3- Environmental Risk Factors Flashcards
7 environmental risk factors associated with schizophrenia
Season of birth
Viral epidemics
Population density
Prenatal malnutrition
Substance abuse
Interactions
Obstetric complications
Research support associating season of birth to schizophrenia development
People born in late winter and early spring are more likely to develop schizophrenia
Research support associating viral epidemics to schizophrenia development
Increased schizophrenia in people born after an influenza epidemic
Research support associating population density with schizophrenia development
Schizophrenia likelihood 3 times higher in people living in middle of large cities than those living rurally
Research support associating prenatal malnutrition to schizophrenia development
Low-birth-weight babies more likely to develop schizophrenia
Research support associating substance abuse and schizophrenia development
Tobacco use in pregnancy –> increased schizophrenia risk
Research support associating interactions with schizophrenia development
Mothers having pyelonephritis in pregnancy mean that a child is twice as likely to develop schizophrenia and 4 times more likely if there is a family history
Research support associating obstetric complications with schizophrenia development
Higher schizophrenia risk when there is an emergency C-section, uterine complications, or foetal oxygen deprivation
How does cannabis relate to schizophrenia?
Cannabis use associated with increased risk
3 hypotheses about the association between tobacco and schizophrenia
- Shared genetic influences
- Smoking as a risk factor
- ‘Self-medicating hypothesis’
3 limitations of observed associations with environmental factors
- Don’t control for underlying genetic factors
- Difficult to control for confounds
- Associations don’t prove causation
What is the social defeat hypothesis?
Increased schizophrenia risk is caused by long-term exposure to social defeat causing sensitisation of mesolimbic dopamine pathway
What model is integrated into the social defeat hypothesis?
Sociodevelopmental-cognitive model
