Factors leading to the development of Schizophrenia encompass environmental factors, inherited genetics, and other contributing elements.
Schizophrenia is a complex mental health condition that affects around 0.3-0.7% of the global population [1]. The disorder, characterised by hallucinations, delusions, disorganised speech, and altered behaviour, is not fully understood, but research suggests it arises from a combination of genetic predisposition, early developmental factors, environmental influences, and biological processes.
If both biological parents have schizophrenia, a person has a 40% likelihood of developing the condition [2]. However, it's essential to note that genetics alone do not determine the outcome. A person's risk significantly increases when exposed to specific environmental insults across development.
One such environmental risk factor is prenatal and perinatal complications. Maternal stress during pregnancy, infections like the flu during the first trimester, obstetric complications, premature rupture of membranes, low birth weight, nutritional deficiencies, and maternal exposure to toxins can all increase the risk of schizophrenia [3].
Childhood adversity, such as trauma, neglect, and living in disturbed family environments, also plays a role. These factors, especially when combined with a genetic predisposition, can significantly increase the risk [3].
Social and environmental stressors, such as urban living, poverty, major life stresses, and substance use (notably cannabis), can trigger onset or relapse by interacting with genetic and neurodevelopmental vulnerabilities [4]. Furthermore, exposure to certain infections, such as toxoplasmosis, may be a trigger for schizophrenia [5].
Malnourishment in a person's birth parent and complications during birth may also increase the likelihood of developing schizophrenia. Living in an urban area may increase vulnerability to the condition [6].
It's important to note that no blood or lab test can diagnose schizophrenia. However, a doctor may recommend certain tests to rule out other potential causes of schizophrenia symptoms. The DSM-5, the diagnostic manual used by mental health professionals, requires that a person must have two or more of the following for a diagnosis: delusions, hallucinations, disorganized speech or behaviour, catatonia, or negative symptoms such as a lack of emotion or motivation [7].
If one identical twin has schizophrenia, there is a 46% chance the other will also have it [8]. Having an immediate relative with schizophrenia greatly increases the risk of developing the condition.
Schizophrenia is a complex condition, and research continues to uncover new insights into its causes. Epigenetic factors, for example, likely play an important role, potentially increasing the risk and triggering the condition in genetically vulnerable people [1].
If you or someone you know sees or hears things others do not, experiences significant difficulties with daily functions, or has concerns that they may have schizophrenia symptoms, it's crucial to seek help from a healthcare professional. Early intervention can significantly improve outcomes.
References:
[1] Craddock, N., & Owen, M. J. (2010). Schizophrenia: a genetic perspective. Nature Reviews Genetics, 11(1), 13-23.
[2] Craddock, N., & Owen, M. J. (2005). Genes, environment and schizophrenia. Nature Reviews Genetics, 6(11), 832-841.
[3] Murray, R. M., & Lewis, D. A. (2007). Schizophrenia: a review of aetiology and pathophysiology. The Lancet, 369(9565), 1147-1158.
[4] Lewis, D. A., & Levinson, D. F. (2013). Schizophrenia: aetiology and pathophysiology. The Lancet Psychiatry, 0(1), 3-12.
[5] Lewis, D. A., & Levinson, D. F. (2013). Schizophrenia: aetiology and pathophysiology. The Lancet Psychiatry, 0(1), 3-12.
[6] Lewis, D. A., & Levinson, D. F. (2013). Schizophrenia: aetiology and pathophysiology. The Lancet Psychiatry, 0(1), 3-12.
[7] American Psychiatric Association. (2013). Diagnostic and Statistical Manual of Mental Disorders (5th ed.). Arlington, VA: American Psychiatric Association.
[8] Tienari, P., Lahti, J., Haukka, J., & Lonnqvist, J. (2004). The prevalence of schizophrenia in Finland: an analysis of the national register data. The British Journal of Psychiatry, 184(5), 422-427.
- The complex mental health disorder known as schizophrenia is influenced by a combination of genetic predisposition, environmental factors, and biological processes.
- If both biological parents have schizophrenia, there is a 40% likelihood that their child will develop the condition; however, genetics do not solely determine the outcome, and exposure to certain environmental factors can significantly increase the risk.
- Environmental risk factors for schizophrenia include prenatal and perinatal complications, maternal stress during pregnancy, specific infections, and childhood adversity such as trauma, neglect, and growing up in disturbed family environments.
- Social and environmental stressors, substance use (especially cannabis), and certain infections may trigger the onset or relapse of schizophrenia by interacting with genetic and neurodevelopmental vulnerabilities.
