Surveillance of drug overdose and identification of its risk factors by a multivariate analysis using the Japanese Adverse Drug Event Report database

Data Mining for Risks of Clozapine Side Effects, Including Neutropenia, Associated with Lithium Carbonate Administration: Analysis Using the Japanese Adverse Drug Event Report Database

BACKGROUND AND OBJECTIVE

Clozapine use is associated with development of neutropenia, and lithium carbonate may be co-administered to reduce this risk; however, this has not yet been adequately investigated. The present study examined whether lithium administration is associated with the risks of clozapine side effects, including neutropenia.

METHODS

Data on patients taking clozapine, extracted from the Japanese Adverse Drug Event Report (JADER) database, were analyzed. Patients who developed clozapine side effects were identified by the Standardized Medical Dictionary for Regulatory Activities Queries. The relationship between the use of lithium and risk of clozapine side effects was examined using logistic regression analysis.

RESULTS

The use of lithium was reported in 530 out of 2,453 clozapine users. Hematopoietic leukopenia, convulsion, and noninfectious myocarditis/pericarditis developed in 109, 87, and seven lithium-treated patients, and in 335, 173, and 62 untreated patients, respectively. Univariate analysis showed no relationship between lithium administration and the risks of hematopoietic leukopenia (adjusted odds ratio (aOR) 1.11; 95% confidence interval (CI) 0.98-1.25), and the association with the risks of convulsion (aOR 1.41; 95% CI 1.23-1.62) and noninfectious myocarditis/pericarditis (aOR 0.63; 95% CI 0.43-0.94). Multivariate analysis revealed that lithium use was independently associated with the risks of convulsion (aOR 1.40; 95% CI 1.21-1.60) and noninfectious myocarditis/pericarditis (aOR 0.62; 95% CI 0.41-0.91).

CONCLUSION

The risks of seizure and myocarditis, but not of neutropenia, in clozapine-treated patients may be altered by lithium. Although the JADER database is based on spontaneous reporting, the present results warrant further study.

Risk factors for suicidal behavior/ideation and hostility/aggression in patients with bipolar disorders: An analysis using the Japanese Adverse Drug Event Report database

The present study attempted to identify risk factors for suicidality and hostility/aggression in patients with bipolar disorders. Data on 3521 patients were extracted from the Japanese Adverse Drug Event Report (JADER) database. There were 134 reports regarding suicidal behavior/ideation, and 129 patients were judged to have it. Standardized Medical Dictionary for Regulatory Activities queries indicated that 248 adverse drug events pertained to hostility/aggression, and 218 patients were considered to show hostility/aggression. A multiple logistic regression analysis revealed the association of the risk for suicidal behavior/ideation with bipolar II disorder [adjusted odds ratio (aOR): 4.55, 95% confidence interval (CI): 1.90-10.9], male sex (aOR: 1.23, 95% CI: 1.02-1.48), age <50 years (aOR: 1.75, 95% CI: 1.43-2.15), the administration of aripiprazole (aOR: 1.27, 95% CI: 1.00-1.60), and akathisia (aOR: 3.05, 95% CI: 1.80-5.18), while lithium carbonate decreased its odds (aOR: 0.664, 95% CI: 0.537-0.821). The risk of hostility/aggression was associated with male sex (aOR: 1.22, 95% CI: 1.06-1.40), lithium carbonate (aOR: 0.823, 95% CI: 0.710-0.953), and carbamazepine (aOR: 0.693, 95% CI: 0.500-0.961). No association between suicidal behavior/ideation and hostility/aggression was recognized. The present study proposes factors related with suicidal behavior/ideation and hostility/aggression in patients with bipolar disorders using the JADER database. Lithium carbonate appeared to decrease the risks of suicidal behavior/ideation and hostility/aggression in patients with bipolar disorders, and akathisia may be associated with the former risk. Further studies are required to evaluate the identified signals.

Relationship between lithium carbonate and the risk of Parkinson-like events in patients with bipolar disorders: A multivariate analysis using the Japanese adverse drug event report database

The present study attempted to identify risk factors for Parkinson-like events using the Japanese adverse drug event report database. A total of 3521 patients with bipolar disorders were extracted from the database, and Parkinson-like events were detected in 111 (3.15%) using the standardized Medical Dictionary for Regulatory Activities queries. A multiple logistic regression analysis identified age ≥50 years and the use of sodium valproate or aripiprazole as risk factors. Lithium carbonate was not associated with an increased risk of Parkinson-like events, but was related to these events in patients taking sodium valproate.