(May 28, 2010 - Insidermedicine)

Among elderly individuals who rely on multifocal lens glasses, switching to glasses with a single lens for improving distance vision may lower the risk of falls, according to research published online ahead of print in the British Medical Journal.

Here is some information about eye changes that occur as one ages:

•    Presbyopia is a condition in which the lens inside the eye loses its ability to accomodate, making it harder to focus on objects up close. Patients may notice that they have move a book farther away to read

•    Presbyopia can be corrected with reading glasses. But if you also need glasses for distance,  a multifocal lens may be prescribed. In a multifocal lens, the top part of the lens corrects for distance, and the bottom part for different distances.

•    Aging also causes the lens to eventually become very cloudy, a condition referred to as a cataract, which may need surgery to treat

Researchers from Royal North Shore Hospital in Sydney gave vision tests to over 600 elderly wearers of multifocal lenses. All the participants had recently experienced a fall or were considered to be at high risk for falling because of their frailty. Half the participants received a pair of single lens distance glasses and were instructed to wear them while walking and participating in outdoor activities.

After following the participants up for about a year, the incidence of falls was reduced by 8% among those who received the new glasses. This effect was seen primarily among those who were accustomed to outdoor activities, however. When the single lens glasses were given to those unaccustomed to outdoor activities, their risk of falling while outside actually increased.

Today’s research suggests that elderly multifocal glasses-wearers could benefit from using single lens distance glasses while participating in outside activities, but only if they are accustomed to such activity.