Actigraphic motor activity in mild cognitive impairment patients carrying out short functional activity tasks: comparison between mild cognitive impairment with and without depressive symptoms

Abstract

Background: Individuals with mild cognitive impairment (MCI) may exhibit changes in motor activity in conducting their activities of daily living. Depression, one of the most frequent neuropsychiatric symptoms, might affect motor activity in MCI.

Objective: To assess motor activity in MCI subjects carrying out short functional activity tasks using ambulatory actigraphy. Secondly, we sought to investigate the influence of depressive symptoms on motor activity.

Methods: 20 MCI and 14 healthy subjects carried out a 30-minute standardized scenario while wearing a chest actigraph. The protocol consisted of directed activities (execution of motor tasks), semi-directed activities (execution of Instrumental Activities of Daily Living, IADL), and undirected 'free' activities. Several common assessment scales (GDS, MADRS, and NPI) were used to diagnose depression.

Results: MCI subjects had significantly reduced mean motor activity while carrying out directed and semi-directed activities, compared to healthy control subjects. No difference was found in motor activity between MCI subjects with or without depression.

Conclusion: Actigraphic measurement of motor activity during the evaluation of IADLs and motor tasks is a potential objective tool in detecting early changes in MCI. Depressive symptoms seem not to be associated with motor activity in MCI subjects.

Keywords: Actigraphy; depressive symptoms; mild cognitive impairment; motor activity.