After years of research, debate, and revision, the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders is hitting the shelves.
The release of the DSM-5 marks the first time the influential diagnostic manual has been updated in nearly 20 years. The goal in putting together the fifth edition was not to do anything radical, said Dr. Dilip V. Jeste, president of the American Psychiatric Association, but to bring the science up to date and to make it more user friendly for clinicians.
Courtesy APA/David Hathcox
Dr. Dilip Jeste
"The goal is to make sure that we have more accurate diagnoses so we can get better mental health services and improve patient outcomes," Dr. Jeste said.
The DSM-5 moves from a multiaxial system to a single axis format. It didn’t make sense to separate the disorders in that way, Dr. Jeste said, and the change makes it simpler for psychiatrists to use. The DSM-5 also puts a greater focus on the roles of age, gender, and culture. Every chapter will include a section on how to apply these factors when making a diagnosis.
Overall, the DSM-5 is not significantly different from the DSM-IV, said Dr. Joel Paris, a professor of psychiatry at McGill University, Montreal, and author of the "The Intelligent Clinician’s Guide to the DSM-5" (New York: Oxford University Press, 2013). Psychiatrists do not need to worry that they will be dealing with a completely new manual, he said, because most of the controversial changes were not accepted in the final version of the manual.
Dr. Paris, who was not involved in the DSM revision, said some those big changes were rejected by the DSM-5’s Scientific Review Committee because they did not have enough scientific data to back them up. "We’re just starting the science of psychiatry," he said. "It’s early days."
But there are some notable changes in the new manual. Experts who worked on the DSM-5 highlighted some of the revisions most likely to affect the way in which how psychiatrists practice.
Mild neurocognitive disorder
In the DSM-5, neurocognitive disorders are divided into two subtypes: mild and major. Major neurocognitive disorder lines up with the DSM-IV definition of dementia. But the DSM-5 Neurocognitive Disorders Work Group created a new subtype to describe mild neurocognitive decline that is more severe than the normal forgetfulness of aging but doesn’t rise to the level of dementia.
The DSM-5 includes specific criteria to help make the diagnosis of mild neurocognitive disorder, said Dr. Dan G. Blazer, cochair of the Neurocognitive Disorders Work Group and a professor of psychiatry and behavioral sciences at Duke University in Durham, N.C.
A patient with mild neurocognitive disorder is likely to complain of memory problems but will not have significant cognitive problems and would not meet the criteria for major neurocognitive disorder. Such patients often are able to complete their daily tasks, but it takes significantly more time and effort. For instance, a patient with mild neurocognitive disorder might take 2 hours to balance a checkbook, when it took just 10 minutes in the past.
Patients with mild neurocognitive disorder should fall somewhere between 1-2 standard deviations below normal on neuropsychological tests, Dr. Blazer said. While the DSM-5 does not recommend a specific test, Dr. Blazer said using some type of standardized test is important. "As we move along in this field, it’s going to be very important to objectively document the level of cognitive impairment that individuals have," Dr. Blazer said.
One of the challenges with this diagnosis is the question of whether these patients will progress and develop dementia. The answer is not necessarily, Dr. Blazer said. While this group has a higher likelihood of progressing to more severe problems, it is not a diagnosis of "pre-dementia," he said.
For many psychiatrists, the biggest change will be to begin asking patients about their level of functioning when they come in with memory complaints. That’s something that can be easily overlooked in a busy practice, Dr. Blazer said.
Major neurocognitive disorder
Previously memory impairment was essential to making a diagnosis of dementia, now called major neurocognitive disorder. But the DSM-5 no longer requires memory impairment to be present, said Dr. Jeste, who served on the Neurocognitive Disorders Work Group and is a professor of psychiatry and neurosciences at the University of California, San Diego.
The change was made to acknowledge that there are major neurocognitive disorders in which memory impairment is not present until late in the course of the illness. For instance, with frontotemporal dementia, which can occur when the patient is aged 50 years, memory impairment does not become apparent until much later in life. Instead, the main symptom is a change in personality. The change will likely reduce the number of patients who receive a "not otherwise specified" (NOS) diagnosis, Dr. Jeste said.