COGNITIVE AND
AFFECTIVE DISORDERS IN THE ELDERLY
Márta Balaskó and Gyula Bakó
Molecular and Clinical Basics of Gerontology – Lecture 18
Medical Biotechnology Master's Programmes
at the University of Pécs and at the University of Debrecen
Identification number: TÁMOP-4.1.2-08/1/A-2009-0011
necessarily deteriorate.
Various cognitive functions decline, while others improve:
• Activity requiring quick reactions and or high degree precision grow weaker.
• Decrease in speed of processing, working memory, inhibitory function and long-term memory are seen.
• Wise consideration based on experience, the ability to
understand and learn from new experience is maintained.
Aging-associated cognitive, affective and psychiatric disorders (outline)
• Dementia
- Neurodegenerative disorders leading to dementia (Alzheimer’s disease)
- Non-Alzheimer dementias (vascular dementia, organic brain disorders)
- Delirium
- Amnestic syndromes
• Alcohol abuse and consequences
• Affective disorders: depression
A serious loss of cognitive ability with maintained vigilance.
Dementia is a clinical diagnosis.
Impairments affect:
• memory (disturbed recognition: agnosia),
• speech (aphasia), language,
• judgement,
• emotional control,
• behavior,
• attention ,
• abstract thinking,
• executive functions (apraxia),
that causes disruption in relationships and social functions.
Dementia: prevalence and most frequent forms
Prevalence
It affects 1% of population at the age of 60, prevalence doubles every year.
It reaches 10 % at 65 years, and 35% above 90 years.
Most prevalent dementias
• Senile dementia of the Alzheimer type (Alzheimer’s disease) 60%
• Non-Alzheimer dementias (organic brain disorders)
• Delirium
• Amnestic syndromes
A (premature) progressive age-associated loss of cognitive
functions (in middle-aged and older) also involving affective and behavioral disturbances.
Risk factors
• age 65 years
• female gender
• low education level (primary school drop-outs: 2× risk)
• positive family anamnesis: 4× risk
• head trauma: 2× risk
• smoking, metabolic syndrome X, atrial fibrillation, stroke, alcohol consumption, genetic predisposition
Prevalence of Alzheimer’s disease
0 10 20 30 40 50 60
60-64 65-69 70-74 75-79 80-84 85+ 95+
Prevalence (%)
Age (years)
1% 2% 4%
8%
16%
30%
50%
Loss of neurons, synapses and atrophy in the cerebral cortex and certain subcortical regions (temporal and parietal lobes, parts of the frontal cortex)
Pathogenesis
cholinergic theory: reduced synthesis of the acetylcholine beta-amyloid: dense and insoluble deposits of amyloid beta precursor protein (APP) fragments form senile plaques around neurons initiating damage
tau protein misfolding : intracellular neurofibrillary tangles cause microtubules to disintegrate, damaging the neuron’s transport system
Inflammation, oxidative stress, accumulation of aluminium in brain, etc.
Senile dementia of the Alzheimer type (SDAT, Alzheimer’s disease) 3
Phases
1 Mild cognitive impairment, preclinical stage
a gradual, hidden, progressive onset may last for 7-8 years symptoms (memory loss) are mistaken for stress and aging 2 Early stage
increasing forgetfulness, difficulties with language, executive functions, agnosia, apraxia, personality changes
3 Moderate stage
dependency increases
difficulty with speech, pathological behavior (agression) and confusion, delusions
4 Advanced stage
complete dependency, verbal output decreases, pronounced memory decline, patients get bed-ridden, death
Average survival is 7 years. Most common causes of death:
pressure ulcers, pneumonia
Treatment
No drug has been shown to cure the disease or delay progression.
Some drugs alleviate symptoms:
• acetylcholinesterase inhibitors
• glutamate NMDA receptor antagonist
A safe, emotionally supportive environment, physical exercise, optimal diet may improve quality of life of the patient.
Non-Alzheimer dementias (organic brain disorders)
Characteristics
• Symptoms may resemble those of Alzheimer’s disease
• Onset is usually different, changes may occur suddenly or they may not be progressive over time
• In case of metabolic or infectious causes progression may be stopped, even some alleviation of the symptoms is possible.
Degenerative disorders Parkinson’s, Pick, Lewy Huntington
Vascular, post-stroke states Space occupying lesions Post-trauma states
polytrauma (boxing, liver) subdural hematoma,
hemodialysis
Infectious agents
AIDS, prion (Creutzfeldt- Jakob),
neurosyphilis, Lyme disease meningitis
Poisons
alcohol, drugs, medications CO poisoning
Genetic, metabolic causes Wilson’s, hypoglycemias Organ failures
Tumor, metastases failure, renal failure, hydrocephalus heart failure,
thyroid disorders Deficiencies
vitamin B12-, folic acid-, niacin deficiency
Delirium: definition
Characteristics
• It is a clinical syndrome characterized by inattention and acute severe (reversible) cognitive dysfunctions
• In the young, high fever, severe alcohol intoxication, severe metabolic disturbances, etc. may cause delirium
• In the elderly, functional reserve capacity of the brain declines , therefore many milder disorders may lead to delirium
• Delirium affects 14–56% of all hospitalized elderly patients.
Postoperative delirium occurs in 15–53% of surgical
patients over 65 years, and 70–87% among elderly patients admitted to intensive care units.
