Neurocognitive Disorders

Dr. Layali Abbasi Psychiatrist

Al-Balqa Applied University

5th year/Faculty of Medicine 2019-2010

Neurocognitive Disorders

• Delirium

• Dementia (Major Neurocognitive Disorder)

Delirium

• Delirium is characterized by an acute decline in both the level of consciousness and cognition with particular impairment in attention.

• A life threatening, yet potentially reversible disorder of the central nervous system (CNS), delirium often involves perceptual disturbances, abnormal psychomotor activity, and sleep cycle impairment.

• The major neurotransmitter hypothesized to be involved in delirium is acetylcholine.

• The major neuroanatomical area is the reticular formation.

• The EEG usually shows diffuse slowing of background activity, although patients with delirium caused by alcohol or sedative- -hypnotic withdrawal have low voltage fast activity.

Clinical features

• The hallmark symptom is an impairment of consciousness, usually occurring in association with global impairments of cognitive functions.

• Associated clinical features: -Disorganization of thought processes (ranging from mild tangentiality to frank incoherence). -Perceptual disturbances such as illusions and hallucinations. -Psychomotor hyperactivity and hypoactivity. -Disruption of the sleep-wake cycle (often manifested as fragmented sleep at night, with or without daytime drowsiness). -Mood alterations (from subtle irritability to obvious dysphoria, anxiety, or even euphoria).

• Sudden onset (hours to days).

• Brief duration (usually days to weeks).

• Fluctuating course, sometimes worse at night (sundowning).

• Rapid improvement when the causative factor is identified and eliminated.

Epidemiology

• Common disorder, with most incidence and prevalence rates reported in elderly adults.

• Advanced age is a major risk factor.

• Male gender is also an independent risk factor.

Predisposing factors for delirium

• Demographic characteristics: Age 65 years and older Male sex • Cognitive status Dementia Cognitive impairment History of delirium Depression • Sensory impairment Hearing Visual • Decreased oral intake • Drugs Treatment with psychoactive drugs Treatment with drugs with anticholinergic properties Alcohol use • Coexisting medical conditions

Precipitating factors for delirium

• Drugs Sedative-hypnotics Narcotics Anticholinergic drugs Alcohol or drug withdrawal • Primary neurologic diseases • Intercurrent illnesses infections dehydration • Surgery orthopedic surgery cardiac surgery • Environmental

Admission to ICU Use of physical restraints Pain

Course and prognosis

• Is a poor prognostic sign.

• The 3-month mortality rate of patients who have an episode of delirium is estimated to be 23-33%.

• The 1-year mortality rate of patients who have an episode of delirium maybe as high as 50%.

Treatment

• In treating delirium, the primary goal is to treat the underlying cause.

• Rooms should be kept well lit to minimize misperceptions; a room with a window can assist with day/ night orientation.

• Patients should be frequently reoriented to their surroundings-for example, clocks and calendars should be provided.

• Staff members should reintroduce themselves each time they visit.

Treatment

• Two major symptoms of delirium that may require pharmacological treatment are psychosis and insomnia.

• A commonly used drug for psychosis is haloperidol.

• Insomnia is best treated with benzodiazepines with short or intermediate half-lives (e.g., lorazepam).

Dementia (Major Neurocognitive Disorder)

• Dementia refers to a disease process marked by progressive cognitive impairment in clear consciousness.

Types of dementia based on etiology

• Alzheimer’s Disease

• Vascular dementia

• Frontotemporal Disorder

• Dementia of Lewy Bodies (DLB)

• Parkinson’s disease

• Traumatic brain injury

• Huntington’s disease

Epidemiology

• With the aging population, the prevalence of dementia is rising.

• The prevalence of moderate to severe dementia in different population groups is approximately 5 percent in the general population older than 65 years of age, 20 to 40 percent in the general population older than 85 years of age.

• Of all patients with dementia, (50 to 60 %) have the most common type of dementia, dementia of the Alzheimer’s type (Alzheimer’s disease).

