Neurocognitive Disorders (NCDs)

Neurocognitive Disorders (NCDs)

• NCDs are conditions marked by a significant decline in cognitive abilities, such as thinking, memory and reasoning
• This decline is relative to an individual's prior level of cognitive functioning
• The DSM-IV-TR referred to these disorders as Dementia, Delirium, Amnestic, and Other Cognitive Disorders
• The DSM-5-TR groups these conditions as NCDs, which can be further classified

Classifications of NCDs

• Delirium involves acute confusion and disorientation
• Major NCD includes significant cognitive decline, previously known as dementia
• Minor NCD is a mild cognitive decline, also known as mild cognitive impairment (MCI)
• NCDs are specified further based on the underlying cause, such as Alzheimer's or Parkinson's disease

Clinical Findings and Course of Delirium

• Delirium is defined by a sudden disturbance in attention, awareness, and cognitive function

Signs and Symptoms of Delirium

• Individuals struggle to maintain and shift their focus
• Individuals are easily distracted and need constant reminders to pay attention
• Disorganized thinking and speech leads to rambling, irrelevant, pressured, and incoherent speech
• Reasoning skills and ability to engage in goal-oriented behavior are diminished
• Disorientation to time and place is typical, and recent memory is often impaired
• Perception changes include misperceptions of the environment with illusions or hallucinations
• Normal sleep-wake cycle is disturbed
• Awareness levels vary from hypervigilance to stupor or semi-coma
• Sleep patterns fluctuate between hypersomnolence and insomnia
• Vivid dreams and nightmares are also common
• Psychomotor activity fluctuates between agitation with purposeless movements, and a vegetative state resembling catatonic stupor
• Tremors are frequently observed
• Rapid shifts in emotions can occur like fear, anxiety, depression, irritability, anger, euphoria, or apathy
• Emotions can manifest as crying, cursing, moaning, self-destructive acts, attempts to flee, or aggression
• Autonomic nervous system changes include rapid heart rate, sweating, flushed face, dilated pupils, and elevated blood pressure

Onset, Duration, and Resolution of Delirium

• Delirium symptoms typically start suddenly after a head injury or seizure
• Delirium may be preceded by hours or days of prodromal symptoms like restlessness, difficulty thinking, insomnia, or excessive sleepiness
• Slower onset is likely when caused by systemic illness or metabolic imbalance
• Usually brief, lasting about a week, and rarely more than a month
• Symptoms typically subside within 3 to 7 days after addressing the underlying cause, but resolution can take up to 2 weeks in some cases
• A person's age and the duration of the delirium can affect how quickly symptoms resolve
• Delirium is associated with a high mortality rate due to the severity of the underlying medical conditions causing it
• Delirium can sometimes transition into a more permanent neurocognitive disorder (NCD)

Predisposing and Precipitating Factors for Delirium

• Predisposing factors are conditions that make individuals more susceptible to developing delirium
• These include serious medical, surgical, or neurological conditions, older age (65+), depression, falls and elder abuse
• Precipitating factors are triggers that can directly lead to an episode of delirium in vulnerable individuals
• These are systemic infections, febrile illness or hyperthermia, metabolic disorders, hypoxia (low oxygen levels) and COPD, hepatic or renal failure
• Other triggers are head trauma, seizures, migraine headaches, brain abscesses, stroke, nutritional deficiency, uncontrolled pain, burns, heat stroke etc.

Delirium Related to Substance Use

• Substance Intoxication Delirium is caused by toxic effects of substances on the brain, including alcohol, amphetamines, cannabis, cocaine, hallucinogens, inhalants, and opioids
• Substance Withdrawal Delirium occurs when someone abruptly stops using certain substances after prolonged use, common ones include alcohol and opioids

Medication-Induced Delirium

• Certain medications can trigger delirium as a side effect
• Common medications include Anticholinergics, Antihypertensives, Corticosteroids, Anticonvulsants, Cardiac glycosides, Analgesics, Anesthetics, Antineoplastic agents and Antiparkinson drugs
• Other medications include H2-receptor antagonists (e.g., cimetidine)
• Polypharmacy, taking multiple medications at the same time, also increases the risk

Delirium Due to Other Medical Conditions or Multiple Etiologies

• Can be caused by an underlying medical condition or a combination of factors
• Urinary tract infections (UTIs) are strongly linked to delirium, especially in older adults(65+)
• Increased levels of interleukin-6 (a marker of inflammation) might contribute
• Often the result of multiple combined factors rather than a single cause

Neurocognitive Disorder (NCD) Classification

• NCDs are classified based on the DSM-5-TR, according to symptom severity
• Mild NCD is sometimes referred to as mild cognitive impairment (MCI), and early intervention is key
• Major NCD encompasses what was previously known as dementia in the DSM-IV-TR
• These diagnoses (mild and major NCD) can represent different stages of the same condition in progressive neurodegenerative conditions

Defining Dementia/Major NCD

• Dementia (major neurocognitive disorder) is a decline in cognitive functions (memory, thinking, decision-making)
• This decline is severe enough to interfere with social, behavioral, occupational, and emotional functioning

Gradual Progression and Reversibility

• Unlike delirium, which has a rapid onset, dementia develops gradually
• Dementia can sometimes be reversible, depending on the underlying cause

Alzheimer's Disease (AD)

• Approximately 6.5 million people in the United States have Alzheimer's disease (AD)
• It is the most prevalent form of neurocognitive disorder (NCD)
• The number of people with AD increases significantly with age

AD Prevalence by Age

• 5% of individuals between 65 and 74 years old
• 13.1% of individuals between 75 and 84 years old
• 33.2% of individuals 85 years and older
• Most (80%) with AD are over 75, although some are under 65
• Increasing age is the biggest risk factor for AD, but aging itself is not a normal part of it

