Objective: To examine, in a real-world clinical setting, the risk of extrapyramidal symptoms (EPS) with atypical neuroleptics in bipolar patients.
Methods: The authors assessed 51 individual patient trials of atypical neuroleptic agents (17 risperidone, 13 olanzapine, 11 quetiapine, 8 ziprasidone, and 2 aripiprazole) in 37 bipolar patients (type I or type II). Risk of EPS was assessed using the Abnormal Involuntary Movement Scale, Barnes Akathisia Rating Scale, and the Simpson-Angus Scale. Mean duration of treatment was 25.5 weeks (range 3-107 weeks) and 60.8% of patients were female.
Results: 62.7% of trials resulted in moderate to severe EPS. EPS and discontinuation frequencies were similar between specific neuroleptic agents or between high potency (risperidone/ziprasidone/aripiprazole; 52.9%, 27/51 trials) and low potency (quetiapine/olanzapine; 47.1%, 24/51 trials) agents. In a multiple regression model adjusted for confounders, akathisia was less common with low potency agents. Younger age was associated with more akathisia. 31.4% (11/35) of trials discontinued due to side effects. 7.8% (4/51) of trials led to mild de novo tardive dyskinesia.
Conclusions: Over one-half of bipolar patients experienced EPS in this real world clinical setting. This rate is much higher than the 5-15% range reported in clinical trials, suggesting potential problems with clinical trial generalizability.