Dementia
Dementia is a Neuro-degenerative disorder of progressive cognitive impairment, where various cognitive skills like attention, concentration, memory, emotional balance, thought, speech, executive functions, social cognition & motor skills are lost progressively.
Major types are:
Alzheimer’s disease, dementia of Lewy bodies, vascular dementia, frontotemporal dementia & Parkinson’s disease dementia.
As the age advances, the prevalence of dementia also increases. The prevalence of moderate to severe dementia is 5% in people older than 65 years of age, 20 to 40% in older than 85 years of age.
MAJOR TYPES OF DEMENTIAS
1. Alzheimer’s Dementia
Neuropathology: The brain of a patient with Alzheimer’s disease will have diffuse atrophy (decrease in size) with flattened cortical sulci and enlarged cerebral ventricles (fluid filled spaces in the brain). The classic and pathognomonic microscopic findings are senile plaques, neurofibrillary tangles, neuronal loss (particularly in the cortex and the hippocampus), synaptic loss (perhaps as much as 50 percent in the cortex), and granulo-vascular degeneration of the neurons.
Neurotransmitters: The neurotransmitters that are most often implicated in the Alzheimer’s disease are acetylcholine and norepinephrine, both of which are hypoactive (decreased) in Alzheimer’s disease.
2. Lewy Body Dementia
Lewy body dementia is characterised by fluctuating cognition, attention & alertness, with recurrent well-formed hallucinations. Parkinsonian symptoms like masked facies, rigidity, tremors & recurrent falls may be seen later in the course of the disease. There will be high sensitivity and side effects to anti-psychotic medications. Lewy inclusion bodies are found in the cerebral cortex.
3. Vascular Dementia
In vascular dementia, blood vessels carrying blood to the brain (arteries) will develop blocks & hence that brain area will get damaged as it doesnt get the required nutrients & oxygen. This block can happen to big arteries as in a major stroke or can happen to multiple small arteries when the. So, there will be a decremental stepwise deterioration in cognitive functions following each stroke. The symptoms depend on the particular blood vessels affected & the areas of the brain involved. But attention & executive functions are commonly involved.
4. Fronto-Temporal Dementia (Pick’s Disease)
It is characterized by a preponderance of atrophy (wasting) in the frontotemporal regions of the brain. These regions also have neuronal loss; gliosis; and neuronal Pick’s bodies. It constitutes 5% of all irreversible dementias. It typically begins before 75yrs of age. The early stages are characterised by personality & behavioural changes than memory impairment.
5. Parkinson’s Disease Dementia
20 – 30 % of patients with Parkinson’s disease have dementia. Dementia develops years after the development of Parkinson’s disease. Slowed movements, slowed speech, difficulty walking, rigid postures, masked facies are seen along with dementia symptoms.
DIAGNOSIS AND CLINICAL FEATURES
The diagnosis of dementia is based on the clinical examination, including a mental status examination, and on information from the patient’s family & friends. Complaints of a personality change in a patient older than age 40 years suggest that a diagnosis of dementia should be carefully considered. Patient’s complaints about intellectual impairment and forgetfulness as well as evidence of patients’ evasion, denial, or rationalization aimed at concealing cognitive deficits may be seen. Excessive orderliness, social withdrawal, or a tendency to relate events in minute detail can be characteristic, and sudden outbursts of anger or sarcasm can occur. Lability of emotions; sloppy grooming; uninhibited remarks; silly jokes; or a dull, apathetic, or vacuous facial expression and manner suggest the presence of dementia, especially when coupled with memory impairment. Memory impairment is typically an early and prominent feature in dementia, especially in dementias involving the cortex, such as dementia of the Alzheimer’s type. Early in the course of dementia, memory impairment is mild and usually most marked for recent events; people forget 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. Patients with dementia may forget how to get back to their rooms after going to the bathroom.
Dementing processes that affect the cortex, primarily dementia of the Alzheimer’s type and
vascular dementia, can affect patient’s language abilities.
Psychiatric and Neurological Changes
Personality: Changes in the personality of a person with dementia are especially disturbing for their families. 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 (suspiciousness) 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: About 20 – 30 % of patients with dementia have hallucinations, and 30 – 40 % have delusions, primarily of a paranoid or persecutory and unsystematized nature. Physical aggression and other forms of violence are common in demented patients who also have psychotic symptoms.
Mood: In addition to psychosis and personality changes, depression and anxiety are major symptoms in an estimated 40 to 50 percent of patients with dementia, although the full syndrome of depressive disorder may be present in only 10 to 20 percent. Patients with dementia also may exhibit pathological laughter or crying – that is, extremes of emotions – with no apparent provocation.
Cognitive Change: In addition to the aphasias (difficulty in talking/ understanding others speech) in patients with dementia, apraxias (inability to perform learned movements like combing hair) and agnosias (ability to recognize objects, faces) are common. Seizures are seen in approximately 10 % of patients with dementia of the Alzheimer’s type and in 20 % of patients with vascular dementia. Primitive reflexes may be present on neurological examination, and myoclonic jerks are present in 5 to 10 % of patients.
