Neurocognitive Disorders

Question 1

Why is the study of cognitive disorders important in neurocognitive research?

Answer 1

These disorders are common in adulthood, especially in later life, contrasting with early developmental disorders.

They encompass a variety of disorders classified within the DSM, making them a rich area for exploration.

They highlight ethical issues, such as the challenges of conducting research and providing interventions for individuals with impaired cognition and the complexities of obtaining informed consent.

Boundary issues are prevalent, as cognitive features often overlap with non-cognitive
psychopathology, such as personality or mood changes, which complicate diagnosis.

Question 2

Are neurocognitive disorders (NCDs) common, and which specific types are often studied?

Answer 2

Yes, neurocognitive disorders are common.

However, using the umbrella term “NCD” can be less useful in clinical discussions. A more focused approach is to study specific exemplars, such as neurocognitive disorders due to Alzheimer’s disease and delirium, which provide more insight into the different presentations and challenges within this category.

Question 3

At what age do cognitive disorders typically appear, and how does their prevalence change with age?

Answer 3

Cognitive disorders tend to first appear around the ages of 50-60. However, their prevalence increases rapidly after the age of 70. For example, the prevalence of Alzheimer’s disease among individuals aged 75-84 was 2.4% in 2010 and is projected to increase significantly, reaching 5.0% by 2040 for the same age group. The prevalence among those aged 85 and above is projected to rise from 2.4% in 2010 to 8.0% by 2050.

Question 4

How common is delirium, and what are its associated risk factors?

Answer 4

Delirium is present in approximately 10-15% of individuals admitted to acute care facilities, such as emergency rooms (ERs). It is more common with increasing age and is often associated with substance use or other medical conditions. These can include general medical conditions or cases of substance-induced delirium.

Question 5

What distinguishes neurocognitive disorders (NCDs) from other disorders in the DSM-5 regarding diagnosis?

Answer 5

Neurocognitive disorders (NCDs) are distinguished by a stronger neuropathological or biological component than other disorders. Although there is a desire to rely entirely on biomarkers for diagnosis, in practice, clinical diagnosis still plays a significant role. In NCDs, diagnostic criteria are met by combining signs, symptoms, and patient history, but there is greater emphasis on biomarker tests compared to other disorders.

Question 6

What role do cognitive features and neurodegeneration play in defining neurocognitive disorders (NCDs)?

Answer 6

In NCDs, cognitive changes are the primary feature, unlike in other disorders where mood or emotional symptoms might dominate. Additionally, many NCDs are neurodegenerative, meaning their cause is often unknown, they progressively worsen over time, and they generally lack effective cures. This makes them harder to treat with psychotherapies compared to non-neurodegenerative disorders.

Question 6

What are some ethical dilemmas associated with diagnosing Alzheimer’s disease (AD) and other neurocognitive disorders?

Answer 6

Purpose of diagnosis without treatment: If no effective treatment is available, the value of an early diagnosis becomes questionable.

Early diagnosis vs. confirmed diagnosis: There is pressure to diagnose early, but it risks sacrificing accuracy and sensitivity in clinical assessments.

Consent for treatment and research: As cognitive abilities decline, it becomes challenging to determine a person’s capacity to give informed consent for interventions and participation in research.

Question 7

How has the conceptualization of mental disorders evolved from earlier thinking to the current model in the DSM?

Answer 7

Earlier thinking divided mental disorders into two categories:

Organic disorders: Physical illness-based, with a physical or cognitive processing cause.
Functional disorders: Also known as “brain syndromes,” focusing on abnormal brain function without a clear physical cause.

The current conceptualization recognizes that all mental illnesses may have some degree of organicity. This shift aligns with the biopsychosocial model, which integrates biological, psychological, and social factors in understanding psychopathology.

Question 8

What changes were introduced in the DSM-5 for the classification of neurocognitive disorders (NCDs)?

Answer 8

The DSM-5 added stimulant-induced mild NCD to the list of substance-induced NCDs (e.g., from alcohol, inhalants, or anxiolytic substances). It classifies NCDs into:

Delirium
Mild NCD: Requires disorder-specific criteria, such as for Alzheimer’s, Parkinson’s, or traumatic brain injury (TBI), and may involve behavioral disturbances.