AD: Gender and Race

• Almost two-thirds of Americans with AD are women
• Higher prevalence in Black/African American and Hispanic/Latino people than among non-Hispanic White people
• More research is needed to understand the risk factors for AD in these populations

AD Projected Increase and Survival

• By 2050, the number of people aged 65 and older with Alzheimer's dementia is projected to reach 12.7 million
• Increase in AD is due to the growing population of older adults rather than an epidemic
• After being diagnosed, people typically live for 4 to 8 years, spending most of that time in the most severe stage Some individuals may live as long as 20 years

Recent Trends in AD

• Recent studies suggest dementia, including newly developing AD cases, has been declining in the United States
• May be due to improved treatment and awareness of risk factors for heart disease and stroke

Mild and Major Neurocognitive Disorders (NCDs) Explained

• NCDs are characterized by a decline in cognitive functions, classified by the degree to which these deficits affect daily living
• Cognitive decline is determined from a prior level of cognitive ability in one or more cognitive areas
• These include: complex attention, executive function, learning and memory, language, perceptual-motor and social cognition

Mild Neurocognitive Disorder Defined

• There is modest cognitive decline from a previous level of performance
• Cognitive deficits do not interfere with independence in everyday activities, although greater effort or accommodation may be required

Etiologies for Mild And Major NCDs

• Substance/medication use, HIV infection, prion disease, Parkinson's disease, Huntington's disease, another medical condition, multiple etiologies and unknown etiology

NCDs and Behavioral Disturbances

• If the cognitive decline occurs without significant behavioral or psychological symptoms, the NCD is classified as being "without behavioral disturbance"
• With Behavioral Disturbance: If the cognitive decline is accompanied by clinically significant behavioral or psychological symptoms, then the NCD is classified as being ''with behavioral disturbance"
• Examples of behavioral disturbances include psychotic symptoms, mood disturbances, agitation, apathy, aggression, disruptive behaviors, or sleep/appetite disturbances

NCD Diagnostic Criteria

• Key criterion is evidence of significant cognitive decline from a previous level of performance
• Decline should be based on: concern from the individual, informant and clinician

Cognitive and Behavioral Changes in NCD

• Impaired Thinking: Abstract thinking, judgment, and impulse control are impaired
• Social Disregard: Individuals may disregard social norms, possibly exhibiting uninhibited or inappropriate behavior
• Neglect of Hygiene: Personal appearance and hygiene are often neglected
• Language Difficulties: Language can be affected, with difficult naming objects or vague and imprecise speech
• Personality Changes: Personality changes are common

Reversibility and Progression of NCDs

• True reversibility is rare and may be more accurately described as temporary
• Reversible causes include brain tumors, subdural hematomas, vitamin deficiencies, poisoning, CNS infections and thyroid disorders
• Irreversible NCD: In most cases, NCD is progressive and irreversible

Later-Stage Symptoms and Complications of NCDs

Apraxia: Inability to perform purposeful motor acts despite intact motor function occurs.

• Emotional Changes: Common symptoms involve Irritability, moodiness, and sudden outbursts
• Loss of Independence occurs, diminishing an ability to work or manage personal care
• Concerns about Wandering: Wandering away from home or care settings increases
• Advanced Dementia: Includes profound memory deficits, minimal verbal communication, loss of ability and incontinence.
• Common complications include eating problems and infections

Causes of NCD

• Alzheimer's Disease (AD) is the most common accounting for 60-80% of all cases

Five Stages of AD

• Stage 1: Preclinical AD features no noticeable symptoms or decline in memory
• Brain changes are detectable through PET scans; however, these changes do not always lead to progressive disease
• Stage 2: MCI due to AD (Mild Cognitive Impairment) includes subtle symptoms
• Symptoms such as memory loss and language and thinking problems that may be noticeable to the individual, family, and friends, but not readily apparent to others.
• The brain can no longer compensate for neuron damage and death
• Stage 3: Mild Dementia due to AD features that individuals can function independently in many areas but need assistance with more complex tasks
  • Individuals may deny problems and cover up memory loss by creating imaginary events to fill in memory gaps (confabulation)
• Stage 4: Moderate Dementia due to AD is often the longest stages and interferes with completing activities of daily living (ADLs)
• Symptoms worsen in their recognition of loved ones and are often worsen as "sundowning" in the late afternoon or evening
• Stage 5: Severe Dementia due to AD includes that symptoms interfere with most everyday activities
• Loss of interest in food and inability to recognize family members

More Late-Stage AD Symptoms

• Sufferers require 24-hour care and exhibit greatly diminished ability to communicate and swallow
• Also comes with an Increased risk of bedsores, contractures, blood clots, aspiration pneumonia, infections, sepsis, and death

NCD Etiology and Categories

• Classified and distinguished based on their underlying cause
• Includes AD, Frontotemporal degeneration, Lewy body disease, Vascular disease, and Traumatic brain injury
• Another etiology is caused by Substance/medication use, HIV infection, Prion disease, Parkinson's disease and Huntington's disease

Neurocognitive Disorder and Alzheimer's Disease

• Diagnosed with the symptoms and manifests with either mild or major progression through each stage

Alzheimer's Disease Pathophysiology

• Marked by a gradual and subtle onset that results in memory impairment
• Diagnosed with Refined diagnostic criteria and tools that helps clinicians
• CT and MRI scans may reveal degenerative changes, atrophy, widened cortical sulci, and enlarged cerebral ventricles
• Microscopic examination reveals neurofibrillary tangles and senile plaques that may be concentrated in the hippocampus and cerebral cortex
• Recent research has highlighted mutations in MARK4 contribute to protein of cells and may lead to neurodegeneration as well
• Many factors: Development and progression of AD likely involves a series of combining factors in those affected