Lecture 23: Schizophrenia Flashcards
What is the etymology of the word schizophrenia?
Greek
schizophrenia = skhizein + phren
skhizein: split
phren: mind
dissociation of different cognitive functions
What was Emil Kraepelin’s contribution to the classification of schizophrenia?
“dementia praecox” (1887)
onset in adolescence
chronic deteriorating course
permanent and pervasive functional deficits
core symptoms are loss of cognitive functions (memory, planning, complex decision making, etc.)
What What was Eugen Bleuler’s contribution to the classification of schizophrenia?
“schizophrenia” (1911)
hallucinations and delusions are secondary features (positive symptoms)
primary symptoms are: ambivalence (can’t make decisions), loosening of associations (don’t move between topic logically), incongruous affect (facial and behavioral expression of emotions), autism (responding to internal stimuli, only internal)
What is the DSM-5 criteria for the diagnosis of schizophrenia?
two or more of the following for a significant proportion of time over a one-month period: delusions, hallucinations, disorganized speech, disorganized or catatonic behavior, negative symptoms
significant social or occupational dysfunction
signs of the disturbance are present over 6-months
not due to schizoaffective disorder or exclusively occurring during the course of a mood disorder
not due to a substance or a general medical condition
if a pervasive developmental disorder is present, prominent delusions or hallucinations are present for a month
What are hallucinations?
a perception in a conscious state in the absence of a stimulus, nothing the environment, no external stimulus
no indicative of schizophrenia
What is an illusion?
a misperception of a stimulus
think you heard someone call your name
What are the different types of hallucinations?
can be in any sensory domain: auditory, visual, olfactory, gustatory, tactile (formication, intoxication, or withdrawal), nociceptive (pain), chronoceptive (perception of time)
auditory hallucinations are the most common in schizophrenia
visual hallucinations are more common with substance use
What are some other causes of hallucinations separate from schizophrenia?
substances
dementia
delirium
migraine (aura, flashing lights)
epilepsy
intracranial infection or tumor
associated with sleep (hypnagogic or hypnopompic)
What are delusions?
a fixed, false belief not in keeping with an individual’s culture
defined as bizarre when not possible or patently untrue
non-bizarre: possible, but not true
What are the negative symptoms of schizophrenia?
deficit symptoms of schizophrenia
apathy: lack of motivation
anhedonia: lack of pleasure
amotivation: won’t even eat without being told
alogia: don’t make sense
poor social function: causes lots of impairment
contribute more to functional impairment than hallucinations or delusions
less amenable to treatment
What are cognitive symptoms of schizophrenia?
slowed processing speed
impaired attention
impaired memory
impaired executive function (decision making, social cognition, extraction)
impaired social cognition
impaired verbal comprehension
What is the chronic course of schizophrenia?
schizophrenia is a chronic illness
patients are usually diagnosed when they begin to exhibit disorganized behavior or hallucinations or delusions
What is the age of onset of schizophrenia?
male: 15-25 years
female: 25-35 years
age of onset before 15 years and after 50 years is rare
What is the initial prodromal phase of schizophrenia?
attenuated symptoms (not hallucinations or delusions, but perhaps off ideas or sensory misperceptions)
hard to know until positive symptoms occur
anxiety, sleep disturbances, mood problems
functional decline
precedes pychosis by 1 year on average
What is the first episode of psychosis in schizophrenia?
treatment results in remission of positive symptoms
negative symptoms will persist
What are the residual symptoms of schizophrenia?
half of patients require social supports
still causes impairment
negative and cognitive symptoms persist
What happens to the symptoms of schizophrenia over time?
over the course of the lifetime, positive symptoms become less prominent (learn that when they talk about symptoms they get hospitalized, so stop talking about them)
negative symptoms and cognitive symptoms persist
the best predictor of future functional impairment is the level of function after the first episode, if you don’t achieve functional levels then it’ll get worse
What is the course of schizophrenia in males?
males with schizophrenia are less likely to marry, and have a worse prognosis than females with schizophrenia
social factor: it occurs later in life in females
biological: estrogen might be a protective factor
What is the epidemiology of schizophrenia?
sex ratio: M:F = 1:1, recent research shows a slightly higher risk for males
annual incidence 1 in 10,000
lifetime prevalence 0.7-1%
What is the relationship between the Dutch famine of 1944 and the prevalence of schizophrenia?
children conceived during the famine had an increased rate of schizophrenia (2%)
likely this was due to poor nutrition during pregnancy and while breastfeeding, insults in the brain during development
What are the risk factors of schizophrenia?
family history: monozygotic twins have a 40-50% concordance
urban birth: psychotic individuals migrate to cities and give birth there
first-generation immigrant: related to the stress of culturization, true of refugees too
winter birth: seasonal birth
prenatal infection or malnutrition
obstetrical complications
increasing paternal age
What is the ultra high risk phenotype for schizophrenia?
most commonly defined as family history of psychosis and at least 1 of: attenuated positive symptoms, brief psychotic symptoms, functional decline
about 50% of these individuals will present with symptoms of schizophrenia within a year of identification
show executive dysfunction, working memory problems
What are “refrigerator mothers”?
idea from the 1940’s
mothers fail to give appropriate emotional feedback to children
children become autistic or psychotic
no evidence to suggest this is the case
increased paternal age leads to increased risk
What is the genetics involved in schizophrenia?
22q11 deletion: Velocardiofacial syndrome
linkage analysis shows up to 4000 genes associated with schizophrenia, mostly involved with development, or dopamine, or glutamate pathways
candidate genes include those for: Catechol-O-methyl transferase (COMT), neuroregulin 1, dysbindin, dopamine receptors, glutamate receptors
