Motion Analysis in Delirium: A Novel Method of Clarifying Motoric Subtypes

Abstract

The usefulness of motor subtypes of delirium is unclear due to inconsistency in subtyping methods and a lack of validation with objective measures of motor activity levels. We studied patients with hyperactive, hypoactive, and mixed presentations of delirium were studied with 24-h accelerometer-based monitoring. The procedures were well tolerated and motor presentations were readily distinguished using the accelerometer-based measurements. The system was capable of identifying static versus dynamic activity and the frequency of changes in posture. Electronic motion analysis concurs with observed gross movement and can distinguish motorically defined subtypes according to quantitative and qualitative aspects of movement.

Keywords:

• Accelerometry
• Delirium
• Motion analysis
• Motor
• Subtype

Acknowledgments

This study was supported through departmental funds at Limerick Mental Health services. Dr Meagher has received research grant funding from Astra-Zeneca and has acted as a advisory consultant for Pfizer, Eli-Lilly, Bristol-Meyers, and Janssen Pharmaceuticals as well as receiving travel support from Smith-Kline Beecham, Eli-Lilly, Astra-Zeneca, Novartis, Wyeth, and Bristol-Meyers Pharmaceuticals Ltd.

The authors would like to thank the staff at Milford Hospice for their support in patient identification and assessment during this study and Analog Devices BV, Limerick, Ireland, for the supply of accelerometer devices.