Major NCD: Includes all features of mild NCDs but with increased severity, requiring the specification of severity and probability.

Question 9

What are the severity levels for major neurocognitive disorders (NCDs) in the DSM-5, and how are they determined?

Answer 9

Severe: Full dependence on all activities of daily living (ADLs).

Moderate: Requires help with basic ADLs, such as dressing.

Mild: Partial dependence, usually with more complex ADLs, such as managing finances.

Diagnosis involves integrating all specifiers (e.g., probable Alzheimer’s disease with behavioral disturbance) to provide a comprehensive assessment.

Question 10

What is the Behavioral Specifier in neurocognitive disorders (NCDs), and when is it used?

Answer 10

The Behavioral Specifier is used when neuropsychiatric features are present. In Alzheimer’s disease (AD), these features are referred to as Behavioral and Psychological Symptoms of Dementia (BPSDs), which include non-cognitive symptoms and behaviors. BPSDs are common in individuals with dementia, whether they are living at home or in inpatient and residential care settings.

Question 11

What challenges do Behavioral and Psychological Symptoms of Dementia (BPSDs) present for caregivers?

Answer 11

BPSDs contribute to caregiver burden due to:

Individuals being uncooperative.
Behaviors that disturb those around them.
Noticeable personality changes. These challenges can make caregiving highly demanding and are often a reason why families seek residential care placement for individuals with dementia.

Question 12

What are the key diagnostic criteria for delirium according to the DSM-5?

Answer 12

The DSM-5 defines delirium based on the following criteria:

Disturbance in attention and awareness (Criterion A).

Rapid onset and fluctuating presentation over a 24-hour period (Criterion B).

Additional cognitive
disturbances (Criterion C).

The symptoms are not explained by a pre-existing or emerging NCD (Criterion D).

There is evidence that the disturbance is caused by a physiological condition (Criterion E).

Question 13

How is delirium managed, and why is it considered a potentially reversible condition?

Answer 13

Delirium can be managed effectively if the underlying cause is identified and treated. For example, in older adults, an undiagnosed urinary tract infection (UTI) can impair attention and awareness, leading to delirium. Once the infection is treated, cognition can return to baseline, highlighting the reversibility of delirium. Additionally, delirium can manifest as hyperactive, hypoactive, or mixed activity, and treatment can be tailored to the specific subtype exhibited by the patient.

Question 14

What are the key diagnostic criteria for mild neurocognitive disorder (NCD) in the DSM-5?

Answer 14

Mild NCD is diagnosed based on:

Modest decline in one or more cognitive domains.

Concerns about the decline from the individual, an informant, or a clinician.

Objective assessment of cognitive performance, preferably through neuropsychological testing or other quantified clinical assessments when testing is not available.

A key difference from other disorders is that quantifiable testing is necessary for diagnosis, making it more structured.

Question 15

How does mild neurocognitive disorder (NCD) affect daily functioning, and what are the related ethical concerns?

Answer 15

Cognitive deficits in mild NCD do not interfere significantly with everyday functioning, though individuals may need reminders or greater effort to manage tasks.

Unlike other disorders, mild NCD focuses on cognitive decline without a direct impact on daily living, raising ethical concerns about the diagnosis. This is especially relevant when individuals cannot advocate for themselves, highlighting the need for careful assessment and consideration.

Deficits must not be due to delirium or other mental disorders, ensuring an accurate diagnosis within the appropriate context.

Question 16

What are the DSM-5 diagnostic criteria for major neurocognitive disorder (NCD)?

Answer 16

Significant decline in one or more cognitive domains based on concerns from the individual, informant, or clinician.

Substantial impairment in cognitive performance, preferably documented through neuropsychological testing or another quantified assessment.

The cognitive deficits interfere with everyday living, particularly with complex tasks.

Deficits must not be explained by delirium or another medical disorder.

Question 17

What is the diagnostic approach for identifying mild or major NCD, and how is the condition classified?

Answer 17

Determining whether the criteria for mild or major NCD are met.

Considering the neuropathology—whether an illness or tragic event has contributed to cognitive decline.

Adjusting the diagnosis by specifying the cause (e.g., “due to” Alzheimer’s disease or traumatic brain injury).

