The new Diagnostic and Statistical Manual of Mental Disorders, 5th Edition (DSM-5) has a number of changes to neurocognitive disorders, including Alzheimer’s dementia and delirium. This article outlines some of the major changes to these conditions.
According to the American Psychiatric Association (APA), the publisher of the DSM-5, the major change in this category of disorders is the addition of “mild neurocognitive disorder.” The APA believes provides an opportunity for early detection and treatment of cognitive decline before patients’ deficits become more pronounced and progress to major neurocognitive disorder (dementia) or other debilitating conditions. Its inclusion in the manual will help clinicians develop effective treatment plans as well as encourage researchers to evaluate diagnostic criteria and potential therapies.
The criteria for delirium have been updated and clarified on the basis of currently available research, according to the APA.
Major and Mild Neurocognitive Disorder (NCD)
This is a new diagnostic category in the DSM-5, but subsumes some existing DSM-IV disorders. The APA acknowledges that although the threshold between mild NCD and major NCD is inherently arbitrary, there are important reasons to consider these two levels of impairment separately:
The major NCD syndrome provides consistency with the rest of medicine and with prior DSM editions and necessarily remains distinct to capture the care needs for this group. Although the mild NCD syndrome is new to DSM-5, its presence is consistent with its use in other fields of medicine, where it is a significant focus of care and research, notably in individuals with Alzheimer’s disease, cerebrovascular disorders, HIV, and traumatic brain injury.
Major Neurocognitive Disorder
This new category pulls together a set of existing mental disorder diagnoses from the DSM-IV, including dementia and amnestic disorder. (According to the APA, you can still use the term dementia to refer to that condition if you’d like.)
Mild Neurocognitive Disorder
Mild neurocognitive disorder goes beyond normal issues of aging, but doesn’t yet rise to the level of a major neurocognitive disorder. Mild NCD describes a level of cognitive decline that requires the person be engaging in compensatory strategies and accommodations to help maintain independence and perform activities of daily living.
To be diagnosed with mild NCD, there must be changes that impact cognitive functioning. These symptoms are usually observed by the individual, a close relative, or other knowledgeable informant, such as a friend, colleague, or clinician, or they are detected through objective testing.
The APA suggests there has been a strong need for the new category of mild neurocognitive disorder:
There is substantial clinical need to recognize individuals who need care for cognitive issues that go beyond normal aging. The impact of these problems is noticeable, but clinicians have lacked a reliable diagnosis by which to assess symptoms or understand the most appropriate treatment or services.
Recent studies suggest that identifying mild neurocognitive disorder as early as possible may allow interventions to be more effective. Early intervention efforts may enable the use of treatments that are not effective at more severe levels of impairment and may prevent or slow progression. Researchers will evaluate how well the new diagnostic criteria address the symptoms, as well as potential therapies like educational or brain stimulation.
When previously diagnosing dementia, clinicians could use a number of different criteria sets, to designate whether the dementia was of the Alzheimer’s type, vascular dementia, or substance-induced dementia. Other similar disorders in the DSM-IV were classified as dementia due to another medical condition: with HIV, head trauma, Parkinson’s disease, Huntington’s disease, Pick’s disease, Creutzfeldt-Jakob disease, and so on.
This has changed somewhat in the DSM-5, according to the APA:
[M]ajor or mild vascular NCD and major or mild NCD due to Alzheimer’s disease have been retained, whereas new separate criteria are now presented for major or mild NCD due to frontotemporal NCD, Lewy bodies, traumatic brain injury, Parkinson’s disease, HIV infection, Huntington’s disease, prion disease, another medical condition, and multiple etiologies. Substance/medication-induced NCD and unspecified NCD are also included as diagnoses.