Schizophrenia - F20 Flashcards
What are some epidemiological features of schizophrenia?
1% will have diagnosis in lifetime
Prevalence – 200/100,000
Incidence – 20/100,000
18-25 incidence most common in men
25-30 incidence most common in women
Higher in inner city, low socioeconomic environments
25yrs premature mortality - suicide, CVD, resp, infection
What are some genetic risks for schizophrenia?
Population risk – 1% If sibling has condition – 10% If parent has condition – 10-15% If both parents have condition – 45% Monozygotic twin - 50%
What are some medical and environmental risk factors?
Obstetric complications - higher incidence
Environmental - negligible? some adoption studies show same risks as non-adopted children; some studies suggest urban environment is a slight risk
What are some individual risk factors?
Childhood - if withdrawn, eccentric, clumsy
Sensitive personalities - tendency to perceive criticism harshly, even taking not critical comments as such
What are some risks for the triggering of schizophrenia?
Increased stress
Intense emotion – positive or negative
Increased levels of criticism from friends and family members
Drugs
i) Hallucinogens
ii) Stimulants
iii) Alcohol
iv) Cannabis*
v) Steroids
What is some suspected pathophysiology of schizophrenia?
Excess dopaminergic activity - evidenced by antipsychotic drugs and the converse effects of dopamine agonists
Glutamate - glutamate agonists can also cause psychotic effects; Often increased glutamate receptors in the frontal cortex of patients with schizophrenia but decreased in the medial and temporal lobes
Anatomy - Imaging sometimes shows:
Increased lateral ventricle size; Reduced brain size, esp temporal lobes; Negative symptoms correlate with reduced blood flow and other frontal cortex abnormalities; Reduced connections between different brain areas on EEG
What is the prodrome to schizophrenia?
Loss of interest; Social withdrawal; Self-neglect Depression; Anxiety; Brief psychotic episodes
Long prodrome can mean delayed diagnosis and poor prognosis
What is the difference between positive and negative symptoms in schizophrenia?
Positive - feelings or behaviours that are not usually present
Negative - lack of feelings or behaviours that are usually present
What are some examples of positive symptoms?
Hallucination - auditory, visual etc
Delusions - primary, persistent, secondary
Thought disorder - insertion, broadcast, withdrawal
Passivity experiences
What are some types of auditory hallucination?
Third person – talking about the individual who hears them; single/multiple; often critical; may not disappear with treatment (but may get quieter/nicer); most common auditory hallucination in schizophrenia
Thought echo – individual hears thoughts spoken aloud, simultaneous with speech of thought or just following
Second person – talking to the individual; also present in other mental disorders
Auditory hallucinations in which the person talks to the voice they hear are most commonly the result of trauma or are fictitious
What other hallucinations can occur?
Visual, olfactory etc
Also common in other, organic brain disorders - underlying cause must be medically investigated
Define a delusion
Unshakable belief that is not in keeping with person’s social, cultural or educational background for which there is no evidence
What are primary delusions?
Primary delusions – appear with no precipitating event and not in correlation with some other psychopathology; individual may appear in a ‘perplexed’ state for several days or months → as perplexity disappears, delusion develops
What are persistent delusions?
Persistent delusions – arise with the period of perplexity; can be diagnostic for schizophrenia if other symptoms are present; if not present – can indicate delusional disorder
What are secondary delusions?
Secondary delusions – arise when other symptoms of schizophrenia have been present for a period of time before the delusion and arise from strange experiences the individual has because of their schizophrenia
What is thought insertion?
Patient believes somebody is ‘planting’ thoughts in their mind against that persons will
What is thought broadcast?
Patient believes thoughts are ‘broadcast’ to others against their will
What is thought withdrawal?
Patient believes thoughts are being removed from their mind against their will, leaving their minds ‘blank’
What is a neologism?
Made up a word or give an existing word a new meaning that is only apparent to the individual and does not make sense
What is ‘word salad’?
The form of sentences makes no sense at all, words are mixed up