Sreeja V, RN,BSN, DPN*

Outline

• Introduction
• Etiology
• Epidemiology
• Sign & Symptoms
• Types of Dementia
• Assessment & Management
• Nursing Management
• Nursing care plan
• Problems of the carer
• Pre and Post Test
• Bibliography
• Glossary

II. ETIOLOGY OF DEMENTIA

Dementia has many causes, but Dementia of the Alzheimer’s type and vascular dementia together represent as many as 75 percent of all cases. Other causes of dementia are Pick’s disease. Creutzfeldt Jakob disease. Huntington’s disease, Parkinson’s disease, Human Immunodeficiency Virus (HIV) and Head trauma.

CAUSES OF DEMENTIA

A. Degenerative diseases of the central Nervous System.

• Senile dementia
  
• Alzheimer’s disease
  
• Pick’s disease
  
• Huntington’s chorea
  
• Parkinson’s disease
  
• Creutzfeldt Jakob disease
  
• Normal pressure hydrocephalus
  
• Multiple sclerosis
  
• Lewy body disease

B. Intra Cranial Causes

• Space – occupying lesions
• Tumors
• chronic subdural haematomas
• chronic abscesses
• aneurysm

C. Vascular causes –

• Multi-infarct dementia.
  
• Occlusion of the carotid artery
  
• Stroke
  
• Hypertension
  
• Cranial arthritis

D. Metabolic and endocrine disorders :-

• Endocrinopathies – Addison’s disease, Cushing’s syndrome,  Hyperinsulinism,
• Hypothyroidsm, Hyporupituitatism, Hypoparathyrodism, Hyperparathyrodism.
  
• Hepatic failure
  
• Renal failure
  
• Renal dialysis
  
• Respiratory failure
  
• Hypoxia
  
• Chronic uraemia.
  
• Chronic electrolyte imbalance.
  
• Hypocalcaemia
  
• Hypercalcaemia
  
• Hypokalaemia
  
• Hyponatraemia
  
• Hyper natraemia
  
• Remote effect of Carcinoma or Lymphoma.

E. Nutritional Causes :-

1. Sustained lack of B12 pernicious anemia
          b)  Niacin – Pellagra
          c) Thiamine – Wernicke – Korsakoffs syndrome
2.  Vitamin intoxication – vitamin A , Vitamin D – Paget’s disease

F. Traumatic Causes :-    

1. Severe single head injury
2. Repeated head injuries  in boxers and others.

G. Infections and related conditions: -

• Encephalitis of any cause
  
• Neurosyphilic
• Chronic Meningitis
• Cerebral Sarcoidosis
  
• Cysticercosis
  
• AIDS and AIDS related complex.

H. Toxic Causes :

1. Alcohol
2. Poisoning with heavy metals – lead, arsenic, thallium, mercury, carbon monoxide.
3. Drug and alcohol withdrawal of anxiolytic sedative drugs, amphetamine.

I. Anoxia:-

1. Anemia
2. Post – anesthesia
3. Cardiac arrest
4. Chronic respiratory failure

SENILE DEMENTIA

It occurs usually after the age of 65 years due to degenerative brain changes as accompanied by a clinical picture of mental deterioration.

Types of Senile dementia

a) Simple deterioration :- In this patient gradually develops loses of  contact with environment poor memory, tendency to reminiscence, intolerance of change, disorientation, restlessness, insomnia, and failure of judgment. This is the commonest psychotic reaction in about 15% of the entire group of senile dementia.

b)  Paranoid reaction:-  Gradual formation of delusion. He feels that his relatives are turned against him and are trying to rob or kill him

c) The presbyophrenic type:- Characterized by jovial mood, marked impairment of memory, restlessness and excitability.

d) Depressed and agitated type:-  Severally depressed and agitated, suffers from hypochondrical and Nihilistic delusion .expresses morbid ideas about cancer, syphilis and other diseases. Has marked poverty of ideas.

e) Delirious and contused type: - Shows severe mental clouding, which make him restless, contused, resistive and incoherent. Completely disoriented to time, place and person.

