Chapter 13 Flashcards
The hallmark of schizophrenia is ___________
psychosis (loss of contact with reality)
First clinical description of schizophrenia
- 1810, John Haslam (apothecary in first psychiatric institution in Europe)
Benedict Morel ‘demence precoce’
- 1860
- described case of 13yo boy
- case had dementia features to it
- thought boys’ intellectual, moral, and physical functions deteriorated bc of brain degeneration of hereditary origin
Emil Kraepelin ‘dementia praecox’
- latin for demence precoce
- mental deterioration at an early age
- noted disorder characterized by hallucinations, apathy/indifference, withdrawn behavior, incapacity of regular work
- best known early definition
Eugen Bleuler (1857-1939)
- coined term schizophrenia
- schizo = to split; phren = mind
- disorder is lack of coherence between thought and emotion; to split from reality
Schizophrenia DSM-5 Criteria
- 2+ of symptoms present for at least 1mo
- delusions
- hallucinations
- disorganized speech
- grossly disorganized/catatonic behavior
- negative symptoms (ie dim. emotional expression)
Lifetime prevalence of schizophrenia
just under 1% (0.7%)
Risk factors for schizophrenia
- having father over 50 (at conception)
- parent in dry cleaning business
- first/second generation immigrants (esp Black Caribbean/African ppl living in white communities)
Onset of schizophrenia
- 18-30 (more likely early onset in men)
- more common/severe in men
- second and third peak in mid 40s and ealy 60s in women
- low estrogen worsens symptoms so might play a protective role in women
Delusions
- erroneous belief fixed/firmly held despite clear contradictory evidence (disturbance in content of thought)
- more than 90% of patients have them at some point
- ex thoughts being broadcast/inserted/taken away; neutral env. having special meaning; bodily changes/removal of organs
Hallucinations
- sensory experience that seems real but occurs in absence of any external perceptual stimulus
- auditory most common (75% of patients)
- likely that auditory hallucinations occur when patients misinterpret self-generated thoughts as coming from another source (show activation of Broca’s area-speech production-and not speech comprehension areas)
- visual in 39%
- patients become emotionally involved in hallucinations; incorporate them into delusions
Disorganized speech
- disorder in thought form (delusions are disorder of thought content)
- fail to make sense even though they are using language in conventional way
- may make up new words (neologisms)
Disorganized behavior
- elements of this often present in children even when no other symptoms are there yet
- impairment of goal-directed activity
- ex issues w hygiene, silliness, unusual dress
- catatonia: almost no movement
- catatonic stupor: virtual absence of all mvmt+speech
Positive symptoms of schizophrenia
- excess/distortion in normal behavior and experience
- “what there is more of”
- delusions, hallucinations
- most medications work primarily on positive symptoms!
Negative symptoms of schizophrenia
- absence/deficit of normally present behaviors
- reduced expressive behavior (ie blunted affect, alogia-little speech)
- reduced motivation/experience of pleasure (avolition/anhedonia)
- presence of negative symptoms not a good sign
Schizoaffective Disorder
- features of schizophrenia AND severe mood disorder
- “schizophrenia w a lot of emotional distress”
- poor diagnostic reliability
- moving toward needing to be in full depressive episode for diagnosis
- 10y outcome better than for schizophrenia patients
Schizophreniform Disorder
- schizophrenia-like symptoms lasting at least 1mo but less than 6mo
- basically less severe form of schizophrenia
- prognosis better than for schizophrenia
Delusional Disorder
- delusional beliefs w otherwise normal behavior
- erotomania delusion involves great love for someone (usually high status) – lots of stalkers!
- like nano-robots in covid vaccine thing
Brief Psychotic Disorder
- sudden onset of psychotic symptoms/disorganized speech/catatonic behavior
- typically lasts a few days
- usually triggered by high stress situation
Familial factors of schizophrenia
- tend to run in families (familial)
- prevalence in first-degree relatives is 10%
- second-degree relatives (share 25% of DNA) have 3% prevalence
- familial =/= genetic
- risk for identical twins is close to 50%
- this and bipolar are most genetically based disorders
Twin/adoption studies in schizophrenia
- concordance rate for MZ twins 28%, DZ twins 6%
- higher rates when biological parent has schizophrenia
- kids at high genetic risk raised in healthy environment ( and low-communication-deviance) don’t develop problems more than kids at low genetic risk
- so genetic risk + adverse environment is very bad!
Molecular genetics and schizophrenia
- probably involves many genes
- candidate genes: havent rly been identified
- genome-wide association study (GWAS) looks for profiles of aberrant genetic code (found 103 loci ass. w schizophrenia)
- COMT gene on chromosome 22 involved in dopamine metabolism (more likely to develop schizophrenia if gen. material del. or w cannabis use in adolescence)
- strongest finding is region on chromosome 6 (genes involved in immune functioning)
- some risk alleles also implicated in bipolar
Endophenotypes and schizophrenia
- trait that individuals who have this condition tend to have
- often present before individual develops condition
- discrete, stable, measurable trait thought to be under genetic control
Prenatal exposure in schizophrenia
- higher rates in children born to mothers in second trimester at time of influenza epidemic (viral infection during pregnancy can increase risk!)
