Clozapine associated pulmonary embolism: systematic review.

Background

Clozapine is a second-generation antipsychotic used in refractory schizophrenia. Clozapine can lead to pulmonary embolism (PE) by various mechanisms including immobility, weight gain and increased platelet aggregation.

Objectives

We performed a systematic review on published cases of PE associated with clozapine.

Methods

Comprehensive search of Medline, Embase and Cochrane library was done for relevant articles from inception until June 2017

Results

Total of 34 cases from 24 articles were included in the analysis. The mean age was 43.2 years with male predominance (63.6%). The mean dosage of clozapine was 281.4 mg daily. Duration of intake ranged from few days to many years. Nearly half of patients (47.82%) had no other co-morbidities for PE other than clozapine. For those reporting treatment, anticoagulation was chosen in 80%, thrombolysis in 10% and inferior vena cava filter placement in 5%. Mortality was 36.36% with three dying on presentation and an additional 9 dying during the follow-up period. Of the 18 patients in which follow-up data of clozapine were available, the drug was discontinued in 14 patients.

Conclusion

PE can occur at doses lower than usual dose of clozapine (300 mg daily). It is important to consider this association especially in patients with no other risk factors for PE.