Etiology on Schizophrenia and the influence that drug use has on it
Introduction
Schizophrenia refers to a severe and chronic disorder that normally affect a person’s thinking, feeling and acting and it has known to be very disabling even though it is not common as compared to other mental illnesses. It has been shown to affect about 7 to 8 people out of 1000 in their lifetime (Molloy et. al 2011). People suffering from this disorder may be able to hear voices or even see things that are not there, believe other people can read their minds, control their thoughts and see them as plotting to harm them. There is not surety on what causes schizophrenia but scientists believe that the disorder results from a combination of different factors ranging from genetics, environmental effects and brain chemistry. There certain factors that have been seen as increasing the risk of developing this condition and these relate to the aforementioned aspects in addition to certain triggers from the environment, health conditions such as complications in pregnancy and birth and even some self-destructive habits such as drug abuse. Drug use has also been largely related to the development of this condition especially given that they can trigger psychosis in those individuals who are prone to develop this mental condition. Increasing evidence shows that the illicit use of drugs can be one of the environmental factors leading to schizophrenia. The disorder has various symptoms that are divided into cognitive, positive and negative ones. The positive symptoms include hallucinations, thought and movement disorders and these include psychotic behaviors not observed in normal people. The negative emotions concern disruption to normal behaviors and emotions. Cognitive symptoms appear as subtle in some individuals but severe in other patients ethos may notice changes in their thinking aspects and memory. There are various limitations on the studies carried out on the causes of schizophrenia and the various treatment methods for it which calls for more scientific research on these areas
Etiology on Schizophrenia
It has long been known by Scientist that schizophrenia runs into families at times and that it in general population , it can occur in less than 1 % , but those individuals with first degree relative of this illness such as brothers , sisters and even parents , it occurs in about 10 percent of them. Even those people with second-degree relative such as grandparents, cousins and uncles suffering from the illness have a higher possibility of developing it than the general population (Cannon et. al 2000). In addition, there is a higher risk for a person who has an identical twin suffering from schizophrenia and there is about 40-65 % chance of such individuals to develop the disorder. Even though such genetic relations are quite strong, some individuals with schizophrenia do not have close relatives with this illness and conversely, individuals with family members having the condition are not affected by it themselves (Razali et. al 2013). The various studies carried out has led scientist s to conclude that various genes contribute to more risk of developing schizophrenia , but no one gene can be said to cause the illness by itself(Cannon et. al 2000).
Research done recently has in fact shown that individuals with this disorder seem to have high levels of genetic mutations that are rare. These researchers have also identified a certain gene (C4) that increases the schizophrenia risk and have even noted a theory that can explain how the gene may lead to this devastating mental disorder(Sekar et. al 2016). The C4 gene seems to be involved in the elimination of the link between neurons through a process referred to as synaptic pruning which occurs naturally in human during the teen years. There is a possibility that improper pruning of the neural connections may results to schizophrenia development as speculated by the researchers. This, they assert, would provide an explanation as to why the symptoms of this disorder appear mist of the times during teen years. Previous studies have shown that one of the significant genetic predictors of individual’s risk of the disorder was found in a DNA region that is found on chromosome 6(Sekar et. al 2016). This new studies just focused on complement component 4 region – C4- that is known to relate to the immune system. By use of samples from postmortem human brains, it was found that differences in various C4 gene copies in people and gene length could be used in the prediction of how the gene was active within the brain. Attention was then turned towards genome database where information about the gene in thousands of people with the disease and others without the disease to estimate its activity. It was found that there was a correlation between C4 activity and risk of the person developing schizophrenia (Sekar et. al 2016). The higher the activity level the greater the risk. This relation between C4 activity level and the risk of developing the illness was also found in mice experiments. Previous studies have found that individuals with schizophrenia have less synapsis in specific areas of the brain than people not suffering from this condition (Sekar et. al 2016). These new findings provide clearer evidence for a cellular and molecular mechanism of loss of synapses in the condition.
In other research that involved neuroimaging studies , evidence have been provided that the abnormalities in the brain structure can be seen early in the development of schizophrenia before the antipsychotic treatment and that the person with a risk of developing psychosis indicate alterations of the brain as they transit to psychosis .Moreover, follow up information in the research indicated that cognitive deficits can be found as early as when the individuals are in first grade , and who are destined to develop the condition in future. It is worth noting that most of these people demonstrate sensory and motor abnormalities before they are exposed to antipsychotic medications (Van Os & McGuffin, 2003).