The diagnosis also includes specifiers for etiology, behavior, and severity, with some conditions requiring the assignment of probabilities.

Question 18

How is the onset and progression of MNCD due to Alzheimer’s disease different from other disorders like delirium?

Answer 18

The onset of MNCD due to Alzheimer’s disease is insidious and gradual, contrasting with the rapid onset of delirium. It takes years for cognitive impairment to evolve fully, with a slow transition from forgetfulness to needing reminders, and later to difficulties in recognizing family members, communicating, or performing basic activities like eating. If the condition is classified as major, at least two cognitive domains must be impaired.

Question 19

What steps are involved in diagnosing MNCD due to Alzheimer’s disease, according to the DSM-5?

Answer 19

Ensuring that criteria for mild or major NCD are met.

Ruling out other disorders that could explain the symptoms.

Identifying the presentation as possible or probable Alzheimer’s disease.

Excluding reversible causes of cognitive decline, such as treatable medical conditions. If no reversible causes are found, the diagnosis of Alzheimer’s disease is made.

Question 20

What determines whether Alzheimer’s disease is diagnosed as “possible” or “probable” according to DSM-5 criteria?

Answer 20

The DSM-5 defines probable Alzheimer’s disease if there is evidence of a causative genetic mutation. If no genetic evidence is present, the diagnosis depends on the severity (mild or major) and the extent of cognitive decline. In the absence of genetic confirmation, the diagnosis is “probable” if:

There is decline in memory and learning.

A detailed history or serial neuropsychological testing supports the diagnosis.

Question 21

How is Alzheimer’s disease distinguished from vascular dementia in terms of cognitive decline patterns?

Answer 21

Alzheimer’s disease shows a steady, progressive decline in cognitive abilities over time, without sudden drops or plateaus. This pattern contrasts with vascular dementia, where individuals experience step-wise deterioration—functioning at a certain level before a sudden decline, which can repeat. The progressive nature of Alzheimer’s is a key feature in distinguishing it from other types of dementia.

Question 22

What are common memory-related cognitive changes seen in individuals with Alzheimer’s disease?

Answer 22

Recent memory loss and short-term memory impairments, such as forgetting to turn off the stove or lock the door, posing safety risks.

Anterograde amnesia, where newly learned information is difficult to retain, though long-term memory often remains intact.

Physically, individuals may appear indistinguishable from others without the illness. They may engage well in conversations about past events, but struggle with recalling recent information, which is where the memory decline becomes apparent.

Question 23

What are the cognitive effects on movement, perception, and language in Alzheimer’s disease?

Answer 23

Movement – Apraxia:
Individuals struggle to execute commands, such as picking up a cup. Though they have the physical ability (e.g., strength and coordination), the cognitive process of hearing, processing, and executing the action is impaired.

Perception – Agnosia:
Patients cannot recognize familiar objects, such as distinguishing a fork from other utensils. This is a cognitive problem rather than a visual one, where the brain fails to process the recognition of the object.

Language – Aphasia:
Individuals experience word-finding difficulties, even though their fluency and motor skills for speech remain intact. This difficulty occurs due to cognitive impairment in retrieving and producing the correct word.

These cognitive impairments often co-occur with memory and learning difficulties, following a slow, progressive decline typical of Alzheimer’s disease.

Question 24

What is Allen Frances' main criticism of the DSM-5’s classification of mild neurocognitive disorder (NCD)?

Answer 24

Allen Frances criticizes the DSM-5 for mislabeling everyday forgetfulness associated with normal aging as Mild NCD, which he argues creates a false positive population of people not at actual risk for dementia. His concern is that, since there is no effective treatment for Mild NCD or dementia, this diagnosis provides no real benefit and instead causes unnecessary anxiety, even for individuals who might later develop dementia.

Question 25

What are some key diagnostic challenges in identifying neurocognitive disorders (NCDs)?

Answer 25

Acquired nature: NCDs must be distinguished from developmental cognitive issues. Interplay of factors: Cognitive problems may result from non-biological factors, such as depression, or an interaction between biological and psychological factors. Reversibility: Some conditions, like depression, can cause cognitive decline. If the primary cause is depression and it is treated, cognitive function may improve. This step is crucial before diagnosing NCDs like Alzheimer's disease. Differential diagnosis difficulties: It can be challenging to distinguish between dementia, delirium, and depression. Additionally, differentiating between NCDs due to Alzheimer's disease versus Lewy body dementia is particularly complex, making these distinctions notoriously difficult.

