Multisensory Integration Predicts Balance and Falls in Older Adults

Background: Effective integration of concurrent sensory information is crucial for successful locomotion. This study aimed to determine the association of multisensory integration with mobility outcomes in aging. Methods: A total of 289 healthy older adults (mean age 76.67 +/- 6.37 years; 53% female participants) participated in a visual-somatosensory simple reaction time task. Magnitude of multisensory effects was assessed using probability models, and then categorized into four multisensory integration classifications (superior, good, poor, or deficient). Associations of multisensory integration with falls and balance (unipedal stance) were tested at cross-section and longitudinally using Cox proportional hazards models. Results: At baseline, the prevalence of falls in the previous year was 24%, and 52% reported an incident fall over a mean follow-up period of 24 +/- 17 months. Mean unipedal stance time was 15 +/- 11 seconds. Magnitude of multisensory integration was a strong predictor of balance performance at cross-section (beta = 0.11; p <.05). Of the cohort, 31% had superior, 26% had good, 28% had poor, and 15% had deficient multisensory effects. Older adults with superior multisensory integration abilities were significantly less likely to report a fall in the past year (17%), compared to the rest of the cohort (28%;.2 = 4.01; p =.04). Magnitude of multisensory integration was an incremental predictor of incident falls (adjusted hazard ratio = 0.24; p =.01), over and above balance and other known fall risk factors. Conclusions: Our study highlights the clinical relevance of multisensory integration in aging; worse visual-somatosensory integration is associated with worse balance and increased risk of incident falls.