Another issue that has been associated with the risk of developing the schizophrenia is the effect of traumatic injury of the brain. The results of the study indicated that head trauma is likely to increase the risk of schizophrenia development. People who have suffered from brain injury and hence the following traumas have a more chance – 1-6 times – of developing the condition in comparison to people who have not experienced such injuries (Malaspina et. al 2001). The traumatic injury of the brain may be due to blow or jot to the head, or an injury whose impact penetrate through the skull. The symptoms for the injury can be light such concussion or even severe like amnesia. This kind of trauma has been known to increase the risk of other psychiatric disorders such as anxiety disorders, personality change and disorder of substance use. The research involved analyzing about nine research work done previously that comprised of participants who have a history of suffering from traumatic brain injury and other participants from the public with no history of this injury (Sachdev, Smith & Cathcart, 2001). In this case , individuals who had close relatives having the schizophrenia and had suffered the traumatic brain injury, were 2.8 more likely to develop the illness than the people who had to suffered the trauma (Molloy et. al 2011). However, this risk didn’t increase for people with more severe injuries of the brain which may indicate that other factors like trauma location are more significant in regard to the risk of schizophrenia. A trigger such as traumatic brain injury cans also results to genes that predispose people to this condition, although it can also unmask the underlying of this condition (McAllister et. al 2001).
The above discussion provides evidence that schizophrenia is highly genetic and runs in families most of the times. Apart from the influence of environmental factors to the genome, research has associated the condition to small differences in DNA at over 100 distinct locations on the genome, which human’s complete DNA set. However, most of the locations can be found lying outside the actual genes and hence, their role in schizophrenia etiology remains unclear (Karayiorgou, Simon & Gogos, 2010). Other study analysis on the genome for other diseases has shown similar results. In various cases, the involved non-gene locations highlighted in the studies have become to be referred as regulatory regions whose purpose is to enhance or even repress activities of nearby genes on genome. The cortex cells were used in the study since schizophrenia affects cortical development and the mapping of these cells showed that many of sites linked to the condition in previous studies come into contact with known genes as the brain is developing (Grozeva et. al 2010). Those genes that are linked to the disease in the research various receptors in brain cells that become activated by neurotransmitter acetylene and this imply that differences in receptors’ functions can facilitate the development of schizophrenia.
Research has also shown that children who are born to mothers who experienced pregnancy and delivery complication have a higher risk of developing schizophrenia (Cannon et. al 2002). The various obstetrical complications that are linked to this condition include diabetes, bleeding retardation in fetal growth and prematurity, congenital malformations and rhesus incompatibility. In some cases, individuals who start developing schizophrenia before they reach 22 years of age were found to be likely to have a history of complicated cesarean delivery and even abnormal presentation during birth (Schmitt, Hasan , Gruber & Falkai, 2011). Those children who are born through the Caesarean section may be more likely to suffer from this condition later in life and this research linked the child birth methods and later mental health. This could be due to the fact that caesarean births were not exposed babies to surge hormones that are normally present during the vaginal birth (Jones et. al 1998).
Another complication during birth involves asphyxia, which relates to lack of oxygen during delivery which increases the risk of a person developing the condition in their adulthood. It relate to the link between neonatal and fetal central nervous system which is reported to cause schizophrenia. Other risk factors include those that require the baby to remain longer in the health facility such as delayed weight gain after birth and low weight at the time of birth (Clarke at.al 2011). In addition, pre-eclampsia which relates to being small for that gestational age and even short gestation also indicated mores risk for developing the condition even though they were not significant statistically. However, while the research adjusted for various likely confounding factors like other obstetric complications, social class and psychotic illness maternal history , the only remaining significant factor that increased schizophrenia was the asphyxia signs during birth (Suvisaari, e. al 2013). It has been argued that though the casual pathways may be difficult to understand especially given that obstetric complications are linked most of the times, the various disorders like pre-eclampsia can affect the supply of nutrients such as oxygen and glucose and thereby interfering with the development of the brain.
