Visual field dependence, sensorimotor function and falls in community dwelling older people

Abstract

BACKGROUND:Moving visual fields can have strong destabilising effects on balance, particularly when visually perceived motion does not correspond to postural movements. This study investigated relationships between visual field dependence and sensorimotor function and falls in older people.

AIM:To determine whether sensorimotor function deficits are associated with visual field dependence (VFD), and whether VFD is a risk factor for falls and fall-related injuries in older community living people.

METHOD:684 community-dwelling adults aged 75 years and older undertook a roll vection test (i.e. attempted to align a rod to the vertical while exposed to a rotating visual field). Participants also underwent a series of sensorimotor function tests and were followed up for falls for 12 months with monthly questionnaires.

RESULTS:131 (24%) participants aligned the rod in the roll vection test > 6.5⁰ from the vertical and were categorised as being VFD. More women than men were VFD and participants with VFD had reduced lower limb strength, increased sway in a test reliant on vestibular function (standing on a foam mat with eyes closed), and poorer dynamic stability. Participants with VFD also experienced significantly more falls and injurious falls in the follow-up period compared to participants without VFD when adjusting for age, sex and a composite physiological fall risk score.

CONCLUSION:VFD may be associated with reduced muscle strength and impaired vestibular function in older people. As VFD was identified as an independent risk factor for falls, incorporating strategies to address this condition may improve the efficacy of fall prevention interventions for older people.