Cognitive Impairment Decreases Postural Control During Dual Tasks in Geriatric Patients with a History of Severe Falls

Objectives: To investigate the influence of dual tasks, cognitive strategies, and fear of falling on postural control in geriatric patients with or without cognitive impairment and with a history of falls resulting in injury. Design: Experimental three‐group design. Setting: Geriatric hospital. Participants: Twenty young healthy adults (mean age±standard deviation=25.4±4.4), 20 geriatric patients with a history of severe falls without cognitive impairment (mean age=82.6±5.5, mean Mini‐Mental State Examination (MMSE) score=27.8±2.0) and 20 geriatric patients with a history of severe falls and cognitive impairment (mean age=83.2±5.5, mean MMSE=19.2±3.3). Measurements: Motor performance: sway area and lateral and anterior‐posterior sway angles. Cognition: semiautomated calculation steps (serial 2 forward) and nonautomated calculation derived from MMSE (serial 7 retro). Motor and cognitive performances were examined as single and dual tasks. Strategy decision, fear of falling, and subjective perception of motor and cognitive performance were assessed as covariates for dual‐task performances. Results: Motor performance decreased significantly during all dual tasks in geriatric patients with cognitive impairment and a history of falls resulting in injury. Cognitive performance was different depending on the task and group. Choice of cognitive strategies or fear of falling did not influence the dual‐task performances. Conclusion: Even simple additional tasks substantially decrease postural stability due to attention‐related cognitive deficits in cognitively impaired geriatric patients with a history of severe falls. The findings may help to explain the increased incidence and severity of falls in geriatric patients with cognitive impairment and a history of falls resulting in injury.