Psychology Chapter on Schizophrenia and Cannabis

Psychosis vs. Schizophrenia

• Schizophrenia is a type of psychosis that persists, meaning symptoms last for at least a year.

Cannabis & Severe Mental Illness

• Link between cannabis and severe mental illness: THC and CBD have both positive and negative effects on mental health. Managing cannabis use is a crucial facet of treatment.
• Impact of cannabis on overall health: Cannabis use can exacerbate heart conditions, contribute to depression, and hinder work/education. It can also increase violence, affect relationships, and negatively impact treatment and recovery.
• Reasons for cannabis use: Individuals may use cannabis to self-medicate for symptoms like boredom, depression, anxiety, or to calm down. The causative role is also being researched – cannabis can induce psychosis and is misused as it can worsen symptoms in individuals already suffering from psychosis. Impulsive personality and cognitive factors also encourage the use of cannabis, along with experienced childhood adversity and possible genetic predisposition.
• Causative role of cannabis/THC: Cannabis, particularly THC, doubles or triples the risk of developing psychosis or relapse. Skunk, a particular strain of cannabis, is high in THC and linked to a higher likelihood of severe mental illness. THC can induce psychosis-like symptoms and exacerbate existing symptoms.
• Cannabis for treating mental illness: CBD has shown a small benefit as an anti-psychotic for some positive symptoms, but research is still evolving.
• Service user perspective: Many individuals don't realize cannabis is harmful or causes psychosis, and the clinician needs a delicate approach to get them to discuss substance use.
• Reasons for quitting cannabis: Common reasons include health concerns and expectations of use.
• Barriers to quitting cannabis: Cravings, withdrawal symptoms (low mood etc.), and social norms are common difficulties.
• NICE psychosocial treatments: Treatment options such as brief motivational interviewing and self-help interventions (CBT, mindfulness) are recommended.

Schizophrenia

• Characteristics of Schizophrenia: A severe and persistent psychotic illness characterized by symptoms such as hallucinations (seeing/hearing things).
• Dopamine and Genes: Schizophrenia often shows a complex interplay between dopamine and genes (D&G), and there is a genetic component.

Schizophrenia Dopamine Hypothesis

• Excess dopamine and psychosis: Excess striatal dopamine (presynaptic) is a potential pathway to psychosis.
• Antipsychotic treatment: Antipsychotics, dopamine blockers, are used to treat psychosis, potentially by mitigating the excessive release of dopamine.
• Dopamine's role: Dopamine usually mediates the salience of ideas and objects. However, the excess dopamine causes abnormal salience, and delusions arise from attempts to explain these abnormal perceptions.

Genetics

• PGC study: Research indicated a considerable genetic contribution to schizophrenia (263 to 100,000 genes associated with increased likelihood). Individuals inherit these genes, but some might inherit more of the ones associated with schizophrenia than others.
• Shared genes: Schizophrenia often shares genetic predisposition with other disorders like bipolar disorder (75%), depression, OCD, and anxiety.
• Similar onset: Symptoms of the mentioned disorders frequently begin in adolescence and tend to respond to similar treatments.

Prenatal/Perinatal Risk

• Pregnancy & delivery risk: Prenatal and perinatal complications, such as abnormal growth, asphyxia, and hypoxia during delivery, can impact neurodevelopment and increase the risk of psychosis.
• Neurological damage: These complications can damage neuroconnections.

Copy Number Variants (CNVs)

• Neurodevelopmental issues: CNVs (Copy Number Variants – specific changes in the number of copies of any given DNA sequence segment) can disrupt neurodevelopment.
• Autism prevalence: CNVs are implicated in 20% of autism cases.
• Specific CNV implications: Deletions of specific genes can be linked to autism, learning disabilities, and epilepsy. Duplication of these genetic segments can raise the risk for schizophrenia.

Social Factors Increasing Psychosis Risk

• Childhood Adversity: Childhood abuse/neglect.

• Migration/Ethnic Minority: Migration/living as an ethnic minority.

• Bullying/Stress: Bullying and other forms of intrusive events or experiences like violence, urban surroundings, and living in the inner city.

• Adverse Life Events: Stressful life experiences.

• Impact on Dopamine: All these factors seem to impact striatal dopamine.

Continuum of Liability to Psychosis

• Gradual risk: Psychosis was previously viewed as a discrete illness. However, now it's understood that there is a range of liability, where schizophrenia can overlap with bipolar disorder.
• Susceptibility genes: Hundreds of susceptibility genes contribute to the development of Schizophrenia.
• Multiple causes: There are multiple causes, including environmental and genetic factors, that are implicated in the development of schizophrenia.

Test your knowledge on schizophrenia, cannabis use, and their implications for mental health. This quiz covers defining characteristics, risk factors, and treatment options related to psychosis and cannabis use. Dive deep into the complexities of mental health and neurobiology.