Question 25

What are the key differences between delirium and dementia based on symptom presentation?

Answer 25

Delirium Disturbed level of consciousness: Yes Onset: Rapid Daily symptom fluctuation: Yes Multiple etiologies: Yes Estimated incidence in the population aged 65+: 10% Dementia Disturbed level of consciousness: No Onset: Progressive Daily symptom fluctuation: No Multiple etiologies: Yes Estimated incidence in the population aged 65+: 2-4%

Question 26

What are the key differences between depression and dementia in terms of symptom progression and behavior?

Answer 26

Depression Progression: Uneven, over weeks Memory: Complains of memory loss Symptoms: Worse in the morning Awareness: Aware of and may exaggerate disability Substance Use: May abuse alcohol or other drugs (AOD) Dementia Progression: Even, over months or years Memory: Attempts to hide memory loss Symptoms: Worse in the evening or when fatigued Awareness: Unaware of or minimizes disability Substance Use: Rarely abuses alcohol or other drugs

Question 26

Why is the differential diagnosis between dementia, depression, and delirium challenging?

Answer 26

Symptom overlap, especially as depression in the elderly can resemble cognitive decline. Comorbidity: Around 25% of people with dementia also show symptoms of major depressive disorder. The DSM-5 suggests discrete subtypes of dementia, but neuropathology and clinical presentations may be mixed or poorly correlated.

Question 27

What role do biomarkers play in diagnosing mild cognitive impairment (MCI) and dementia?

Answer 27

Biomarkers, such as amyloid-β accumulation detected through CSF or PET scans, can indicate brain changes before clinical symptoms appear. Biomarkers are critical in the diagnostic process since: Cognitive decline becomes evident later on (e.g., line 5 on the graph, just before an MCI diagnosis). If early biomarker detection is used, it could potentially prevent dementia development by intervening before symptoms arise.

Question 28

What are the limitations and challenges of diagnosing MCI as a prodromal stage of dementia?

Answer 28

Conversion rates from MCI to dementia can be as low as 10% within a year. Some individuals diagnosed with MCI may return to normal functioning after serial testing. This variability questions the reliability of MCI as a predictor for dementia, and having the diagnosis doesn't ensure future cognitive decline. This raises the critical question of when DSM-5 should flag MCI for early intervention, given the uncertainty.

Question 29

Why is differential diagnosis between dementia, depression, and delirium important, and what challenges does it present?

Answer 29

Differential diagnosis is critical because different conditions require distinct treatments and have varying prognoses. However, the distinctions between these conditions are often more complex than they appear in tabulated forms. While the tables offer useful heuristics, they must be applied critically in practice, as the boundaries between dementia, depression, and delirium are not always clear-cut.

Question 30

What are the key factors affecting the etiology of neurocognitive disorders (NCDs)?

Answer 30

The etiology of NCDs depends on the specifier used and can involve localized or diffuse pathologies that affect either specific regions or the entire brain. Some NCDs, like Huntington’s disease, have a known genetic cause, while others, such as Alzheimer's disease, are often idiopathic—occurring without a family history, with genetic mutations only increasing risk. Physical, biological, and structural factors are more influential in the etiology of NCDs, with psychological or social factors playing a smaller role.

Question 31

Why are many neurocognitive disorders (NCDs) considered degenerative, and how does their onset differ?

Answer 31

Many NCDs are degenerative, meaning they have no known cure and progressively worsen over time. In conditions like Alzheimer's disease, the onset is gradual and diffuse, as shown through neuroimaging. Other conditions, such as those caused by traumatic brain injury (TBI) or stroke, may have a sudden onset due to localized damage in the brain. These differences highlight the diverse presentations and progression paths across various NCDs.

Question 32

How is the treatment of neurocognitive disorders (NCDs) determined, and what are the challenges in treating them?