All these type of senile dementia deteriorate and the patient becomes asocial and bedridden . He is reduced to a vegetative life.

PRE- SENILE DEMENTIA

It resembles that of senile dementia except that disorders occur in younger age group.
Alzheimer’s disease: - Dementia of insidious onset and slowly progressive course due to specific lesions in the brain–stem, hippocampus, parietal and frontal cortex The first sign are usually impairment of memory for recent events and inability to process information. Individual thinking becoming limited, inability to retain new information. The pattern of interference occurs according to the area of Brain is affected, Hippocampal damage cause memory, impairment, parietal lobe of brain damage cause difficulty in use of words or knowing the name of common objects also cause dyspraxia, frontal lobe damage cause impaired ability to behave appropriately, leading to tactlessness, dis-inhibition and loss of finer feelings, speech is also affected.

Usually developing age of Alzheimer's disease is between 40 to 50 yrs. Rapid progression with severe brain and mental deterioration, accompanied by over activity, emotional distress and agitation, frequent development of aphasia death occurs between 2 and 10 yrs of sickness, usually an average of 4 years. The patient should be hospitalized treatment is symptomatic.

Genetic factors: - Although the cause of dementia of the Alzheimer’s type remains unknown, progress has been made in understanding the molecular basis of the amyloid deposits that are a hallmark of the disorder’s neuropathology, some studies have indicated that as many as 40% of patients have a family history of dementia of the Alzheimer’s type thus, genetic factors are presumed to play a part in the development of the disorder, at least in some cases. Additional support for a genetic influence is the concordance rate for monozygotic twins, which is higher than the rate for dizygotic twins. (43% Vs 8%, respectively) In several well-documented cases, the disorder has been transmitted in families through an autosomal dominant gene, although such transmission is rare.

Neuropathology:- The classic gross neuroanatomical observation of a brain from a patient with Alzheimer’s disease is diffuse atrophy with flattened cortical sulci and enlarged cerebral ventricles.

Neurotransmitters: - The neurotransmitters that are most often implicated in the pathophysiological condition of Alzheimer’s disease are acetylcholine and norepinephrine, both of which are hypothesized to be hypoactive in Alzheimer’s disease. The decrease in nor epinephrine activity in Alzheimer’s disease is suggested by the decrease in norepinephirine containing neurons in the locus ceruleus found in some pathological examinations of brains from people with Alzheimer’s disease. Two other neurotransmitters implicated in the pathophysiological condition of Alzheimer’s disease are the Neuro active peptides somatostain and corticotropin, both of which have been found to be decreased in Alzheimer’s disease.

MULTI-INFRACT CAUSE

The primary cause of multi-infract dementia is presumed to be multiple cerebral vascular disease, resulting in a symptom pattern of dementia. It is most common in men, especially those with pre existing hypertension or other cardiovascular risk factors the disorder affects primarily small and medium size cerebral vessels , which under go infraction and produce multiple parenchyma lesions spread over wide areas of the brain . The cause of the infarctions may include occlusion of the vessels by arteriosderotic plaque or thromboemboli from distant origins. An examination of a patient may reveal carotid bruits, funduscopic abnormalities enlarged cardiac chambers.

PICK”S DISEASE

Pick’s disease is characterized by a preponderance of atrophy in the front temporal regions.  These regions also have neuronal loss, gliosis, and the presence of neuronal pick’s bodies, which are masses of cytoskeletal elements. Pick's bodies are seen in some postmortem specimens but are not necessary for the diagnosis. It is most common in men, especially those who have a first-degree relative with the condition. Pick’s disease is difficulty to distinguish from Alzheimer’s type, although the early stages of pick’s disease are more often characterized by personality and behavioral changes, with a relative preservation of other cognitive functions. Features of Kluver – Bucy syndrome (such as hypersexuality, placidity and hyperorality) are much more common in pick’s disease than in Alzheimer’s disease.

