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.

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.

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.

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: