Schizophrenia Flashcards
Schizophrenia
A serious debilitating mental disorder (“psychosis”) that manifests itself during early adulthood. Its frequency (≈1 %), core symptoms and course are quite uniform across all cultures.
Kraepelin History
Emil Kraepelin – 1887
o He differentiated between ‘dementia praecox (premature/early onset)’ and ‘manic depression’ as the two forms of psychosis.
o Kraepelin considered ‘dementia praecox’ (which is nowadays known as schizophrenia) as a biological illness caused by anatomical or toxic processes which automatically resulted in irreversible loss of cognitive functions. In contrast, he described manic depression as an episodic disorder, which does not lead to permanently impaired brain function.
o Both the International Classification of Diseases (WHO) as well as APA’s DSM-Classification still rely on Kraepelin’s concept.
Bleuler History
Eugen Bleuler - 1908
o Introduced the term schizophrenia
o Believed that schizophrenia was an organic illness and that it could be inherited and that dementia was a secondary symptom
o Separation among personality, cognition, memory, and perception
o Disorder of dissociation
o ‘Negative symptoms’ are the core feature of the disorder
Schneider History
Kurt Schneider – 1920s o Criteria for schizophrenia – groundwork for DSM and ICD10 diagnosis o First ranked symptoms: o Auditory Hallucinations o Passivity experiences (external force controlling the body) o Thought withdrawal o Thought insertion o Thought broadcasting o Delusional perception o Psychosis as core feature
Diagnosis DSM 5
At least two symptoms (and at least 1 from 1-3) for at least one month (attenuated symptoms for at least 6 months)
Positive Symptoms (i.e. something new that ideally should not be there)
1) Delusions
2) Hallucinations
Cognitive Symptoms (i.e. Ineffective encoding, retrieval, and processing)
3) Disorganized speech e.g. frequent derailment or incoherence
4) Disorganized behavior e.g. catatonia
5) Negative symptoms
flat affect (no or inappropriate emotions)
alogia (poverty of speech)
avolition (little interest or drive)
Paranoid-hallucinatory schizophrenia
o Patient (22) with family history of mental illness o Since 2 years: Decrease in general performance, strange behaviour, social withdrawal, concentration problems, o Talks in a strange way, invents words, laughs at inappropriate moments o Imagines the neighbours talking about him, TV news is also about him, suspicious of parked cars, thinks house is bugged and the NSA is after him
Natural History and Course of Schizophrenia
Premorbid Phase - Prodromal Phase - Psychotic Phase - Stable Phase
Premorbid: Cognitive, motor or social defects
Prodromal: Brief/attenuated positive symptoms and/or functional decline
Psychotic: Florid positive symptoms
Stable: Negative symptoms, cognitive/social deficits, functional decline
Schizophrenia - a heterogenous spectrum
o Variety to disorders in the psychotic spectrum like brief psychotic disorder, schizophreniform disorder (when symptoms of schizophrenia are present for significant amount of time like a month but not long enough i.e. 6 months for it be diagnosed as schizophrenia), delusional disorder or schizoaffective disorder (where symptoms of both psychotic and mood disorders are present together during one episode or in close proximity of each other).
o There is a symptomatic (and genetic) overlap to the affective psychoses, i.e. bipolar disorder (mania and depression) and major depressive disorder
o There is also a symptomatic (and genetic overlap) to neurocognitive or affective disorders. i.e., autism spectrum disorder (ASD)
o A direct brain alteration may mimic any mental disorder including schizophrenia eg: drugs (amphetamines/cocaine, Phencyclidine (PCP), ketamine) or Head trauma or emotional trauma.
Catatonic Schizophrenia
Catatonia is a complex neuropsychiatric behavioral syndrome that is characterized by abnormal movements, immobility, abnormal behaviors, and withdrawal.
When individuals flip between decreased and excessive motor activity
Catatonia has historically been related to schizophrenia (catatonic schizophrenia), but it is now known that its symptoms are nonspecific and are observed in other mental, neurological, and medical conditions especially mood disorders. It is not a stand alone diagnosis and is used to describe a feature of the underlying disorder.