- rhesus incompatibility between mother and infant can increase risk of brain abnormalities
Pregnancy/birth complications and schizophrenia
- delivery problems that affect oxygen supply are risk
- could be triggered by early nutritional deficiency
- SLE late in 1st trimester/early in 2nd
Attenuated psychosis syndrome
- new in DSM5 as disorder in need of futher study
- focus on prodromal (very early) signs
- ppl with this syndrome at risk for later psychosis
- commonly perplexed by reality (eg mix up dreams and reality)
Neurocognition in schizophrenia
- cognitive impairment is core feature
- almost all aspects of cognition are impaired
- lower IQ may be risk factor; higher IQ may be protective
- sharp decline occurs during transition from premorbid period to full-blown illness
- often see poor reaction times, poor Pro50 suppression (no habituation to sounds), eye tracking dysfunction (might be useful endophenotype for genetic studies)
Social cognition in schizophrenia
- significant impairments
- failure to recognize social hints
- difficulty recognizing emotions in faces/speech
Loss of brain volume in schizophrenia
- enlarged brain ventricles (more in males) is indicator of reduction in brain tissue
- decrease in volume present early in illness
- progressive deterioration for many years
- psychosis and cortical thinning go together
- gradual loss of gray matter in multiple regions (study found 3% decrease in 1y)
Affected brain regions in schizophrenia
Reduction of frontal and temporal lobes (memory, decision-making, processing auditory memory)
- prefrontal cortex
- medial temporal areas (decision-making)
- amygdala (emotion)
- hippocampus (memory)
- thalamus (sensory input)
- cause of abnormal brain structure unclear; might be related to stage of illness, medications
White matter problems in schizphrenia
- white matter important for connectivity of the brain
- abnormalities correlated w cognitive impairments
- reductions in volume AND structural abnormalities (abnormalities in first-episode patients and genetic high risk ppl)
- like if electrical wire system lost insulating coating
Brain functioning in schizophrenia
- hypofrontality (deficits to organize info and take action)
- impaired functioning of frontal lobes esp in early stages and those at high risk
- dysfunction of temporal lobes (how activity in diff. regions gets coordinated)
Cytoarchitecture in schizophrenia
- if cells don’t migrate properly, cytoarchitecture is compromised (increase in neural density in some areas)
- abnormal distribution of cells in cortex and hippocampus
- missing inhibitory interneurons (so can’t regulate overactivity)
Brain development in adolescence and schizophrenia
- major brain injuries in this period increase risk of developing schizophrenia
- ppl hospitalized for head injury have 65% increased risk
- if injured between 11-15 risk increased by 85%
Psychosocial and cultural aspects of schizophrenia
- past theory that family was to blame (conflicting messaging communication style) but no empirical evidence
- if not genetically at risk, adverse env has little effect
Expressed Emotion (EE) and schizophrenia
- measure of family environment based on how family member speaks ab patient in interview
- 3 elements: criticism, hostility, emotional overinvolvement (EOI)
- High-EE homes >2x chance of relapse (esp for chronically ill patients)
- still don’t know exactly how it affects the brain
Urban living as a risk factor for schizophrenia
- kids who spent first 15y in urban settign 2.75x more likely to develop schizophrenia
- estimated if we all lived in rural settings number of cases would decrease by 30%
Immigration and schizophrenia
- recent immigrants at much higher risk
- darker skin more at risk
- no evidence this can be explained by cultural misunderstandings
- ppl who feel discriminated against more likely to develop psychotic symptoms
Cannabis use and schizophrenia
- ppl w schizophrenia 2x more likely to smoke cannabis (might be correlate not cause)
- majority of cannabis users never develop schizophrenia
- might accelerate progressive brain changes
Diathesis-Stress model of schizophrenia
- genetic predispositions shaped by environmental factors (prenatal exposures, infections, stressors)
- genetic factors+prenatal/perinatal env.=brain vulnerability
- stress+developmental maturation processes act on brain vulnerability and lead to psychosis
Nongenetic risk factors for schizophrenia (7)
- older father
- virus exposure
- obstetric complications
- urban upbringing
- head injury
- cannabis use
- migrant status
Neurochemistry and schizophrenia
Dopamine linked to schizophrenia
- chlorpromazine blocks dopamine receptors (helps reduce psychosis)
- amphetamines produce excess dopamine and mimic psychotic state
- L-DOPA used in Parkinson’s might cause psychosis
Glutamate
- excitatory neurotransmitter
- when receptors blocked, schizophrenia-like symptoms (PCP and ketamine do this)
Pharmacological treatments of schizophrenia
- first gen antipsychotics (block action of dopamine); neuroleptics like chlorpromazine and haloperidol
- second gen antipsychotics (less parkinson-ish side effects)
- research on role of estrogen
Second-gen antipsychotics
- block dopamine receptors more selectively
- less likelihood of extrapyramidal (motor) side effects
- clozapine, olanzapine, risperidone, ziprasidone
Clinical outcomes of schizophrenia
- not favourable; lifelong condition
- 38% of patients thought of as recovered 15-25y after development of disorder (less delusions/hallucinations but don’t go back to normal)
- about 12% of patients need long-term institutionalization
- men die 14.6y earlier
- women w schizoaffective die 17.5y earlier
Neuropleptic Malignant Syndrome
- life-threatening idiosyncratic rxn to antipsychotic drugs
- fever, altered mental status, muscle rigidity, autonomic dysfunction
- associated w virtually all neuroleptics (incl newer atypical antipsychotics and other meds that affect central dopaminergic neurotransmission
Estrogen treatment and schizophrenia
- PANSS positive symptom scores go down with estrogen treatment over 28 days vs placebo
Patient perspectives in schizophrenia
- not all benefit from antipsychotics
- side-effects can lead to discontinued meds
- need other interventions (ie social skills)
- might avoid taking meds bc it confirms they are mentally ill
Treatment approaches in schizophrenia
- Case management (coordinating services)
- Family therapy
- Psychoeducation
- Social-skills training (transitional living unit)
- Cognitive remediation (training cognitive skills)
- CBT (address delusions)
- Exercise