LEWY BODY DISEASE

Lewy body disease is a dementia clinically similar to Alzheimer’s disease and often characterized by hallucinations, Parkinsonian features and extrapyramidal signs, and lewy bodies are found in the cerebral cortex. The exact incidence is unknown. These patients show marked adverse effects when given antipsychotic medications.

HUNTINGTON’S DISEASE

Huntington’s disease is classically associated with the development of dementia. The dementia seen in this disease is the sub cortical type of dementia, characterized by more motor abnormalities and fewer language abnormalities than in the cortical type of Dementia. The dementia of Huntington’s disease exhibits psychomotor slowing and difficulty with complex tasks, but memory, language and insight remain relatively intact in the early and middle stages of the illness. As the disease progress, however, the dementia becomes complete; the features distinguishing it from dementia of the Alzheimer’s type are the high incidence of depression and psychosis, in addition to the classic choreoathetoid movement disorder.

PARKINSON’S DISEASE

It is characterized by bradykinesis, rigidity, and hyperkinesias, evident in slowness in initiating and executing motor acts. The unblinking face is mask like, writing is cramped and the gait is slow and shuffling with difficulty in starting and turning associated movements are lacking. Decreased motivation and spontaneity fatigability and feeling of depression are very common. There will be disturbance in other neurological condition which presenting symptom of the disorder.

NORMAL–PRESSURE HYDROCEPHALUS

Hydrocephalus is an increase in the intracranial cerebrospinal fluid volume associated with dilatation of the ventricular system. In the case of primary hydrocephalus an increased volume of CSF with in the cranial cavity can result from increased formation of CSF, an obstruction to its circulation or decreased absorption. This is turn leads to raised CSF pressure.

Normal – pressure hydrocephalus is both obstructive and communicating. It is caused by an obstruction in the subarachnoid space which prevents CSF from being reabsorbed, but allows it to flow in to the subarachnoid space from the ventricular system.

HYDROCEPHALUS IS ASSOCIATED WITH DILATATION OF THE VENTRICULAR SYSTEM

In Normal pressure hydrocephalus the features of raised ICP are generally absent. The syndrome mainly occurs in the 7th and 8th decades of life.  Varying degrees of cognitive impairment and physical slowness occur. Other features include unsteadiness of gait, urinary incontinence and nystagmus.  When it caused pre-senile dementia particularly If physical features are absent, it may prove difficult to differentiate normal – pressure hydrocephalus from Alzheimer’s disease.

TRAUMATIC CAUSES

HEAD INJURY

The commonest cause of head injury is motor vehicle accidents. Acute posttraumatic psychosis and the chronic Psychological sequence of head injury cause, cognitive impairment, personality change and neurotic symptoms. A common consequence of head injury which does not reflect the extent of brain damage is called post concussional or posttraumatic syndrome. Such as head ache dizziness, emotional liability, anxiety, irritability, sensitivity to noise, impaired concentration and subjective memory loss, confusion, disorientation and mood disturbance, also cause defect in memory and calculation, damage to the frontal lobe maybe followed by personality change towards a apathy and indifference.

SUBDURAL HAEMATOMA

Subdural haematoma commonly caused by head injury arise in association with clotting disorder. Acute haematoma associated with disturbed consciousness up to extreme of coma and neurological signs cause dementia.

EXTRACRANIAL CAUSE OF DEMENTIA

Systemic conditions may affect neuronal function through the blood stream, producing a dementia or a sub acute delirious syndrome.

ENDOCRINE DYSFUNCTIONS

Endocrine disorders, such as hyper and hypothyroidism, Addison’s disease, Cushing’s syndrome, acromegaly hyper and hypoparathyrodism and diabetes mellitus are all potential cause of an organic brain syndrome.

