Schizophrenia and Addiction

Today, our understanding of schizophrenia has progressed significantly from the 20th century when individuals with the condition were often stigmatised as simply ‘crazy.’ Many people with schizophrenia now lead fulfilling lives through effective management.

Contemporary medicine recognises that the causes of schizophrenia are intricate, involving a combination of genetic predisposition and environmental factors. Moreover, there is an acknowledged association between schizophrenia and addiction.

What is schizophrenia?

Schizophrenia is a chronic and severe mental disorder that affects a person’s thinking, emotions and behaviour. People with schizophrenia often experience a range of symptoms that can significantly impact their daily functioning and quality of life. The exact cause of schizophrenia is not well understood, but it is believed to involve a combination of genetic, biological and environmental factors.

The onset of schizophrenia typically occurs in late adolescence or early adulthood and it can have a significant impact on various aspects of a person’s life. Treatment usually involves a combination of antipsychotic medications, psychotherapy and support services.

While there is no cure for schizophrenia, with appropriate treatment and support, many individuals with the condition can manage their symptoms and lead fulfilling lives. Individuals with schizophrenia need to work closely with mental health professionals to develop an effective treatment plan tailored to their specific needs.

Schizophrenia symptoms

Note: It’s important to state that the symptoms can vary in severity and may come and go. A qualified mental health professional should provide diagnosis and treatment.

Here are some common symptoms of schizophrenia:

  • Delusions: Individuals with schizophrenia may believe that others are plotting against them, that they have special powers, or that external forces are controlling them.
  • Hallucinations: Perceptions that occur without any external stimuli. Auditory hallucinations (hearing voices) are the most common, but visual hallucinations can also occur.
  • Disorganised thinking: Difficulty organising thoughts and connecting them logically. This can manifest as incoherent speech, making it challenging for others to understand the person.
  • Abnormal motor behaviour: This may include unpredictable or inappropriate movements, agitation, or catatonia (lack of movement or response).
  • Negative symptoms: These involve a decrease or loss of normal functioning. Examples include reduced emotional expression, social withdrawal, lack of motivation, and difficulty initiating and sustaining activities.
  • Cognitive symptoms: Impairments in memory, attention and executive function may be present, making it difficult for individuals with schizophrenia to plan and organise their lives.
  • Impaired insight: Many individuals with schizophrenia may not be aware of their symptoms or the impact of their behaviour on others. This lack of insight can complicate treatment and management.
  • What are the different types of schizophrenia?

    The Diagnostic and Statistical Manual of Mental Disorders (DSM-5), which mental health professionals commonly use, categorises schizophrenia into different subtypes. However, it’s important to note that the DSM-5 has moved away from the subtypes approach and now emphasises a dimensional approach to diagnosing schizophrenia based on symptom severity.

    Nevertheless, below, we list the earlier types of schizophrenia, as they are still commonly understood by the general public.

    • Paranoid schizophrenia: This subtype is characterised by prominent delusions and hallucinations. Individuals with paranoid schizophrenia often experience auditory hallucinations or delusions of persecution or conspiracy.
    • Disorganised schizophrenia: This subtype is characterised by disorganised speech and behaviour. Individuals may have difficulty organising their thoughts and may exhibit inappropriate emotional responses. Daily activities can be severely impaired.
    • Catatonic schizophrenia: This subtype involves disturbances in movement, ranging from excessive and purposeless activity to a near-total lack of movement (catatonia). Catatonic schizophrenia is relatively rare.
    • Undifferentiated schizophrenia: This category is used when a person does not fit into one of the above subtypes, displaying a mix of symptoms from different types of schizophrenia.
    • Residual schizophrenia: This subtype is used when an individual has experienced at least one episode of schizophrenia but currently displays milder symptoms or residual impairment.

    What causes schizophrenia?

    The exact cause of schizophrenia is not fully understood and it is likely to involve a complex interplay of genetic, biological and environmental factors. Here are some factors that may contribute to the development of schizophrenia:

    Genetic factors
    There is evidence that genetics plays a role in the risk of developing schizophrenia. Individuals with a family history of schizophrenia have a higher likelihood of developing the disorder. However, the presence of a genetic predisposition does not guarantee that someone will develop schizophrenia.
    Brain structure and neurochemistry
    Differences in brain structure and neurotransmitter imbalances, particularly involving dopamine, serotonin and glutamate, have been implicated in schizophrenia. Abnormalities in the structure and function of certain brain regions, such as the prefrontal and medial temporal lobe regions, are also observed in individuals with schizophrenia.
    Neurodevelopmental factors
    Disruptions in early brain development, potentially influenced by genetic and environmental factors, may contribute to the onset of schizophrenia. This could include factors such as prenatal exposure to toxins, maternal illness during pregnancy, or early childhood trauma.
    Psychosocial factors
    Stressful life events, traumatic experiences and a dysfunctional family environment may contribute to the development or exacerbation of schizophrenia in susceptible individuals. High levels of stress can potentially trigger the onset of symptoms in those predisposed to the disorder.

    It’s important to note that these factors are not mutually exclusive and the combination of genetic vulnerability and environmental stressors is likely to play a significant role in the development of schizophrenia.

    Why do addiction and schizophrenia often co-occur?

    Unfortunately, those who have schizophrenia have been shown to have more of a predisposition to addiction, especially substance use disorder.

    Individuals with schizophrenia commonly experience co-occurring substance use disorders, with notably high prevalence rates. Alcohol use disorders are prevalent, with rates ranging from 21% to 86%, while cannabis and cocaine use disorders show prevalence rates of 17–83% and 15–50%, respectively. These figures are strikingly higher than those observed in the general population.

