Link between Schizophrenia and Cannabis
Mayra A Palencia
The City College of New York
Abstract
In today’s society the consumption of cannabis has been growing as well as its usage due the demand of medical marijuana. Even though medical marijuana is helping people deal with pain in a more natural approach, it seems that the use of marijuana is a concern in young adults according to research. Due to the continuous brain development from birth to around 25 years of age, scientist have linked the usage of cannabis interfering with brain function and development. If a person has a predisposition of schizophrenia, cannabis would increase the risk even more. Being that the correlation to marijuana usage and schizophrenia is fairly new, there are experts who disagree with this stance, and believe that marijuana does not increase the chance of a person getting schizophrenia. Some researchers believe that consumption of marijuana doesn’t increase the onset of mental disorders, but that people who are already suffering from psychosis are more prone to use drugs. There is a battle between researchers on which side is right, but ultimately we need more search done.
Link between Schizophrenia and Cannabis
Mental illnesses are some of the most stigmatized disorders that people have to deal with. Some choose not to speak about their diseases because of fear of how they may be perceived, and some people quite do not understand what is happening to them when they are suffering from said diseases. Schizophrenia is one of the many diseases where people already have a preconceived idea of what the disease looks like: it is that lonely person on the train station, or street talking to themselves, and fighting with an imaginary person, they are pacing back and forth and lost in this imaginary world that can only be seen through their eyes. This is not always the case, John Nash, a world renown mathematician who made pivotal contributions to game theory and won The Nobel Peace Prize for his contributions to math was diagnosed with paranoia schizophrenia and suffered by the hands of this mental disorder (The Nobel Prize, 2015). Researchers still do not know the direct pathway to what is causing this illness, but they have concurred the possibility that there is a correlation between the usage of cannabis and schizophrenia, but other researchers believe there is no link between schizophrenia and the use of cannabis. Nonetheless, more research must be done to help create reforms for the protection of people if in fact there is a link between cannabis and schizophrenia, especially at a time where there is a push for more recreational use in young adults, and the usage of cannabis for medical reasons.
According to The National Alliance on Mental Illness, schizophrenia is a mental disease that affects women and men equally with range from 0.25% to 0.64% prevalence in the United States. The average onset of this illness beings in the late teens and early 20s in men, and in women the onset time is greater, and usually occurs in late 20s to early 30s. It is unlikely for a person to be diagnosed with schizophrenia under the age of 12, and over 40 years of age. In regard to this disease, people usually associate schizophrenia as a debilitating disease that usually leads to homeliness and crime, but this is not necessarily every case scenario for people with this mental illness. People are able to live well with schizophrenia if kept on a proper medical routine. The National Institute of Mental Health states that schizophrenia can be categorized in two categories: Negative symptoms, where a person lacks characteristics that should be present, either by disruptions in emotions and behavior. People with negative symptoms may present with reduced emotions, speech, facial expression, feelings of pleasure, speaking, and not enjoying activities what were once pleasing. Positive symptoms are addition of psychotic behavioral characteristics. This type of schizophrenia is the one more people are familiar with. A person suffering from schizophrenia may “lose touch” with aspects of reality and suffer from hallucinations, delusions, unusual thoughts, and agitated body movements. Hallucinations are considered as sensory experiences without any sensory stimuli. People suffering from hallucinations can hear voices, see things, or even smell and taste things that others cannot perceive. These sensory experiences are very real to them and can lead to isolation, and deviant behavior. Delusions on the other hand, are false beliefs that are constant and don’t change when presented with facts or new ideas, and can transcend to bizarre behavior (NAMI, 2019). Even though scientists are ambivalent with what causes schizophrenia, they have several possible causes like genetics, environmental, brain chemistry, and usage of substances. Researchers believe that a person is more than six times more likely to develop schizophrenia if they have a close relative with this illness (Jun Chou, 2016). Brain chemistry is also seen as a plausible cause, because neurotransmitters can be affected by certain brain chemicals, and its networks. Furthermore, there seems to be a link between substance use and schizophrenia. There have been studies that link the usage of drugs like cannabis in adolescences and young adulthood to schizophrenia. “A growing body of evidence indicates that smoking marijuana increases the risk of psychotic incidents and the risk of ongoing psychotic experiences. The younger and more frequent the use, the greater the risk” (NAMI, 2019). This finding can be alarming because cannabis is being used for recreational use in young adults when the brain hasn’t fully developed.
