Can Drug Use Cause Schizophrenia - Schizophrenia Center - fim-mdu.info
Oct 21, The links between schizophrenia and drug abuse are a hotly debated topic. A new Danish study casts their net wide and gleams new insight. Feb 14, However, some evidence suggests that a causative relationship exists between the use of certain drugs and schizophrenic symptoms. Nov 19, Nearly half of people with schizophrenia abuse drugs and/or alcohol. This often results in issues with interpersonal relationships or in other.
Dysregulated neural integration of dopamine and glutamate in the nucleus accumbcns could lead to neural and motivational changes similar to those seen in long-term substance abuse. Using functional magnetic resonance imaging fMRIJuckel et al 20 found decreased activation of the left ventral striatum, one of the central areas of the brain reward system, to be correlated with the severity of negative symptoms in medication-free schizophrenic patients.
In addition, dysfunction in the ventral striatum was detected in patients with alcohol craving.
Mathalon et al 22 compared magnetic resonance images in groups of subjects with schizophrenia, schizophrenic patients with comorbidity of alcohol dependence, and alcohol-dependent patients with those from a matched control group. Although found in all three patient, groups, gray matter deficits were greatest in the group with comorbidity, with most prominent deficits in the prefrontal and anterior superior temporal regions.
Thus, as a result of an interactive effect, comorbidity might, compound the prefrontal cortical deficits independently present in schizophrenia, as well as in alcohol dependence. Nicotine and schizophrenia Nicotine interacts with several central pathways involved in schizophrenia, such as the dopaminergic and the glutamatergic pathways in the mesolimbic areas. As a result, smokers were significantly more likely to be men, and to have had an earlier age of onset and a greater number of previous hospitalizations.
Furthermore, smokers received significantly higher doses of neuroleptics than nonsmokers. In a recent study, Weiser et al 23 investigated a sample of more than 14 adolescents followed over a period of 4 to 16 years, and found that adolescents who smoked more than 10 cigarettes per day at, initial evaluation were significantly more likely to be hospitalized for schizophrenia during the follow-up period. Thus, either smoking might, be used as self-medication of symptoms, or abnormalities in nicotinic transmission might be involved in the pathophysiology of schizophrenia.
Careful interpretation is recommended, as further investigation in this area will be necessary in order to determine the role of nicotine dependence in schizophrenic patients. Cannabis and schizophrenia During recent, years, controversial discussions have resumed regarding whether cannabis consumption might increase the risk of developing schizophrenic symptoms.
Andreasson et al 24 referred to the first, evidence that cannabis may be a causal risk factor for later schizophrenia. Several recent studies have investigated the risk factor of cannabis use for future psychotic symptoms, and research in this field has provided a growing body of evidence that the use of cannabis may be associated with increased risks of psychosis and psychotic symptoms. In particular, heavy cannabis use may accelerate or exacerbate psychotic symptoms in vulnerable individuals.
In recent, years, advances in the understanding of brain cannabinoid receptor function and the association between cannabinoid compounds and psychosis have been made. Data from a double-blind, randomized, and counterbalanced study indicate that intravenously administered dcltatetrahydrocannabinol delta 9-THC produces a wide range of transient symptoms, behaviors, and cognitive impairments in healthy individuals, resembling several aspects of endogenous psychoses.
At the age of 11 psychotic symptoms were assessed from self reports. Following the same procedure at, 15 to 18 years, the subjects were examined with regard to their cannabis use. At the age of 26, psychiatric symptoms were evaluated using a standardized interview schedule to obtain diagnostic criteria according to the Diagnostic and Statistical Manual of Mental Disorders, 4th edition DSM-IV.
Another New Zealand longitudinal study 26 investigated a cohort of people born in mid At ages 18, 21, and 25 years, sample members were administered a comprehensive mental health interview designed to assess a number of aspects of mental health and psychosocial adjustment.
In addition, at each assessment, subjects were questioned about their cannabis use. The findings of this study, based on a sample of participants, suggest, that daily users of cannabis had rates of psychotic symptoms that, were between 1.
However, critical comments do not support, these results, but emphasize that, the findings of Fergusson et al, 26 based on just 10 items from the Symptom Checklist, would raise more questions than they would be able to answer.
- Substance abuse in patients with schizophrenia
- Can Drug Use Cause Schizophrenia?
Marijuana smokers may have beliefs that, are different, from the mainstream, and thus could be suspicious of others. An important limitation, however, includes the fact that prospective studies are based on self-reported measurements of cannabis use. Overall, cannabis docs not, seem to represent a sufficient cause for the development of schizophrenia.
However, even though the majority of young people who use cannabis in adolescence do so without experiencing a harmful outcome, there are consistent findings that cannabis use does indeed increase the risk for schizophrenia and other psychotic disorders in vulnerable people. Cocaine yields to a blockade of presynaptic dopamine reuptake, producing a large increase in synaptic dopamine.
Schizophrenia risk increased with alcohol, drug abuse
This effect is blocked through dopamine receptor antagonists, and should discourage abuse. However, this may be counterbalanced through other factors, including negative symptoms and depressed mood. Based on the self-medication hypothesis, schizophrenic patients may use cocaine to counteract, extrapyramidal side effects occurring as a result of antipsychotic drug treatment.
Furthermore, cocaine may be used in order to overcome a defect in dopamine-mediated reward circuits. An important, limitation, however, involves the small sample size of 24 patients. A recent pilot study, however, provided some evidence that treatment with aripiprazole, a partial dopamine agonist with high affinity for both dopamine D2 and D3 receptors, might, possibly lower both the desire for and the use of cocaine in these patients.