    The elevated rates of substance use disorders in individuals with schizophrenia pose significant challenges. Co-occurring substance use disorders in this population have been linked to various adverse outcomes, including clinical exacerbations, non-compliance with treatment, poor global functioning, increased risk of violence, elevated suicide rates and higher rates of relapse and re-hospitalisation. These complications underscore the critical need for targeted interventions and support systems to address both the psychiatric and substance use aspects of individuals with schizophrenia.

    So, why does this happen? According to research, sadly, there is no concrete answer. But, there are many theories put forward as to why schizophrenia and addiction co-occur so often.

    Fowles (1992) & Museser et al. (1990)

    The diathesis-stress model, also known as the “two-hit” model, suggests that a biological vulnerability interacts with environmental stressors, such as substance use, leading to schizophrenia (Fowles, 1992). Another related idea, the cumulative risk factor hypothesis, proposes that individuals with schizophrenia are more likely to develop substance use disorder due to the combined impact of poor cognitive, social, educational and vocational functioning, along with factors like poverty, victimisation and deviant social environments (Mueser et al., 1990).

    Green et al. (1999) & Chambers et al. (2001)

    An alternative biological theory, sometimes called the “primary addiction hypothesis” (Chambers et al., 2001) or “reward deficiency syndrome” (Green et al., 1999), proposes that schizophrenia and substance use disorders have a shared underlying biology in overlapping neural circuits. According to this theory, substance use in individuals with schizophrenia might be linked to dysfunction in the brain’s reward circuit.

    Khantzian (1997)

    The self-medication hypothesis is a prominent explanation for the elevated comorbidity rate observed in individuals with schizophrenia and substance abuse. This theory suggests that people with schizophrenia may turn to drug use as a way to cope with various aspects of their illness or to alleviate undesirable side effects associated with antipsychotic medications, such as dysphoric reactions or extrapyramidal symptoms.

    In recent years, though, the self-medication hypothesis has declined in appeal and influence, partly overshadowed by the growing emphasis on fundamental neurobiological research.

    Can substance use bring on schizophrenia?

    All of the hypotheses we explore in the previous section focus on schizophrenia leading to addiction, but what about the other way around? Below we take a look at the hypotheses that focus on substance use that could potentially bring on schizophrenia in later life:

    Fergusson et al. (2003) & Arseneault et al. (2002)

    Several studies have explored the potential link between cannabis use, particularly during adolescence and the risk of developing schizophrenia later in life. According to Ferguson et al. (2003), individuals with cannabis use disorder at ages 18 and 21 exhibited notably higher rates of psychosis compared to non-cannabis users. Additionally, Arseneault et al. (2002) discovered that adolescents who used cannabis at age 15 had an increased likelihood of developing a schizophreniform disorder by age 26, even after accounting for prior psychotic symptoms, in comparison to their non-using counterparts.

    Chadwick et al. (2013)

    Patients with schizophrenia commonly use substances such as tobacco, alcohol and cannabis and initiating use during adolescence is linked to a heightened risk of future substance use. Although the neurodevelopmental effects of drug exposure in adolescence remain not entirely clear, insights from prior epidemiological and pre-clinical studies offer valuable clues about the lasting changes in addiction vulnerability resulting from such exposure.

    Overall, it appears that there is stronger research supporting the connection between schizophrenia and addiction rather than the reverse. However, it is important to note that much of the research, including the aforementioned studies, tends to concentrate on adolescent drug use that may contribute to the development of schizophrenia in the future rather than emphasising prior addictions.

    How are schizophrenia and addiction treated in rehab?

    The presence of both addiction and schizophrenia as a dual diagnosis can complicate the treatment process, given the intrinsic connection between these two conditions. At UKAT, our team specialises in addressing addiction in the presence of schizophrenia, guiding numerous individuals through significant strides in their recovery journey.

    To initiate rehab treatment at UKAT, your schizophrenia symptoms must be stable. This precaution is essential because the treatment can be mentally challenging, potentially worsening schizophrenia symptoms. Once your condition attains stability, you can commence your rehabilitation at UKAT, where we ensure you receive prescribed medications and additional support tailored to your needs.

    Following this, you will start a comprehensive programme of addiction counselling therapies, designed not only to facilitate recovery but also to offer substantial benefits for schizophrenia symptoms.

    These therapeutic approaches include:

    Dialectical Behaviour Therapy (DBT)
    DBT therapy focuses on emotion regulation and improving relationships. It’s beneficial for those with schizophrenia, addressing emotional control and reducing substance dependence by teaching effective emotion management without reliance on addictive substances.
    Family Therapy
    This therapy involves the family in the treatment, aiding those with schizophrenia and addiction. It fosters open communication, helping families grasp the challenges of both conditions.
    Mindfulness-Based Therapy
    This therapy uses mindfulness techniques like meditation to manage stress and emotions. It benefits addiction and schizophrenia by improving emotional regulation and reducing related anxiety or stress.
    Group Therapy
    Group therapy, beneficial for those with schizophrenia and addiction, provides peer support and reduces isolation, boosting self-esteem through shared experiences.

    What’s next?

    If you or someone close to you is facing the challenges of schizophrenia coupled with addiction, it is crucial to take the initial step of reaching out to professional assistance. UKAT offers a secure and caring setting for addiction recovery, concurrently addressing and managing schizophrenia symptoms effectively. Contact us today to explore our treatment choices and embark on the path to recovery.

    Call us now for help

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