Refractive error due to presbyopia is the most prevalent form of visual impairment in early mid-forties and by the age of 50yrs virtually all people have this condition [1]. Presbyopia is a visual condition in which the crystalline lens of the eye loses its flexibility, making focusing on close objects difficult [2]. To correct for presbyopia, older people are either prescribed separate single lens glasses for distant and near vision, or for convenience, a single pair of multifocal (bifocal, trifocal or progressive lens) glasses [3]. Multifocal glasses have benefits for tasks that require changes in focal length, (e.g. driving, shopping and cooking). However, multifocals also have disadvantages. Many anecdotal report have recorded that multifocals constitute a ‘danger’ for older people, particularly when walking on stairs [4] and in those with disabilities that affect gait [5]. Bifocal glasses have optical defects, such as prismatic jump at the top of the reading segment, that causes an apparent displacement of fixed objects [2,6]. The lower lenses of all types of multifocal glasses blur distant objects in the lower visual field and this factor, in particular, may represent a significant problem for older people [6,7].
One study [8] found no significant association between type of spectacles worn and the risk of hip fracture, but the type of spectacles worn at the time of the fall was not recorded and so was approximated by ‘usual’ spectacles worn.
Hence, the aim of this study is to determine whether the provision of single-lens distance glasses to elderly multifocal glasses wearers, together with recommendations for wearing them for standing and outdoor activities, can reduce falling rates over a 12 month period.
Approximately 600 community-dwelling older people (age: 65+) will be recruited.
Randomised control trial.
Demographic details including age, gender, living status, along with MMSE, number of falls in previous year, questions on vision and eyewear, and medications will be collected. Baseline and 12month- follow-up data on exercise and physical activity, fear of falling will be recorded in addition to physiological profile assessment tests.