Answer 32

Treatment depends on the presumptive neuropathology: If treatable, efforts focus on reversing the cause (e.g., addressing reversible conditions). If irreversible, treatment typically involves managing secondary symptoms using medication (e.g., sleeping aids for sleep issues). The focus shifts from “treatment” to management for incurable NCDs, emphasizing quality of life rather than cure.

Question 33

What future biological treatments and diagnostic methods are being explored for Alzheimer's disease?

Answer 33

There is significant focus on developing biological treatments and a definitive in vivo diagnostic test for Alzheimer's disease. Promising avenues include: New drugs Neurosurgery (e.g., tissue implantation) Gene therapy The challenge lies in Alzheimer's being a diagnosis of exclusion, confirmed only at autopsy by identifying neurofibrillary tangles and plaques in the brain. Until such hallmark features can be detected in vivo, clinicians rely on probabilistic labels based on symptoms and biomarkers.

Question 34

What is the goal of "disease-modifying" medications for Alzheimer's disease, and what challenges are associated with them?

Answer 34

Disease-modifying medications aim to slow the progression of neurodegeneration by targeting brain shrinkage and the buildup of plaques and tangles associated with Alzheimer's. These medications seek to modify the disease rather than just manage symptoms. Challenges include: Determining whether these medications focus on symptom management or disease prevention. Patients desperate for new treatments may be eager to try these drugs, but they face risks if the medications are fast-tracked without sufficient testing.

Question 35

What controversy surrounded the approval of a new Alzheimer's medication, and what critical questions does it raise?

Answer 35

The controversy arose when a new Alzheimer's medication was fast-tracked for approval, bypassing some of the typical long-term research and testing required. This raised concerns within the research community about whether the drug's approval was premature. Critical questions include: Should research focus on improved cognition, behavior, reduced amyloid, or longevity? If medication effectiveness is limited, what alternative strategies can be used to support patients? How can the safety and efficacy of fast-tracked drugs be ensured without compromising patient care?

Question 36

What psychological interventions are recommended for people with dementia, and what challenges are associated with them?

Answer 36

Recommended psychological interventions include: Environmental changes: Supporting responses to changing cues to improve outcomes. Cognitive training and online games to prevent cognitive loss; however, research suggests these skills may not generalize to everyday function. Repeating instructions, simplifying environments, and removing distractions to create a more digestible cognitive world for individuals struggling with cognitive processing. Challenges: These interventions show limited promise in consistently improving day-to-day cognitive function, highlighting the need for personalized approaches.

Question 37

How can non-pharmacological strategies support caregivers and improve outcomes for people with NCDs?

Answer 37

Non-pharmacological strategies can: Alleviate caregiver burden by addressing BPSD symptoms through behavioral management strategies. Modify the environment to reduce challenging behaviors and enhance patient and caregiver wellbeing. Use environmental and behavioral management techniques as well-established therapeutic interventions to address behavioral issues in dementia patients. These approaches not only aim to manage patient symptoms but also provide crucial support to caregivers, improving the overall caregiving experience.

Question 38

What are some key challenges involved in conducting NCD research, and what factors should be considered in study design?

Answer 38

Conducting NCD research is challenging due to factors such as: Group types: Whether participants have comorbid conditions or "pure" disease. Dependent and independent variables: Determining what will change and how. Follow-up plans: Identifying who will conduct follow-ups and when. Outcome measurements: Ensuring they are both meaningful and sensitive. Ethics and consent: Managing vulnerabilities and ensuring ethical research practices. Consumer engagement: Involving patients and caregivers in research design. These considerations are essential for developing robust research protocols and ensuring participant well-being.

Question 39

What are the complexities surrounding the disclosure of an Alzheimer's disease (AD) diagnosis, and how can preferences be respected?

Answer 39

Disclosing an AD diagnosis involves several complexities: Anxiety and comprehension: Disclosure may increase anxiety or be difficult to understand, potentially worsening outcomes. Right to know: There are ethical questions about whether disclosure is always in the patient's best interest. Stage of disease: The timing of disclosure may impact its effectiveness and the patient’s response. Respecting preferences: Research shows people generally support knowing the diagnosis for both themselves and their loved ones. Preferences might change based on the availability of cures or treatments. A preliminary meeting can be used to explore individual preferences, ensuring they are honored during the diagnostic process.