ABSTRACT
PURPOSE/BACKGROUND: Clozapine clearance is influenced by sex, smoking status, ethnicity, coprescription of inducers or inhibitors, obesity, and inflammation. In 126 Beijing inpatients, we measured repeated trough steady-state serum concentrations and identified 4% (5/126) who were phenotypical poor metabolizers (PMs); none were ultrarapid metabolizers (UMs). They were defined as being 2 SDs beyond the means of total clozapine concentration/dose ratios stratified by sex and smoking. Using this definition, this study explores the prevalence of PMs and UMs using data from 4 already published Asian samples. Three samples were East Asian (Beijing 2, Taipei, and Seoul); one was from South India (Vellore). FINDINGS/RESULTS: The prevalence of phenotypical PMs ranged from 2% to 13%, but inflammation was not excluded. The prevalence was 7% (14/191) for Beijing 2, 11% (8/70) for Taipei, 13% (9/67) for Seoul, and 2% (2/101) for the Vellore sample. Five phenotypic PMs appeared to be associated with extreme obesity. Phenotypic UM prevalence ranged from 0% to 1.6% but may be partly explained by lack of adherence. A Vellore phenotypic UM appeared to be associated with induction through high coffee intake. IMPLICATIONS/CONCLUSIONS: Approximately 10% of Asians may be clozapine PMs and may need only 50 to 150 mg/d to get therapeutic concentrations. Future studies combining gene sequencing for new alleles with repeated concentrations and careful control of confounders including inhibitors, inflammation, and obesity should provide better estimations of the prevalence of phenotypic clozapine PMs across races. Clozapine UM studies require excluding potent inducers, careful supervision of compliance in inpatient settings, and multiple serum concentrations.
Subject(s)
Antipsychotic Agents/metabolism , Asian People/ethnology , Clozapine/metabolism , Coffee/metabolism , Inflammation/metabolism , Obesity/metabolism , Adult , Beijing/ethnology , Female , Humans , India/ethnology , Male , Prevalence , Republic of Korea/ethnology , Taiwan/ethnologyABSTRACT
Background: Although cannabis use has been linked with schizophrenia in a dose-response pattern, to our knowledge, the relationship between cannabis and schizophrenia has rarely been reported in Asian population. Aim: We compared the clinical characteristics and psychotropic prescription patterns between cannabis users and non-users among Asian patients with schizophrenia. Moreover, we aimed to identify the independent correlates of cannabis use in these subjects. Methods: We performed the analysis of the data from the Research on Asian Psychotropic Prescription Patterns for Antipsychotics (REAP-AP), a collaborative consortium survey used to collate the prescription patterns for antipsychotic and other psychotropic medications in patients with schizophrenia in Asia. We included 132 schizophrenia patients in the group of lifetime cannabis use and 1756 in the group that had never used cannabis. A binary logistic model was fitted to detect the clinical correlates of lifetime cannabis use. Results: Adjusting for the effects of age, sex, geographical region, income group, duration of untreated psychosis, and Charlson comordity index level, a binary logistic regression model revealed that lifetime cannabis use was independently associated with aggressive behavior [adjusted odds ratio (aOR) = 1.582, 95% confidence interval (CI) = 1.006-2.490, p = .047] and with long-acting injectable antipsychotic treatment (aOR = 1.796, 95% CI = 1.444-2.820, p = .001). Conclusion: Our findings indicate a close link between lifetime cannabis use and aggressive behavior. The use of long-acting, injectable antipsychotics preferentially treats the aggressive behavior cannabis users among patients with schizophrenia in Asia, especially, the South or Southeast Asia.
Subject(s)
Aggression , Antipsychotic Agents/administration & dosage , Antipsychotic Agents/therapeutic use , Cannabis/adverse effects , Marijuana Smoking/adverse effects , Schizophrenia/drug therapy , Adult , Asia/epidemiology , Asian People/psychology , Female , Humans , Logistic Models , Male , Marijuana Smoking/epidemiology , Marijuana Smoking/psychology , Odds Ratio , Psychotropic Drugs/administration & dosage , Psychotropic Drugs/therapeutic use , Schizophrenia/epidemiology , Surveys and QuestionnairesABSTRACT
BACKGROUND: Cancer is a serious public health problem worldwide, and its relationship with affective disorders is not clear. Aims To investigate alcohol- and tobacco-related cancer risk among patients with affective disorders in a large Taiwanese cohort. METHOD: Records of newly admitted patients with affective disorders from January 1997 through December 2002 were retrieved from the Psychiatric Inpatient Medical Claims database in Taiwan. Cancers were stratified by site and grouped into tobacco- or alcohol-related cancers. Standardised incidence ratios (SIRs) were calculated to compare the risk of cancer between those with affective disorders and the general population. RESULTS: Some 10 207 patients with bipolar disorder and 9826 with major depression were included. The risk of cancer was higher in patients with major depression (SIR = 2.01, 95% CI 1.85-2.19) than in those with bipolar disorder (SIR 1.39, 95% CI 1.26-1.53). The elevated cancer risk among individuals ever admitted to hospital for affective disorders was more pronounced in tobacco- and/or alcohol-related cancers. CONCLUSIONS: Elevated cancer risk was found in patients who had received in-patient care for affective disorders. They require holistic approaches to lifestyle behaviours and associated cancer risks.