Akathisia and pseudoakathisia: Clinical observations and accelerometric recordings

Background: Akathisia is a common side effect of neuroleptic treatment that is diagnosed on the basis of clinical observations. Its definition is regarded as complex and controversial. Thus, for example, while some authorities see akathisia as strictly an abnormal subjective state, others require the inclusion of specific repetitive movements. The present study suggests that the addition of objective accelerometric recordings to standardized clinical observations may increase the validity of this diagnosis. Method: Sixteen chronic schizophrenic patients, treated with various neuroleptic medications, were diagnosed as suffering from akathisia. The diagnosis was based on detailed clinical observations performed according to accepted diagnostic criteria. All patients underwent repeated accelerometric recordings following the onset of akathisia. Results: While most subjects suffered from lower limb akathisia, 5 patients demonstrated the involvement of other body segments. Akathisia most frequently appeared while the patients were seated. The abnormal movements were regular, nonparoxysmal, and intermittent. Most patients suffered from a tardive disorder. The accelerometric recordings demonstrated in all cases a constant and regular wave form, frequency (below 4 Hz), and amplitude. The findings were reproducible, i.e., similar patterns appeared in several recordings of the same patient during the abnormal movements. Conclusion: Extensive and detailed clinical evaluations reveal that akathisia is not necessarily associated with restless pacing. Rather, the syndrome may include periodic, regular, and stereotyped movements, appearing in different body segments. Accelerometric recordings seem to confirm the clinical diagnosis of akathisia, demonstrating the existence of a constant wave form, frequency, and amplitude. In addition, these techniques may distinguish between akathisia and other disorders e.g., neuroleptic-induced tremor or tardive dyskinesia.