• Vascular dementia is the second most common type of dementia, account for 15 to 30 percent of all dementia cases.

• Approximately (10 to 15%) of patients have coexisting vascular dementia and dementia of the Alzheimer’s type.

Reversible causes

• Approximately 15% of people with dementia have reversible illnesses if treatment is initiated before irreversible damage takes place.

• Reversible causes:

-Metabolic abnormalities (e.g., hypothyroidism)

-Nutritional deficiencies(e.g., vitamin B12, folate)

-Dementia syndrome caused by depression.

Dementia of the Alzheimer’s type

• The final diagnosis requires a neuropathological examination of the brain; nevertheless, is commonly diagnosed in the clinical setting after other causes of dementia have been excluded from diagnostic consideration.

Genetic factors

• 40% of patients have a family history of dementia of the Alzheimer’s type .

• Concordance rate for monozygotic twins is 43%.

• Has been shown linkage to chromosomes 1, 14 and 21.

• Amyloid precursor protein gene is on the long arm of chromosome 21.

• Multiple E4 genes:

-People with one copy of the gene have Alzheimer’s disease three times more frequently than do those with no E4 gene.

-People with two E4 genes have Alzheimer’s disease eight times more frequently than do those with no E4 gene.

Genetic factors

• 40% of patients have a family history of dementia of the Alzheimer’s type .

• Concordance rate for monozygotic twins is 43%.

• Has been shown linkage to chromosomes 1, 14 and 21.

• Amyloid precursor protein gene is on the long arm of chromosome 21.

• Multiple E4 genes:

-People with one copy of the gene have Alzheimer’s disease three times more frequently than do those with no E4 gene.

-People with two E4 genes have Alzheimer’s disease eight times more frequently than do those with no E4 gene.

Neuropathology

• Gross :Diffuse atrophy with flattened cortical sulci and enlarged cerebral ventricles.

• Microscopic: Senile plaques, neurofibrillary tangles, neuronal loss( particularly in the cortex and the hippocampus).

Neurotransmitters

• Hypoactivity of the acetylcholine and norepinephrine neurotransmitters .

Vascular Dementia

• Formerly referred to as multi-infarct dementia.

• The second most common type of dementia.

• Is causally related to cerebrovascular diseases.

• Account for (15 to 30%) of all dementia cases.

• More common in men than in women.

• Is more likely to show a decremental, stepwise deterioration than is Alzheimer’s disease.

Parkinson’s disease

• Although initially described exclusively as a movement disorder, Parkinson's disease (PD) is a neurodegenerative process affecting cognition, behavior, mood, and perception.

• Despite not being required for diagnosis, some nonmotor symptoms may be even more prevalent than the motor symptoms that define the disease; for example, anosmia and dysautonomia occur in 70% to 90% of patients, whereas up to one-third of patients with idiopathic PD do not experience resting tremors.

Parkinson’s disease

• Parkinson’s disease is a clinical diagnosis.

• Imaging and other tests are used to exclude confounding conditions.

Parkinson’s disease is a clinical

diagnosis.

Bradykinesia Rest tremor

Muscular rigidity Cogwheel rigidity

Postural instability (old criteria)

- Postural instability and frequent falling early is a red flag; if present, consider atypical parkinsonian syndromes.

- About 60 % t o 80 % of the dopamine cells in substania nigra are lost and this produces the clinical movement symptoms of Parkinson's disease.

+11

The prevalence of neuropsychiatric symptoms in Parkinson's disease

Neuropsychiatric condition

Prevalence

Mood disturbances

50%

Diagnosable anxiety disorder

30%

Dementia

80%

Nonmotor (extranigral) symptoms

-Subcortical nuclei

-Limbic regions

-Neocortex

Misfolded alpha-synuclein

And lewy bodies

Cognitive impairment

Parkinson's disease Braak staging model

Stage Structure Clinical symptom

1 Olfactory nerve Hyposmia Anosmia

2 Locus coeruleus Raphe nuclei

REM sleep behavior disorder Depression Anxiety

3 Substania nigra Bradykinesia Rigidity Tremor

Psychiatric Disturbances in Parkinson’s Disease

• Anxiety and depression can occur at any stage of Parkinson's disease (PD) but have a peak incidence around the time of diagnosis.

