Schizophrenia Medical Assignment Help

The term schizophrenia was coined by the Swiss psychiatrist Eugen Bleuler in 1908 as a ‘rending (disconnection) or splitting of the psychic functions’. The normal integration of emotional and cognitive functions is ruptured in schizophrenia. The annual prevalence of the condition ranges between 2 and 4 per 1000. The lifetime risk of contracting schizophrenia is 1%, but for firstdegree relatives of sufferers it is 12%. High rates have been reported in the north-west of the former Yugoslavia
and among the Tamils of south India.

CAUSES

No one cause has been identified to date. A number of possible causes have been implicated and are the subject of research. Biological causes are indicated in Table 19.9. Psychological theories suggest that schizophrenics have an impaired ability to handle the amount and speed of incoming perceptual stimuli and/or that some schizophrenics have a left hemisphere limbic dysfunction. A popular social theory suggests that disturbances in family relationships or communication are the cause, but the evidence is poor. Studies of so-called expre ssed emotion suggest that schizophrenic patients are particularly vulnerable to highly expressed emotions, and such family atmospheres increase the chances of relapse in treated patients as do intensive psychotherapy and social demands.

CLINICAL FEATURES

The illness can begin at any age but is rare before puberty; the peak age of onset is in late adolescence and the early twenties. The overall sex incidence is about equal. Schizophrenia is probably not a specific condition but rather a number of clinical syndromes. The symptoms that have been considered as diagnostic of the condition have been termed first-rank symptoms and were described by the German psychiatrist Kurt Schneider. They consist of:

• Auditory hallucinations-patients hear their own thoughts spoken aloud and/or hear one or several voices referring to themselves in the third person or referring to them by name, and/or hear voices commenting on their behaviour
• Thought withdrawal, insertion and interruption
• Thought broadcasting
• Delusional perceptions
• External control of emotions
• Somatic passivity and feelings-patients believe that thoughts or acts are due to the influence of others.

The World Health Organization’s International Pilot Study of Schizophrenia has shown that the presence of any  one of these symptoms, in the absence of physical disease, is highly discriminating for the diagnosis in a variety of countries and cultures. Other symptoms of acute schizophrenia include behavioural disturbances, thought disorder, hallucinations, delusions and mood abnormalities.

Chronic schizophrenia is characterized by thought disorder and the so-called negative symptoms of underactivity, lack of drive, social withdrawal and emotional emptiness. Motor disturbances can occur but they are extremely rare. Such disorders are often described as catatonic and include stupor, excitement, mannerisms, stereotypies and automatic obedience. Delusions in chronic schizophrenia are often held with little emotional response (the so-called systematized delusions) and may be encapsulated from the rest of the patient’s beliefs and behaviour.

Genetic
40% risk for children of two affected parents
50% risk for monozygotic twin of affected individual
Possible locus on chromosome 5
Dopamine
Dopamine agonists (e.g. amphetamine) exacerbate the condition
The therapeutic potency of neuroleptics is directly related to their ability to block dopamine receptors
in the brain
Withdrawal of dopamine antagonists causes rebound of symptoms in some patients
Post-mortem studies show increased dopamine binding sites in the brains of affected patients
Brain damage (e.g. in utero from long-acting virus)
Enlargement of lateral ventricles and widening of cerebral fissures and sulci on CT scans of a subgroup
of patients
Other
Disturbance in transmethylation
Abnormalities in monoamine oxidase function

Possible biological causes of schizophrenia.

DIFFERENTIAL DIAGNOSIS

Schizophrenia must be distinguished from:

Organic psychiatric disorders
• Affective disorders
• Personality disorders

The most important organic disorders, particularly in young patients, are drug-induced psychoses and temporal- lobe epilepsy. Some of the drugs that can produce psychosis are listed in Table 19.10.

In older patients, any acute brain syndrome as well as dementia can present in a schizophrenia-like manner. A helpful diagnostic point is that clouding of consciousness and disturbances of memory do not occur in schizophrenia and visual hallucinations are unusual.

Affective disorders present with a more sustained disturbance of mood and any delusions and hallucinations that are detected are usually understandable in terms of the mood disturbance. First-rank symptoms are not normally a feature of affective disorders. Differentiating insidiously arising schizophrenia from a personality disorder in a young person can be exceptionally difficult and the passage of time may be needed for the condition to be clarified.

COURSE AND PROGNOSIS

The prognosis of schizophrenia is highly variable. The patient’s psychosocial environment appears important in that in an understimulating environment negative symptoms worsen, whereas in an excessively stimulating environment positive symptoms may emerge or worsen. Some patients only suffer acute episodes that leave them relatively unimpaired; others insidiously develop chiefly negative symptoms. The most common presentation and course is an initial acute episode of floridly positive symptoms followed by the emergence and persistence of negative symptoms.

