Structured Grocery Shopping Differs Between Older Adults with Mild Cognitive Impairment and Cognitively Unimpaired

Research Objectives: To investigate the activity differences in a structured grocery shopping task between older adults with mild cognitive impairment (MCI) and cognitively unimpaired (CU).

Design: Case-controlled study, single visit. Participants performed five trials of a structured grocery shopping task. Each trial consisted of using a shopping basket to collect eight items in the order in which they appear on a shopping list. Participants were outfitted with an action camera and four inertial measurement units (IMUs) at the lumbar spine, posterior cranium, and top of each foot.

Setting: Simulated physical grocery in an academic research laboratory.

Participants: Participants included 15 with MCI of mean age 69 years (SD 4.2), and 15 CU of mean age 66.6 years (SD 3.7). Age was similar between groups (p=0.07). MCI was diagnosed by a neuropsychologist, and CU by the Montreal Cognitive Assessment (>26). Participants were a volunteer sample recruited from the local community and academic hospital settings.

Interventions: Not Applicable

Main Outcome Measures: Whole trial analysis variables were used as outcome measures in this study. Accelerometer data was analyzed with an actigraphy-based calculation producing variables of total activity and total activity per minute accelerometer counts at the lumbar spine and head. Gyroscope data variables included total degrees of movement and angular velocity per minute at the lumbar spine and head. Baseline comparative measures included age and gait speed.

Results: Activity counts per minute at the lumbar spine (p=0.0267 d=0.260) and angular velocity per minute at the head (p=0.006, d=0.344) are lower in those with MCI. The total activity counts at the lumbar spine (p=0.818), total degrees of head turns (p=0.169), and average gait speed (p=0.3979) were not different between groups, however. This indicates that while those with MCI have similar overall whole trial activity during structured grocery shopping, the intensity of activity and head turns begin to slow.

Conclusions: This study provides initial evidence that objectively measured activity during a real-world cognitive overlay, such as grocery shopping, differs between those with MCI and those with CU. Wearable technology may be a promising digital biomarker of cognitive decline by detecting performance differences in important instrumental activities of daily living, such as grocery shopping. Future studies are needed in community grocery stores to assess free-living IADLs to determine if grocery shopping activity can be used as a digital biomarker of cognitive decline.

Author(s) Disclosures: The authors have no disclosures.