On the other hand, a child with a normal development can experience somehow short-term disturbance during the birth due to hypoxia. Due to hypoxic damage of the brain, there is a reduced quantity of cortex and hippocampus cells in the individual suffering from schizophrenia and with obstetric complications history (Jablensky et. al 2005). The retardation of fetal growth lead to children who are born overweight and an association has been made between the schizophrenia cases patients and such complications. The genetic factors come into play, where the retardation of fetal growth is related to genetic factors since those mothers with schizophrenia are more likely to bear children with low birth weight. Almost all factors that affect the fetal development will in turn affect its health, hence understanding this information form a pathogenesis point of view may not be informative. It could be said that the retardation of fetal growth is one of the earliest and major indication of schizophrenia neuro-developmental trajectory which comprises the various symptoms of the disease such as abnormal performance in relation to language, motor and cognitive ability from the time of birth and throughout the patients’ childhood (Curran et. al 2015).
Schizophrenia and use of drugs
Research has shown that almost half of all individuals that have been diagnosed with schizophrenia are drug and alcohol users. The rate is about four times rate of the larger population alcohol and drug use. Despite such statistics many health practitioners and researchers in mental health do not relate the abuse of drugs to the inset of this condition. Part of the research evidence tends to show that there is a causative relationship between the schizophrenic symptoms and the consumption of specific drugs (McCREADIE, 2002). For instance those people who are have genetic risk factors for this condition may experience active cases of this illness especially due to use of hallucinogenic drugs. For marijuana , the major ingredient that is also active - Tetrahydrocannabinol have a strong impact on the brain’s prefrontal hippocampus and cortex which play a key role in the ability of an individual to access memories and make sound judgment and these brain structures are normally altered in case of schizophrenia (McCREADIE, 2002). When people who are mentally sound use marijuana, they experience similar disorientation or function alteration and thereby developing short-term versions of some symptoms that are linked to schizophrenia. In addition, people who are biologically predisposed towards this condition have a higher risk of developing it, especially the young ones. This increased risk relate to the individuals who have inherited the variant genes related to this disposition and who use the street drugs and alcohol especially when teenagers. At that tender age, the human brain is rapidly developing and it is specifically vulnerable.
This shows a critical adolescence period that a person is quite vulnerable showing the impact of the drug as schizophrenia. It is likely to bring about earlier development of the condition than it would have otherwise developed. Many individuals using the drugs experience years of normality before they succumb later to psychosis commonly associated with schizophrenia; and for men it happens earlier than in women. This shows that the heavy abuse of hallucinogenic drugs can therefore be a major trigger for schizophrenia but it seems that a person has be genetically predisposed towards the condition’s development for this to take place (Kahn et. al 2008). In addition, evidence suggests that those people with the condition but are responding to provided treatment may experience an episode due to these drugs. Substance can lead to reduced effectiveness of the treatment and in case of alcohol the impact can be very outstanding. The high frequency of substance use occurring in people with schizophrenia is associated with more risk of injury and illness. Other than abnormal cognitive functioning when a person is intoxicated, the misuse of these drugs is known to result to poorer outcomes in the condition, higher frequency if patients’ admission and even emergency cases (Di Forti, 2014). This indicates that there the abuse of drugs for those people with schizophrenia acts as a great obstacle to providing effective treatment for these individuals. There are also cases of the patients suffering from this condition using drugs for the purpose of self-medication. They use the drugs and alcohol to deal or alleviate various symptoms that are associated to schizophrenia; the drug abusers end up in a status where it is difficult to provide proper treatment (Di Forti, 2014).
Conclusion
Schizophrenia is caused by a myriad of factors which have been related to genetic or environmental factors. The genetic factor factors involve the inherited predisposition genes for some of the individuals who have first degree relative with a history of this condition. Research has also shown that the condition also develops in individuals who do not have any close family member with a history of schizophrenia which complicates the research on finding the real cause of the disease. Recent research has suggested that a particular gene – C4- is responsible for the development of this condition. The other factors that have been shown to lead to this condition includes complications during pregnancy and delivery; and traumatic head injury that bring about other behavioral , psychotic and even drug use disorders. The use of drug has been shown to lead to earlier schizophrenia development for those people who are pre-disposed and reduces the effusiveness of treatment for this condition.
Strength and weaknesses
The various researches that have been done on etiology of Schizophrenia and effect of drug use on it have various limitations which include the biases in the selection of various controls and lack of enough sample participants in the studies. In addition, there is lack of large replication of findings especially those relating to genes relating to this condition. In addition, the studies do not fully show how drug use causes schizophrenia .There is need for further research especially on whther drug use causes this condtion or it is just a risk factor. However, the implications of this research are that it helps to link the various causes of schizophrenia, the effect of drug abuse as a causation aspect and its effect on treatment. No single factor that should be overlooked.
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