Glucocorticoids
Anticholinergic agents
Sympathomimetic central stimulants
Phenytoin
Carbamazepine
Disulfiram
Metronidazole
Cardiac glycosides
Hallucinogens, e.g. LSD, mescaline, ecstasy
Amantadine
LSD, lysergic acid diethylamide

Drugs causing psychosis

Prognostic factors in schizophrenia.

Prognostic factors in schizophrenia.

TREATMENT

The best results are obtained by combining drug and social treatments

Antipsychotic (neuroleptic) drugs

These act by blocking DI and D2 dopamine receptors, so reducing psychomotor excitement and controlling many of the symptoms of schizophrenia without causing disinhibition, confusion or sleep. Such drugs are most effective against acutely occurring, positive symptoms and least effective in the management of chronic, negative symptoms. Complete control of positive symptoms can take up to 3 months and premature discontinuation of treatment can result in prompt relapse.

The phenothiazines are the most extensively used group of neuroleptics. Chlorpromazine (l00-1O00 mg daily) is the drug of choice when a more sedating drug is required. Trifluoperazine is used when sedation is undesirable. Fluphenazine decanoate is used as a longterm prophylactic to prevent relapse (25-100 mg i.m.every 1-4 weeks). Promazine or thioridazine are useful in the elderly when it is desirable to reduce the risk of extrapyramidal and anticholinergic side-effects. As antipsychotic drugs block both Dl and D2 dopamine receptors, they usually produce extrapyramidal side effects. This limits their use in the maintenance therapy of many patients. They also block adrenergic and cholinergic receptors and thereby cause a number of unwanted effects (Table 19.12).

In patients manifesting good prognostic features and responding well to drugs, treatment may be discontinued under supervision after several months. Poor prognosis schizophrenia, on the other hand, usually requires regular maintenance therapy for many months or even years.

Clozapine, a new and atypical neuroleptic drug, is being used in patients with intractable schizophrenia
(approximately 20% of patients) who have failed to respond to at least two conventional antipsychotic drugs. This new drug is a dibenzodiazepine with a higher affinity for Dl than D2 receptors. Hitherto, a drug’s antipsychotic potency has been related to the blockade of the D2 receptors.

It is claimed that clozapine has dramatic therapeutic effects on negative symptoms, cognitive function and quality of life, but control trials are still in progress. However, this drug is expensive and produces severe agranulocytosis in 1-2% of patients. Therefore it can only be prescribed to registered patients by doctors and pharmacists registered with the Clozaril patient-monitoring service.

The starting dose is 25 mg per day with a maintenance dose of 150-300 mg daily. White cell counts should be monitored weekly for 18 weeks and then 2-weekly for the length of treatment.

Common effects
Extrapyramidal
Acute dystonia
Parkinsonism
Akathisia
Tardive dyskinesia
Autonomic
Hypotension
Failure of ejaculation
Anticholinergic
Dry mouth
Urinary retention
Constipation
Blurred vision
Metabolic
Weight gain
Rare effects
Hypersensitivity
Cholestatic jaundice
leucopenia
Skin reactions
Others
Precipitation of glaucoma
Galactorrhoea
Amenorrhoea
Cardiac arrhythmias
Seizures
Retinal degeneration (with thioridazine in high doses)

Unwanted effects of neuroleptic drugs .

Psychological treatment

This consists of reassurance, support and a good doctorpatient relationship. Psychotherapy of an intensive or exploratory kind is contraindicated.

Social treatment

Social treatment involves attention being paid to the patient’s environment and social functioning. Patients with any degree of residual impairment and negative symptoms usually require rehabilitation in a structured work and social environment. Parents and relatives need advice concerning the optimum amount of emotional and social stimulation to be provided for the patient. Some patients can manage a normal job, whereas others require a sheltered workshop. A very small number of severely disabled patients require long-term residential medical and nursing care.

The treatment of most psychiatric conditions is multidisciplinary, that is to say, in addition to the active involvement of psychiatrists and psychiatric nurses, other professionals including psychologists, psychiatric social workers, community psychiatric nurses, occupational therapists and counsellors play important therapeutic roles. This is particularly true in the case of the major psychoses. While psychiatrists and psychiatric nurses are crucially involved in the hospital management of such conditions, community psychiatric nurses play important roles in maintaining patients within the community. Psychologists, in addition to their skills in assessing the psychological status of patients, deliver cognitive, behavioural and other forms of therapy while occupational therapists work within hospital and community settings to assess and improve patient’s social and occupational skills.

Continuum of normal and abnormal mood.

Continuum of normal and abnormal mood.

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