Research has looked at what is possibly causing the onset of schizophrenia and some have concluded that marijuana might be increasing the chances of this illness, even though there aren’t clear cut links, many studies have indicated a possibility that this is causing schizophrenia. In the article “Psychotic Patients Who Used Cannabis Frequently Before Illness Onset Have Higher Genetic Predisposition to Schizophrenia Than Those Who Did Not,” Monica Aas et al. demonstrated the there is a possible link between two psychosis illness, in which schizophrenia was one, and the onset of early use of cannabis before the first symptoms of the disorder. The study that they conducted involved looking at participants before and after the ages of 18 and how frequently they used cannabis. Their findings showed that that frequent use of cannabis (daily or weekly) before symptoms, in fact was associated with a higher risk of schizophrenia, but she also implied that the genetic predisposition of suffering from psychosis can lead to a higher risk of using cannabis (Monica Aas, 2017) Despite the fact that their study does show a correlation between these two factors, that does not necessarily means it’s causation She states further research is still needed to strengthen their findings. Aas study wasn’t the only one that saw a possible linkage between this disorder and cannabis usage. The prevalence of drug usage in adolescence seem to be a significant risk factor in developing this disease, especially if there is a frequent usage of drugs. (Khokhar et el., 2017) reported that in a study done with young adults from the ages of 18 to 21 showed a higher rate schizophrenia when they used cannabis, than young adults who non-cannabis consuming participants (Fergusson et al., 2003). Evidence suggest that the relationship between these two factors lies in the makeup of the brain and what goes on during the phases of neural synapses creations and pruning of these later non-functional synapses.
Synaptic pruning occurs from the time of birth to 20 years of age, eliminating the redundancy of synapses that the brain doesn’t use, but when important synapses are eliminated, it can diminish the possibilities of developing alternative neural pathways that can help circumvent the damaged ones. This process has been connected with mental illnesses that emerge in adolescences like schizophrenia, because there is an alteration of the brain and its function (Scientific American, 2017). Evidence suggest that there is a region in the brain that is rich in cannabinoid receptor type 1 (CB1), which facilitate the process of synaptic pruning. CB1 receptors are found in the prefrontal cortex that is associated with planning of complex behaviors, but this region is also associated with psychotic illnesses. The captivating part is that the use of cannabis engages the use of these receptors, which then facilitates the process of synaptic pruning and increases the risk of schizophrenia, but scientists also found that people can be predisposed, or have disorders that have an expression of a gene that can accelerate the process of synaptic pruning on imperative synapses (Aswin Sekar, et al., 2016). There also seems to be a correlation with the development of white matter portion of the brain seen in schizophrenic patients. Katherine Epstein, and Sanjiv Kumar looked at adolescent cannabis users to better understand the neurobiological mechanisms that present in a person with increased risk of psychosis. Their findings concluded that cannabis use demonstrated an adverse effect on white matter development that were associated with early onset of schizophrenia (Epstein, 2015).
Another evidence that helps researchers understand the possible link between schizophrenia and the use of cannabis is the stress- vulnerability model used in psychology. The stress- vulnerability model is defined as “the theory that a genetic or biological predisposition to certain mental disorders (e.g., schizophrenia, mood disorders) exists and that psychological and social factors can increase the likelihood of symptomatic episodes” (APA, 2019). Cannabis can be considered to be a stressor, or social factor that can start the onset of schizophrenia. If a person is predisposed for later onset of schizophrenia, adding a stressor like cannabis will increase the risk factor of early onset. Being that schizophrenia is an illness that consists of delusions and hallucinations, adding a psychoactive chemical like THC, which is found in cannabis and can cause hallucinations, it could possibly bring forth the onset of schizophrenia by the definition of the stress- vulnerability model. Everyone’s stress vulnerability is different, and it can only be theoretically applied, but it is used by psychologist to present the risk factors of stressors to certain mental illnesses (Khokhar, et al., 2017).
