The correlation between cannabis use and psychosis has been extensively researched over many years, revealing a nuanced relationship that defies simplistic explanations. Psychosis, simply put, involves a detachment from reality, characterised by delusions, hallucinations, and a loss of contact with one's surroundings. These episodes can vary in duration, ranging from days to years, often signalling the onset of other mental health conditions.
Recent media attention, particularly in Ireland and elsewhere, has drawn focus to this connection, with some attributing crimes to psychosis induced by cannabis, even leading to its use as a defence in a murder trial. However, upon closer examination, the link between cannabis and psychosis reveals complexities that defy easy conclusions.
Consider the analogy of ice cream sales and drownings increasing during the summer months—while both may occur concurrently, it doesn't mean one causes the other. Similarly, associating cannabis use with psychosis requires a more nuanced understanding beyond mere correlation. It's a reminder that correlation does not imply causation, urging us to delve deeper into the evidence.
Chicken or the Egg
In the ongoing debate about the relationship between cannabis and psychosis, a fundamental question arises: which comes first, the chicken or the egg? This analogy aptly captures the complex interplay between cannabis use and the development of psychotic disorders. Consider this scenario: individuals at risk for psychosis may experience symptoms such as anxiety or mood disturbances before the onset of a full-blown psychotic episode. In an attempt to alleviate these distressing symptoms, some may turn to cannabis as a form of self-medication. However, while cannabis use may provide temporary relief for some, it is not necessarily the cause of psychosis itself. Rather, it may serve as a coping mechanism for pre-existing psychological distress.
Conversely, emerging evidence suggests a paradoxical relationship where symptoms of psychosis could precede cannabis use. In this scenario, individuals experiencing early signs of psychosis may instinctively seek relief from their distress by using cannabis. In such cases, the cannabis use may be a consequence of the underlying psychotic symptoms, rather than the instigator. This phenomenon underscores the intricate nature of the cannabis-psychosis relationship, challenging simplistic notions of causality.
Pull the trigger
In the intricate web of mental health and substance use, cannabis occupies a unique position, often implicated in triggering or exacerbating psychosis without necessarily being the sole instigator. It's akin to a domino effect where cannabis, among various other substances, can act as the tipping point, setting off a cascade of psychological disturbances. Picture it as a delicate balance on a scale, where the introduction of cannabis can tip the equilibrium, leading to the emergence of psychosis in susceptible individuals.
Consider this scenario: just as certain external factors can disturb the tranquillity of a calm lake, triggering ripples that disrupt its surface, cannabis can disturb the delicate balance of neurochemical processes in the brain, potentially precipitating psychotic symptoms. This disruption, however, does not imply a direct causative relationship; rather, it underscores the complex interplay between cannabis use and individual susceptibility to psychosis. Moreover, while various substances, such as psychostimulants, steroids, psychedelics, and alcohol, have been linked to substance-induced psychosis, cannabis emerges as the primary suspect in many cases. It's like identifying a recurring character in a series of unfortunate events; while other substances may play supporting roles, cannabis often takes centre stage in triggering this uncommon form of psychosis.
Additionally, in individuals experiencing substance-induced psychosis, those who consume cannabis are more prone to transitioning to schizophrenia over time. This suggests that cannabis may not only induce temporary psychosis but also contribute to the development of schizophrenia.
Spanner in the works
Adding further complexity to the relationship between cannabis and psychosis, research indicates a third possible explanation. Evidence suggests that specific genes may predispose individuals to both cannabis use and psychosis, indicating a shared genetic foundation. In essence, certain genetic factors could influence an individual's susceptibility to both cannabis consumption and the development of psychosis. This shared genetic basis introduces another layer of intricacy to understanding the interplay between cannabis use and the onset of psychotic symptoms.
Causation vs Correlation
While cannabis use alone is unlikely to directly cause schizophrenia, it's essential to consider the bigger picture. Despite a significant increase in global cannabis consumption over the past 70 years, rates of schizophrenia have remained stable. In the specific context of Ireland, 2022 had the lowest report of admissions for schizophrenia, as a primary diagnosis in four years, while the lifetime prevalence of cannabis consumption increased. We must also acknowledge the significant challenge facing people attempting to access mental health services in Ireland. Shockingly, nobody under the age of 18 has access to early intervention psychosis services, highlighting the limited support available for young individuals experiencing early signs of psychosis. Furthermore, citizens of Ireland experience the highest level of difficulty in accessing mental health services compared to citizens of the 27 EU member states, indicating a critical deficit in accessible care for those seeking mental health support. Adding to these challenges, only 1% of mental health services in Ireland are currently regulated, underscoring the need for comprehensive oversight and quality assurance within the mental health care system.
Nevertheless, it is crucial to recognise that for vulnerable individuals, cannabis use may precipitate the onset of psychosis or schizophrenia at an earlier age, presenting a significant public health concern. This premature manifestation of psychotic disorders can impede both biological and psychological development, potentially exacerbating the severity of symptoms. In light of these considerations, individuals with a personal or family history of schizophrenia are advised to exercise caution regarding cannabis use and may consider abstaining from its use unless medically necessary and under professional supervision. This cautious approach extends to individuals with relatives affected by severe mental illness, highlighting the importance of informed decision-making regarding cannabis consumption. Notably, while potent forms of cannabis containing high levels of THC have been associated with exacerbating psychotic symptoms, it is important to recognize that CBD, another cannabinoid present in cannabis, has shown mild antipsychotic properties. This distinction underscores the need for careful consideration of cannabis composition and individual susceptibility when evaluating its potential impact on mental health.
As society increasingly accepts cannabis, understanding its benefits both medically and therapeutically, we must understand the risks associated with cannabis. Correlation does not equal causation, but awareness of personal risk factors and cautious consumption practices are vital.