Dimensional Approach to Schizophrenia in DSM - 5
o Categorical diagnosis of schizophrenia and other psychotic disorders does not work and is not accurate.
o Within a categorical system, the DSM-5 aims to capture the underlying dimensional structure of psychosis
o There are five domains of psychopathology that define psychotic disorders. The level of psychosis, the number of symptoms, and the duration of psychosis are the gradients that have been used to demarcate psychotic disorders from each other and continue to be used for the same purpose in DSM-5.
o The dimensions refer to a structure of psychosis that is not simply categorical but allows for much greater flexibility in the assessment of psychopathology, including aspects that are not considered as defining domains of psychosis.
-You can check the slides for the detailed image-
Epidemiology and Risk Factors
o Lifetime-Prevalence: around 1% (world-wide)
o Sex differences: Age of onset of psychosis in women is ~5 years later (bimodal distribution in women) and The lifetime prevalence is equal in men and women, but men tend to be more severe with greater negative symptoms and longer duration illness
o Perinatal and early childhood risk factors: Obstetric complications, low birthweight, in-utero-infection, Increasing age of the father, Maternal infections during pregnancy (e.g., influenza)
o Environmental factors: Infections (T. gondii), High expressed emotion families, Growing up in large cities (Odds ratio (OR) ≈2), Immigration status (OR=2-5)
Toxoplasma gondii
T. Gondii is a single cell parasite that can only reproduce in the intestine of a cat.
It usually infects human with no seen effects.
In animals, infection with Toxoplasma gondii can alter behavior and neurotransmitter function (eg, infected mice forget their fear for cats).
In humans, acute infection with T. gondii can produce psychotic symptoms similar to those displayed by persons with schizophrenia (psychomotor dysfunction, depression, bipolar disorder, addiction, and suicide). Infection increases the risk of schizophrenia by 2-8 fold.
Risk Factors
o Genetics is the major risk factor. It is a complex genetic disorder with high heritability (80 %)
o Neurotransmitters systems
o Dopamine-agonists induce positive symptoms
o Glutamate-antagonists may induce all core symptoms
o Dysfunction of GABAergic (inhibitory) neurotransmission
o All antipsychotics block D2-receptors
o Associated with changes in the structure and functioning of a number of key brain systems, including prefrontal and medial temporal lobe regions involved in working memory and declarative memory, respectively. As well as in the connections between different cortical regions. Structural deficits, such as reduced gray matter volume and disrupted white matter integrity, have also been observed and these changes may be progressive during the pre-onset phase of the disorder, as well as in the early post-onset period.
o The two-hit hypothesis for schizophrenia suggests that a prenatal genetic or environmental “first hit” disrupts some aspect of brain development, and establishes increased vulnerability to a second hit that may occur later in life
Treatment
Positive symptoms:
o Antipsychotic medication
o Electroconvulsive therapy (ECT)
o Repetitive transcranial magnetic stimulation (rTMS) (?)
Negative symptoms:
o Clozapine (?)
o Psychosocial interaction
o Cognitive behavioral therapy
o Neurocognitive symptoms:
o Cognitive remediation therapy
o rTMS (?)
o Vocational training
Antipsychotics
o Used for treatment of schizophrenia, schizoaffective disorder, affective disorders, dementia, delusional disorder, substance-induced psychosis and others o Heterogeneous class of medications o First discovered in the 1950s (chlorpromazine)
First generation (“typical”): efficacy against positive symptoms (delusions, hallucinations) o butyrophenones (haloperidol), phenothiazines (chlorpromazine), thioxanthenes (zuclopenthixol) o Side effects: extrapyramidal symptoms (EPS) including parkinsonism, dystonia, akathisia and tardive dyskinesia
Second generation (“atypical”): o clozapine, olanzapine, risperidone, ziprasidone, quetiapine, aripiprazole (sometimes “third generation”) o Side effects: Agranulocytosis/neutropenia (clozapine), weight gain, diabetes, hyperlipidemia, lower risk for EPS
Side effects of all antipsychotics: sedation, hyperprolactinemia, neuroleptic malignant syndrome, fatty liver, sexual dysfunction, QT elongation and others
