Schizophrenia and addiction work together to have devastating effects on the lives of those affected. The diagnosis is staggering for both the patient and the family as the problems caused by one disease are compounded by the other.
Before examining the relationship between schizophrenia and addiction, it is important to understand what the main symptoms are in both cases.
What is schizophrenia?
The word schizophrenia comes from the combination of two Greek words: schizein (to split, divide) and phrēn (spirit, understanding, understanding). In short, it could be said that it is a division of the mind. The split subject seems to be in another world and has no strong attachment to reality (Padín, 2012).
Schizophrenia is a mental illness that affects the way a person thinks, feels, and acts. It is characterized by three types of symptoms: positive, negative, and disorganized.
- Delusional ideas
- Catatonic behavior
- Affective flattening
- Disorganized language
- Disorganized behavior
- Inappropriate affect
What are addictions?
Addictions can be understood as a pathological pattern of dependence on substances or activities. They are dangerous to physical and mental health. Sussman and Sussman (2011) assume that all addictions, whether on substances or behaviors, have the following symptoms:
- Dependence on aggravating consequences of addiction
- Brooding, worrying, and craving for the addictive behavior or substance
- Temporary saturation or tolerance
- Loss of control
- Difficulty stopping or avoiding using or addictive behavior when there are negative consequences.
How are schizophrenia and addiction related?
The relationship between schizophrenia and addiction is demonstrated by several aspects:
Prevalences between schizophrenia and addiction
It is estimated that 47% of people with schizophrenia will have substance abuse at some point in their life (Mueser, Bennett, and Kushner, 1995). In addition, 50-60% of male patients are addicted to drugs or alcohol in some form (Dixon et al., 1990).
Along with tobacco, alcohol is one of the most commonly abused substances among schizophrenic drug users. Aznar et al. (2020) found in a study conducted in Madrid that 29.5% of patients diagnosed with schizophrenia consumed alcohol. That figure was only exceeded by tobacco use, which was 69.8%.
The prevalence of smoking in mental health is high: it is around 90% of schizophrenics and 45-70% of patients with other mental illnesses, compared to 25-30% in the general population (Aznar et al., 2020). These unhealthy and pathological habits increase the risk of other diseases that can affect not only the well-being of the patient but that of their family as well.
Explanations for the connection between schizophrenia and addiction
It is not yet known exactly how schizophrenia and addictions are related, but some models can explain this pattern:
The diathesis stress model
This explanatory model assumes that schizophrenia is the result of a neurobiological vulnerability caused by environmental stressors. That is, the affected person has a biological predisposition to this pathology, but the environment is responsible as the trigger for the disease.
People with schizophrenia are at increased risk for substance use disorder due to the cumulative effects of poor cognitive, social, academic, and professional functions in the presence of poverty, victimization, and a deviant social environment (Mueser, cited in Khokhar, 2018).
The self-medication hypothesis
This hypothesis suggests that schizophrenic patients use drugs to relieve the symptoms of their illness or to mitigate the side effects of antipsychotic treatment.
People often try to find a solution to their condition’s problems and turn to treatments that are ineffective and can make the disease worse over time.
This hypothesis suggests that both schizophrenia and substance abuse share a common pathophysiology in the neural circuitry. Substance abuse may be related to a disruption of the reward circuitry in the brain in patients with schizophrenia (Khokhar, 2018).
It is known that dopamine neurotransmitter systems play a role in both the development of schizophrenia and addictive behavior (Batel, 2000).
The biopsychosocial relationship between schizophrenia and addiction
We can observe a biopsychosocial relationship between schizophrenia and addiction. The product of the interaction includes biological factors such as the reward and dopaminergic systems in the brain, environmental factors that expose the patient to stressful situations, and psychological factors related to the person’s cognitive function.
The consequences of the interaction between the two pathologies cannot therefore be viewed as the individual sum of the effects. In other words: There is no clinical picture that specifically applies to this combination. Therefore, the intervention also requires different strategies, which are also used when both diseases are considered separately.