Schizophrenia and Related Psychoses

Females)

Higher rate in urban than rural areas

Higher rate in immigrant

Aetiology

Very complex, controversial, however the whole range of  biological, psychological and social factors are important.

Genes: e.g. Neuregulin, Dysbindin Environmental: Obstetric complications, maternal influenza, winter birth, early cannabis use, paternal age. Social: Migration, urban birth and upbringing, recent life events Structural :smaller brain size, reduced synaptic markers Functional imaging: Hypofrontality Neurophysiological: Abnormal eye tracking, Abnormal esenory evoked potential Neurochemical: Dopamine, Glutamate Psychological: cognitive impairment, personality factors, psychodynamic theories, family dynamic and communications

Main hypothesis are the Neurodevelopmental (The pathological changes are laid down early in life, presumably through genetic influences and then modified by maturational and environmental factors), aberrant connectivity, Stress-vulnerability.

Key aspect of the present consensus regarding the aetiology are summarised as follows:

The most important influence is genetic, with about 80% of the risk being hereditary. The mode of inheritance is complex and the genes, some of which have been recently identified, act as a risk factor, not determinant of illness. A number of environmental factors contribute too, many of which appear to act prenatally, and which interact with the genetic predisposition. Together these and subsequent risk factors lead to neurodevelopmental disturbance which either causes, or renders the individual vulnerable to,, the later emergence of symptoms, and which manifests itself premorbidly in a range of behavioural, intellectual and neuroanatomical features. In schizophrenia, the brain is slightly smaller than normal, and there are localized differences in its structure and function, leading to the view that the syndrome is a disorder of connectivity within and between brain regions. Acute psychosis is associated with excess dopamine, whereas the persistent cognitive impairment may result from deficient dopamine function in the prefrontal cortex, both maybe secondary to abnormality to the glutamate system.

Course and prognosis

Generally agreed that the outcome of schizophrenia is worse than that of most psychiatric disorders, however, prognosis may not be as bad as previously thought!

 After 13 years follow up:

15-20% of first episodes will not recur 50% are without psychotic symptoms 50% are without negative symptoms 55% show good social function.

Mortality and morbidity is much higher than normal population and suicide up to 10%.

Good prognostic Factors:

Sudden onset Short episode No previous psychiatric history Prominent affective symptoms Paranoid type Older age of onset Married Good psychosexual adjustment Good premorbid personality Good work record Good social relationships Good compliance. Normal brain morphology (e.g. normal ventricles)

 Factors’ acting after the illness has been established

Cultural background: incidence is similar in different countries but the course and outcome is different, studies suggest that patient in developing countries have favourable course compared to developed ones (after emission). Life events (stress) Social stimulation: under stimulation associated with worsening of the negative symptoms and over stimulation with worsening of the positive symptoms. Social background and belief Expressed Emotion (hostility, criticism, emotional over involvement) extremely important cause for relapse. Patient living in families with high level of E.E have 2 to 3 times increased risk of relapse.

Management and treatment:

History

MSE

Physical Examination

Investigation (physical and psychological)

Treatment:

v Pharmacological

Antipsychotic Medications:

1. Conventional antipsychotics:

Chlorpromazine, Thioridazine, Haloperidol (all act to reduce dopamine levels)

Side effects:

  EPSE (extrapyramidal side effects)

-Acute Dystonia: contraction of muscles to maximal limit, typically sternocleidomastoid and tongue, although can be widespread (e.g. opisthoclonus); eye muscles involvement (oculogyric crises) may occur. Very distressing. Treatment with procyclidine i.v

-Parkinsonism: tremor, rigidity and bradykinesia occurring >1 week after admission. Consider dose reduction or procyclidine oral.

-Akathisia: restlessness, usually of lower limbs, and drive to move. Occurs usually > 1 month after treatment. BDZ and propranolol used for treatment. Often goes undiagnosed. Associated with risk of violence and

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