Psychiatry Research EG

One hundred schizophrenic patients followed up in the outpatient department of Ain Shams University Psychiatric Institute (Cairo, Egypt) were studied for the problem of substance abuse. Twenty six percent of those patients were found to fulfill DSM-IV criteria for substance abuse. The most commonly abused substances were anti-parkinsonian drugs followed by cannabinoids, opioids, and benzodiazepines. Significant risk factors for abuse included male gender, high level of depression, smoking, and premorbid personality, with no significant association regarding schizophrenia subtype or neuroleptic drug dosage. More focusing and search for substance abuse is recommended as an important step in evaluating schizophrenic patients. Comorbidity of schizophrenia and substance related disorders is common, although the implications of substance abuse in schizophrenic patients are unclear. 1 In general, such comorbidity is an indicator of poor prognosis in schizophrenia. 2 It has been estimated that about 30-50% of schizophrenic patients may meet the diagnostic criteria for alcohol abuse or dependence. Schizophrenic patients have a 3-fold risk of developing alcohol dependence, which may lead to worsening of positive symptoms, out of non compliance with medication. 3 Also, in schizophrenia, there may be an increased family history of alcoholism. 4 Apart from alcohol, stimulant abuse appears also to be common in schizophrenia. 5 Among the most commonly abused drugs are cannabis and cocaine. 6 Although not formally considered as substance abuse, cigarette smoking appears to be much more common in schizophrenic patients than in any other mental disorder, with a prevalence reaching up to 75%. It is usually associated with the use of high doses of neuroleptics, probably due to enhanced metabolic rate, and at the same time associated with decrease in drug related parkinsonian side effects, possibly because of nicotine-dependent activation of dopamine neurons. In other words, schizophrenic patients may smoke or take substances in an attempt to medicate their unwanted side effects. 7 Several theories have been put to explain such comorbidity of schizophrenia and substance abuse, including the self-medication hypothesis and the biologic vulnerability hypothesis.8 Diagnosing substance abuse in psychiatric patients and diagnosing psychiatric disorder in patients with substance abuse, are both not easy clinical tasks. Adding elements of structured interviews to clinical assessment may be of some benefit. 9