• Dementia or cognitive impairment
• History of delirium, stroke, neurological disease, falls
• Multiple comorbidities
• Male gender
• Chronic renal or hepatic disease
• Sensory impairment (hearing or vision)
• Immobilization (restraint, catheters)
• Medications (sedative hypnotics, narcotics, anticholinergic, drugs, corticosteroids, polypharmacy, alcohol or drug
withdrawal)
• Acute neurological diseases [acute stroke (usually right parietal), meningitis, encephalitis]
Delirium in the elderly: risk factors 2
Risk factors
• Intercurrent illness
(minor infections, iatrogenic complications, anemia, ordinary volume loss, poor nutrition, fracture, trauma)
• Metabolic derangement
severe hypoglycemia, hyper- or hypotonicity
• Surgery
• Alarming environment
(e.g. admission to an intensive care unit)
• Pain
• Emotional distress
• Sustained sleep deprivation
Memory functions are disproportionately impaired compared to other cognitive functions in an otherwise alert patient.
The patient can not remember recent events or learn simple tasks, while performing complex tasks learned previously.
Most common forms
• Wernicke-Korsakoff Syndrome
chronic alcoholism, chronic thiamine deficiency
• Transient Amnestic Syndromes
transient cerebral ischemia, migraine, alcohol intoxication (“blackouts”), drugs (e.g. benzodiazepines, barbiturates, ketamine), head injury (concussion)
• Psychogenic amnesia
posttraumatic stress disorder
Alcohol abuse and consequences in the elderly
Prevalence
Alcohol abuse and alcoholism are prevalent and under-recognized problems in the elderly. About 6 percent of older adults are
considered heavy users of alcohol (13% of men, 2% of women).
The majority of older alcoholic persons (around 66%) grow older with early-onset alcoholism, about 34% develop a problem with alcohol in later life.
Age-related alterations in pharmacokinetics of alcohol
• Gastrointestinal absorption is comparable, distribution is diminished due to decrease in fat free mass.
• Liver perfusion and metabolism in the liver declines slightly.
higher peak serum alcohol
Alcohol-induced alterations in drug metabolism:
• acute competitive inhibition of drug metabolism involving the cytochrome P450 system (microsomal ethanol oxidizing
system=MEOS), e.g. narcotics, tranquillizers leading to suppression of respiratory center
• chronic upregulation of the cytochrome P450 system enhancing clearance of drugs, e.g. coumarins
Falls may be precipitated by alcohol due to acute ataxia, acute hypotension (vasodilatory and diuretic effect), chronic myopathy, cerebellar atrophy and peripheral neuropathy. These falls may lead to hip fractures!
Moderate drinking may exacerbate hypertension, and heavy
drinking increases the risk of stroke. Arrhythmia may develop after an alcohol binge.
Consequences of alcohol abuse in the elderly 2
Consequences
Ischemic heart disease is responsible for more cardiac deaths among older alcoholics than alcohol-induced cardiomyopathy.
Gastrointestinal bleeding are common among older alcoholics.
The liver is more susceptible for alcoholic hepatitis, fatty liver or cirrhosis in old individuals. About 50% of elderly patients with cirrhosis die within one year of diagnosis.
Elderly patients are more prone to alcohol or its withdrawal-induced delirium .
Chronic alcoholism lead to Wernicke encephalopathy (an acute state of confusion, ataxia and abnormal eye movements) and Korsakoff’s syndrome (an isolated memory deficit manifesting in
confabulation). Global cognitive impairment and alcohol-related dementia based on profound cerebral atrophy is more common in elderly alcoholics.
Depression is a state of low mood and aversion to activity. It may can affect the thoughts, feelings, behavior, and physical well-being of the patient. It usually involves feelings of
sadness, anxiety, emptiness, hopelessness, worthlessness, guilt, irritability or restlessness.
The prevalence of depression among the elderly is increasing.
Their treatment presents a big strain on society.
Depression in the elderly is seldom properly diagnosed. It does not receive proper attention.
Depression in the elderly:
risk factors
It is strongly influenced by such risk factors that become more common with aging:
• genetic factors determine susceptibility for depression
• neurological changes,
• multimorbidity, pain,
• impaired function of sensory organs
• loneliness, isolation
• personal crises, bereavement, anxiety
• reduced adaptability
• lack of perspectives in life, lack of motivation,
• decreased ability to work,
• loss of family background, deficiencies of education, poor social network, negative effects of retirement.
• There is an overlap between the normal phenomena of aging and signs of depression.
• Clinical characteristics may be misleading. Symptoms may be suppressed, non-characteristic or associated with somatization
(complaining about unreal somatic symptoms) and agitation/anxiety.
• It may occur (in a hardly discernible way) in association with chronic diseases and organic cerebral disorders.
Characteristics associated with the patient:
• Losses, bereavement, isolation, shame, refusal of treatment.
• Neither the patient nor the relatives hope for any improvement with the treatment.
Characteristics of health professionals:
• Misconceptions related to old age, lack of empathy and attention.
Depression: prognosis
Poor prognosis, danger signs of suicide:
• advanced age at the onset of depression,
• presence of anxiety in past medical history,
• personality disorders,
• alcohol abuse,
• psychotic signs,
• cognitive impairment,
• organic cerebral disorders, loneliness, poor social circumstances,
• delayed treatment, inadequate management
• keeps complaining
• communicates in detail
• “I don’t know”
• does not want to do
• does not complain
• poor communication
• replies with mistakes
• eager to cooperate