• Peak incidence of neuropsychiatric symptoms at the time of PD diagnosis likely occurs due to a combination of biological (e.g., PD), psychological (e.g., stress reactions to diagnosis and disability), and social (e.g., altered social roles and relationships) factors.

Psychiatric Disturbances in Parkinson’s Disease

• Psychosis in Parkinson's disease is associated with dopamine replacement therapy and cognitive impairment and is more common in advanced disease.

• Visual hallucinations are the most common symptom of Parkinson's disease psychosis.

Frontotemporal lobar degeneration (FTLD)

• Has insidious onset and gradual progression. • Language-varient FTLD • Behavioral-varient FTLD -The most common presentation of FTLD.. -Characterized by progressive changes in personality and behavior, as well as cognitive dysfunction.

Frontotemporal Disorder (Pick’s Disease)

• Constitutes approximately 5% of all irreversible dementias.

• Is most common in men.

• Early stages are more often characterized by personality and behavioral changes, with relative preservation of other cognitive functions.

• Approximately half of all cases are familial.

Lewy Body Disease

Core features: Fluctuating levels of attention and alertness. Recurrent visual hallucinations. Parkinsonian features (cogwheeling, bradykinesia, and resting tremor) arising after cognitive impairment. Supporting features: Repeated falls Syncope Sensitivity to neuroleptics Systematized delusions Hallucinations in other modalities (e.g. auditory, tactile)

Lewy Body Disease

• Functional brain imaging frequently shows low blood flow or low metabolic activity in the occipital lobes.

• Low dopamine transporter uptake in basal ganglia is a diagnostic marker.

Diagnosis and clinical features

• Memory impairment is typically an early and prominent feature in dementia.

• Early in the course , memory impairment is mild and usually most marked for recent events; people forget telephone numbers, conversations, and events of the day.

• As the course of dementia progresses, memory impairment becomes severe, and only the earliest learned information (e.g., a person’s place of birth) is retained.

Psychiatric and neurological changes

• Personality: -Patients with dementia may also become introverted and seem to be less concerned than they previously were about the effects of their behavior on others. -Persons with dementia who have paranoid delusions are generally hostile to family members and caretakers. -Patients with frontal and temporal involvement are likely to have marked personality changes and may be irritable and explosive.

• Hallucinations and delusions: -An estimated (20 to 30 %) of patients with dementia (primarily patients with dementia of the Alzheimer’s type) have hallucinations, and (30 to 40 %) have delusions, primarily of a paranoid or persecutory nature. -Physical aggression and other forms of violence are common in demented patients who also have psychotic symptoms.

• Mood:

-Depression and anxiety are major symptoms in an estimated (40 to 50 %) of patients with dementia, although the full syndrome of depressive disorder may be present in (only 10 to 20 %).

-Patients with dementia also may exhibit pathological laughter or crying-that is, extremes of emotions-with no apparent provocation.

Delirium Depression Alzheimer’s Dementia

Onset Abrupt Relatively discrete Insidious

Initial symptoms Difficulty with attention and disturbed consciousness

Dysphoric mood or lack of pleasure

Memory deficits: verbal or spatial

Timeline Fluctuating over days to weeks

Persistent, usually lasting months

Gradually progressive over years

Family History Not contributory May be positive for depression

May be positive for Alzheimer’s dementia

Memory Poor registration Patchy or inconsistent loss of memory

Short-term memory worse than long- term memory

Subjective memory complaints

Absent Present Variable; usually absent

Example of language deficit

Difficulty attending to conversation or written tasks

Increased speech latency

Difficulty with naming objects

Affect Often labile Depressed or irritable Can vary; may be neutral

THE END