Polysomnographic characteristics of neuroleptic-induced akathisia

To investigate nocturnal leg movement activity and other polysomnographic features in patients with neuroleptic-induced akathisia (NIA), all-night polysomnography was performed in nine patients with NIA and compared with nine healthy individuals and eight unmedicated patients with depression. Patients with NIA displayed a pattern of leg movement activity during sleep similar to healthy individuals and depressed patients. In addition, eight of nine patients with NIA exhibited 10- to 40-second bursts of increased leg muscle tone before sleep onset. Although the significance of this finding is unclear, it is possible that it may be a pathophysiological correlate of NIA.