Despite the evidence that supports a link between schizophrenia and cannabis, there are scientist who contradict these positions and believe that people who are schizophrenic are heavy cannabis and substance users. It ultimately falls to the distinction between correlation and causation. Some researchers believe that people with psychosis are regular users of substance and aren’t clear on which came first: the disease, or the substance abuse. Research done by Leon French showed evidence that there wasn’t any change in brain thickness and development in adolescents with higher genetic risk of schizophrenia, and low risk males and females he sampled (Leon French, et al., 2015). Even though his evidence shows no correlations, scientists are still baffled as to what is the main cause in schizophrenia. This study just shows that there isn’t a link in the usage of cannabis with the thickness of brain in people, and their genetic risk of getting schizophrenia. Ian Hamilton is also a firm believer in the lack of relationship between the use of cannabis and schizophrenia. He argued against two papers written by Sven Andreasson and Wayne Hall and believed their research was flawed because of the lack of an authentic control group. They neglected to consider other risk factors that can increase the chance of psychosis, like the use of tobacco and alcohol. If participants aren’t just cannabis users, there can be confounding variables that alter the findings of studies. Hamilton thus commended Andreasson on applying more considerate models to this subject, being that he linked the disorder to the stress-vulnerability model but deems that there is still much left to consider in regard to conducting a more detail, and controlled studies when it comes to correlating schizophrenia and cannabis.
Scientists may be divided in the causation of schizophrenia due to the usage of cannabis, but knowing that there is a possible link can help create reforms to protect people from suffering with such a dreadful illness. Even though there are medications that do help with the symptoms that come about from this disorder, they are one of the drugs with the most severe side effects seen in antipsychotic medications. Some of these side effects include: drug-induced Parkinsonism, which resembles Parkinson’s disease and is one of the most commons side effects of antipsychotic medication. The person would have tremors, shuffling gait, rigidity, and lack of emotional expression. Other symptoms include tardive dyskinesia, which is characterized as repetitive involuntary movements in the face, neck and tongue. This is seen in patients that have long term treatment. It is also possible for tardive dyskinesia to persist even when patients stop using the drug. Seizures, and uncontrollable salvation, sweating are possible side effects as well (Self, 2018). Furthermore, a person who suffers from schizophrenia will have to be on medication for the rest of their lives if the symptoms of severe. Visualize having the delusion that someone is spying on you through the electrical outlet, and loud voices are screeching, and shouting at you that the people living in the sockets are spying on you and will eventually come out and kill you. In order to get rid of the persistent voices, and the feeling of being spied on, you will stuff the socket with items that cause a fire, or you would hurt yourself. This is sadly what people with schizophrenia feel. The addition of these side effects also deters people from taking their medication, making symptoms much worse, and uncontrollable. Some patients also refuse to take their antipsychotic medication because it will” harm” them or take away their “powers” when suffering from delusions of grandeur. Knowing what people go through with schizophrenia and the possibility that cannabis can increase the onset of this disease, we should be focusing on monitoring the consumption of cannabis. Especially when onset of the disease is in the late teens through 20s. Screening patients who want medical marijuana and who fall in that bracket of age for a family history in schizophrenia can possibly decrease the onset of the illness. These are small losses people can take to not increase their chances of getting schizophrenia.
Even if scientists are split on whether cannabis is a risk factor in a person developing schizophrenia, more search should be done on this subject because if there is a possibility of causation, we should be doing more deter the possible onset of an illness that can be extremely debilitating. There is a significant amount of studies that do show there is a correlation between cannabis and schizophrenia, and the possibility that it is a risk factor. With this information, we can set rules or restrictions to decrease the chances, in young adults that use cannabis heavily, it will also educate consumers on the risks and help them better understand their choices when it comes to their health.
References
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