,
and think about mental illness.
Insel wrote a commentary on the topic in this week’s issue of JAMA; yesterday he elaborated on his ideas during a media briefing discussing the special issue, which focuses on mental illness.
For example, advances in genetics have led to the discovery of structural variations in the genome.
In mental illnesses like schizophrenia, autism, bipolar disorder, OCD,
and ADHD, researchers have found hundreds of common
variations—deletions or duplications in the genetic code—that have
“completely changed the way we think about genetics in psychiatric
disease,” he said.
These variations—all associated with
neurodevelopmental genes—“could not be associated with a single illness
even in the same family,” said Insel; the same variation could indicate
schizophrenia for one person, and autism for another. But they could
point to a more general risk for mental illness.
about brain circuitry also may change how we may view disorders. Much
mental illness is associated with the developing brain—the age of onset
peaks in the teen years, when the brain’s grey matter is undergoing a
“pruning effect” and becoming more efficient. Some disorders might be
described as “poor pruning.”
For example, it may be that
people likely to develop schizophrenia lose too many synapses during
this period, Insel suggested. He hopes that by 2020, we can detect
schizophrenia before psychosis begins. “We are going to shift the curve
and get earlier in diagnosis and treatment,” intervening when people
have risk factors but before they have symptoms.
This may lead
to a change in the way diseases are defined. “We have been locked into
presentation,” said Insel, citing the way the DSM
characterizes diseases by symptoms, not underlying causes. “Most of
medicine has moved beyond that. We want to add all the things we can’t
see,” like genetics and imaging.
In a decade, predicts Insel, “We will have entirely different names and ways of thinking about disorders.”