Anyway, these findings need a cautious interpretation with respect to the small sample size of 10 subjects, and should be reassessed anyway using a double-blind, randomized comparison study design. Intervention and aim of treatment Since schizophrenia and substance misuse have been determined to be closely interdependent, a dual diagnosis - treatment of schizophrenia and drug abuse is needed.
Currently, research is focusing on a range of psychological strategies such as family intervention, skills training, cognitive therapy, or development of substance refusal. To date, there is a growing body of evidence that motivational enhancement interventions, which tend to alter drug use and refine skills, may be a feasible first-line intervention for substance abuse in early psychosis.
However, the main focus of treatment for these patients consists in stabilization of psychotic symptoms, hostility, and agitation. Several new antipsychotic medications, such as risperidone, clozapine, or olanzapine, have been introduced, and appear to be at least as effective as the typical antipychotics.
Therefore some atypical antipsychotics may be of benefit. Patients treated with newer agents also tend to perform better on neurocognitive measures than patients who receive traditional antipsychotic medications. However, it should be noted that newer antipsychotics also produce some adverse effects.
Although data from atypical interventions in this field are limited to those from small, mostly uncontrolled studies, atypical antipsychotics are associated with a decrease in substance abuse in schizophrenic patients.
Finally, neuroleptic medication may contribute to dysphoria and anhedonia, which might, be a consequence of impaired dopamine function in the nucleus accumbens and play an important, role in regard to comorbidity with substance abuse disorders.
Why Unhealthy Drug and Alcohol Use Often Accompanies Schizophrenia
However, careful interpretation is recommended, as further research is needed in order to investigate the effects of antipsychotics on subjective wellbeing, as well as on craving for drugs. Overall integrated treatment models that address both disorders have been found to increase retention and participation in treatment, reducing symptoms and substance use. Conclusion and future directions It has been determined that, schizophrenic patients with co-occurring substance misuse disorders are vulnerable to an increased risk of illness and injury, poorer outcomes in psychosis, and higher rates of presentation to inpatient and emergency services.
Another tremendous problem involves the high occurrence of incarceration among persons with a diagnosis of schizophrenia, who abuse substances and lack stable housing. Even though the vulnerability of persons with schizophrenia to substance abuse has been emphasized, the degree of risk and adverse consequences diversify across various studies.
Gender-specific approaches stress that young male patients are associated with a greater risk for substance abuse. However, substance use difficulties among women with schizophrenia are often insufficiently identified. Thus, it represents a great challenge that women with comorbidity of substance abuse in many cases do not obtain adequate substance-abuse treatment, and genderspecific approaches should be incorporated into treatment strategics.
Overall, substantial contributions to the understanding of the relationship between substance abuse and schizophrenia have been made, but there is still a lack of consequences in terms of appropriate intervention programs.
Thus, it appears that the issue of comorbidity is twofold, since schizophrenic patients using drugs show specific problems that demand special intervention as well as compliance with treatment; on the other hand, community facilities are often inexperienced in treating double diagnoses.
Moreover, clinics for addiction disorders might underdiagnose psychotic disorders, just, as mental health clinics may overlook co-occurring substance abuse disorders. Care assessment, methodologies in both systems address only one type of disorder. The consequences of the inability to provide adequate treatment for these patients leads to poor outcomes and hence higher costs.
However, the problem of comorbidity has obtained increasing attention in the past years, and integrated treatment models that address both disorders have been found to be most, promising.
Further research will be required in order to establish optimal psychological and antipsychotic therapy for schizophrenic patients with comorbid substance abuse. Finally, we urgently need changes in our public policies in order to develop treatment systems that meet the requirements to implement these results, and subsequently provide adequate treatment for this particular patient group. Schizophrenia, substance use disorders and medical co-morbidity.
J Ment Health Policy Econ. Substance misuse in patients with schizophrenia. The incarceration of individuals with severe mental disorders. Community Ment Health J. For example, a recent review of studies that examined schizophrenia risk for cannabis users found that people who used marijuana by age 18 were more likely to develop schizophrenia than those who did not.
Marijuana, Cannabis and Schizophrenia - fim-mdu.info
Other studies report that people who have used marijuana more than 50 times were six times more likely to receive a schizophrenia diagnosis.
Schizophrenia and Other Drugs Studies that have examined the relationship between schizophrenia and other drugs are less common.
Alcohol is the substance most often abused by people with schizophrenia. While alcohol can cause a relapse of symptomsthere is no evidence to suggest that alcohol use causes schizophrenia. And stimulants, like cocaine and amphetamines, are linked to types of psychosis, while heroin users were actually at a lower risk for developing psychoses.
Ken Duckworth, MD, medical director of the National Alliance on Mental Illness and an associate professor at Harvard Medical School in Boston, says that proving the link between schizophrenia and illicit drug use is tough. To prove conclusively that marijuana use causes schizophrenia, a researcher would have to provide marijuana to a person at risk for schizophrenia.
This is not legal, and it is unethical to knowingly expose a person to a hazardous substance. The researcher must also carefully control the person's environment, eliminating exposure to other variables that are thought to cause schizophrenia. This is neither practical nor ethical. Instead, researchers must rely on longitudinal or "cohort" studies that track a large group of people over the course of many years. Researchers periodically take medical histories and ask questions about drug use and life experiences.
The data are subject to participants' memory and willingness to disclose personal information, and the studies can take years. Despite limitations, evidence gleaned from these studies sheds light on new schizophrenia prevention strategies.
Based on the study involving the Swedish military, the researchers speculate that as many as 13 percent of schizophrenia cases could be prevented if no one used marijuana. Other studies suggest that the greatest risk is to adolescents.