CEREBRAL ANOXIA

Cerebral anoxia arises from any hindrance to the transport of oxygen from the level of the alveoli to its place of eventual utilization with in neuron, respiratory failure cardiac failure, suffocation, severe anemia cerebral vascular disease and metabolic disturbances such hypoglycemia and cyanide, poisoning are all Important cause.

VITAMIN DEFICIENCY

Due to vitamin deficiency associated with chronic physical and mental illness, ageing and social disadvantage vitamin B group are associated with neuropsychiatry symptoms, chronic thiamine deficiency leads to beriberi with cardiac failure neuropathy and in acute cases Wernicke’s encephalopathy.

Nicotine acid deficiency leads to pellagra with triad to gastrointestinal disorder, dementia and psychiatric disturbance like, irritability, anorexia and emotional instability and delirium, vitamin biz deficiency cause sub acute combined degeneration of the spinal cord accompanied by a macrocytic anaemia and progressive dementia.

METABOLIC DISORDER

Hepatic and renal disease, electrolyte and fluid disturbances and acute porphyria. Hepatic failure is associated with marked neuropsychiatric symptoms. It cause liver disease is cause consciousness in impaired during episodes of ecephalopathy concentration and memory impaired.

Electrolyte imbalance cause lassitude, apathy and confusion associated with hyponatraemia, hypocalcaemia, hypercalcaemia, alkolosis and acidosis. Electrolyte abnormalities cause apathy, slowness and withdrawal, which may resemble dementia.

DRUG AND DEMENTIA :-

Reseprine, Methylopa and phenocetin cause chronic brain syndromes and chronic use of cannabis can produce mental and physical sluggishness, disturbance of recent memory and volition associated with chronic head ache and reversal of sleep rhythm. Drug use and use of cannabis associated cerebral atrophy.

III. EPIDEMIOLOGY

Dementia is essentially a disease of older people. About 5 percent of every one who reaches age 65 has dementia of the Alzheimer’s type, compared with 15% to 25% of everyone age 85 or older patients with dementia of Alzheimer’s type occupy more than 50 percent of nursing home beds. Over 2 million person with dementia are cared for in these homes. The risk factors for the development of dementia of the Alzheimer’s type include being female, having a first degree relative with the disorder, and having a history of head injury. Down’s syndrome is also characteristically associated with the development of dementia of the Alzheimer'’ type.

Alzheimer’s type generally occurs in late life, most commonly in the 60s, 70s and 80s and beyond , but in rare instances the disorder appears in the 40s and 50s (known as early-onset dementia). The incidence of Alzheimer's disease also increase with age and it is estimated at:-

0.5 %  Per year from age 65 to 69
1 % Per year from age 70 to 74
2 %  per year from age 75 to 79
3 % Per year from age 80 to 84
8 % Per year from age 85 onwards.

Progression is gradual but steadily downward, with an average duration from onset of symptoms to death of 8 to 10 years. Plateaus may occur, but progression generally resume after 1 to several years.

The second most common type of dementia is vascular dementia, which is causally related to cerebrovascular diseases. Hypertension predisposes a person to the disease. Vascular dementia accounts for 15 to 30% of all dementia cases. Vascular dementia is most common in people between the ages of 60 and 70 and is more common in men than in women. Approximately 10 to 15% percent of patients have coexisting vascular dementia of the Alzheimer’s type.

Other common causes of dementia, each representing 1 to 5 percent of all cases, include head trauma, alcohol related dementias, and various movement disorder related dementia’s such as Huntington’s disease and Parkinson’s disease. Because dementia is a fairly general syndrome. It has many causes and clinicians must embark on a careful clinical workup of a patient with dementia to establish its cause. The current annual cost of caring for patients with dementia is 15 billion, which is likely to increase. By the year 2030, an estimated 20% of the population will be older than age 65.