Extrapyramidal side effects with atypical neuroleptics in bipolar disorder

To examine, in a real-world clinical setting, the risk of extrapyramidal symptoms (EPS) with atypical neuroleptics in bipolar patients.

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.

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.

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.