Catastrophic Reaction: Patients with dementia have difficulty generalizing from a single instance, forming concepts, and grasping similarities and differences among concepts. Furthermore, the ability to solve problems, to reason logically, and to make sound judgments is compromised. Catastrophic reaction marked by agitation secondary to the subjective awareness of intellectual deficits under stressful circumstances is seen.
Lack of judgment and poor impulse control appear commonly. Impairments like coarse language, inappropriate jokes, neglect of personal appearance and hygiene, and a general disregard for the conventional rules of social conduct may be seen.
Sundowner Syndrome: In Dementia patients, symptoms get worse after sunset. This, known as Sundowner syndrome is characterized by drowsiness, confusion, imbalance, and accidental falls. The syndrome also occurs in demented patients when external stimuli, such as light and interpersonal orienting cues, are diminished.
Laboratory Investigations
• MRI/CT Scan to confirm & differentiate between different Dementia sub-types. Also helps in ruling out other causes which may mimic a dementia picture.
• TFT- Thyroid blood test to rule out hypothyroidism – which is a treatable cause of dementia.
• Vitamin blood levels – B12, vitD3 – which may cause secondary treatable Dementias
• Screening for HIV, VDRL – which may cause Dementias
• Blood & Urine Routines – to rule out systemic & urinary infections which maycomplicate Dementias
• LFT & RFT – to look for other systemic causes
COURSE AND PROGNOSIS
The classic course of dementia is onset in the patient’s 60s, with gradual deterioration over 5 to 10 years, leading eventually to death. The age of onset and the rapidity of deterioration vary among different types of dementia. The average survival expectation for patients with dementia of the Alzheimer type is approximately 8 years, with a range of 1 to 20 years. Data suggest that in persons with an early onset of dementia or with a family history of dementia, the disease is likely to have a rapid course. After diagnosing dementia, patients must have a complete medical and neurologic workup because 10 to 15 percent of all patients with dementia have a potentially reversible condition if we initiate treatment before permanent brain damage occurs. Although the symptoms of the early phase of dementia are subtle, they become conspicuous as dementia progresses, and family members may then bring a patient to a physician’s attention. In the terminal stages of dementia, patients become empty shells of their former selves—profoundly disoriented, incoherent, amnestic, and incontinent of urine and faeces.
TREATMENT
Psychosocial Therapies
The deterioration of mental faculties has significant psychological meaning for patients with dementia. The experience of a sense of continuity over time depends on memory. Patients lose recent memory before remote memory in most cases of dementia, and many patientsare profoundly distressed by clearly recalling how they used to function while observing their noticeable deterioration. At the most fundamental level, the self is a product of brain functioning. Patients’ identities begin to fade as the illness progresses, and they can recall less and less of their past. Emotional reactions ranging from depression to severe anxiety to catastrophic terror can stem from the realization that the sense of self is disappearing. Patients often benefit from supportive and educational psychotherapy in which the clinician clearly explains the nature and course of their illness. They may also benefit from assistance in grieving and accepting the extent of their disability and from attention to self-esteem issues. We should try to maximize any areas of intact functioning by helping patients identify activities in which successful functioning is possible.
Clinicians can help patients find ways to deal with the defective functions, such as keeping calendars for orientation problems, making schedules to help structure activities, and taking notes for memory problems. Psychodynamic interventions with family members of patients with dementia may be of great assistance. Those who take care of a patient struggle with feelings of guilt, grief, anger, and exhaustion as they watch a family member gradually deteriorate. A common problem that develops among caregivers involves their self-sacrifice in caring for a patient. They often suppress any developing resentment from this selfsacrifice because of the guilt feelings it produces. Clinicians can help caregivers understand the complex mixture of feelings associated with seeing a loved one decline and can provide understanding as well as permission to express these feelings.
Pharmacotherapy
Psychiatrists may prescribe sedative-hypnotics for insomnia and anxiety, antidepressants for
depression, and antipsychotic drugs for delusions and hallucinations. The medicinesDonepezil, rivastigmine, galantamine, and tacrine are cholinesterase inhibitors used to treat
mild to moderate cognitive impairment in Alzheimer disease. They reduce the inactivation
of the neurotransmitter acetylcholine and thus potentiate the cholinergic neurotransmitter,
which in turn produces a modest improvement in memory and goal-directed thought. These
drugs are most useful for persons with mild to moderate memory loss who have sufficient
preservation of their basal forebrain cholinergic neurons to benefit from augmentation of
cholinergic neurotransmission. The medicine- Memantine protects neurons from excessive
amounts of glutamate, which may be neurotoxic. Sometimes we Psychiatrists combine
memantine with donepezil.
A variety of other interventions including cognitive stimulation, music therapy, omega 3 fish
oil, statins, ginkgo biloba, aromatherapy, or nonsteroidal anti-inflammatory drugs can be
tried. Exercise improves cognition in healthy adults, and there is some evidence of benefit in
dementia, particularly in the early stages.
Reference :
1. Oxford Textbook of Psychiatry
2. Kaplan & Sadock’s Comprehensive Textbook of Psychiatry
3. The ICD-10: Classification of Mental and Behavioural Disorders
4. Diagnostic and Statistical Manual of Mental Disorders (DSM–5)
5. https://www.ncbi.nlm.nih.gov/pmc/
Self-Assessment
