Older Active People Fall Less Often With Single Lens Distance Glasses

Older individuals who wear multifocal glasses and who regularly take part in outdoor activities are less likely to suffer falls if they are provided with single lens distance glasses, say Australian researchers. However, the authors of a report which appeared in the British Medical Journal (BMJ) today warn that this strategy may not be appropriate for frailer people who spend more time indoors.

Presbyopia (a progressively reduced ability to focus on objects nearby) is the most common form of impaired vision in older individuals. To address for this condition, patients 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.

For tasks that require changes in focal length, such as driving, shopping and cooking, multifocal glasses have benefits. Their disadvantage is that they can impair balance and increase the risk of falls in older individuals.

So researchers in Sydney, Australia set out to test whether giving older people an additional pair of single lens distance glasses for wearing when outdoors or in unfamiliar settings would help to reduce falls.

They studied 606 people, either at least 80 years of age or at least 65 with a history of falls. All of them used multifocal glasses at least three times a week when walking outdoors and did not use single lens distance glasses.

Study participants were randomly selected into two groups, an intervention and a control group.

After an initial examination by an optometrist, 305 intervention participants were given a pair of single lens distance glasses for wearing outdoors and in unfamiliar settings, and were told how to use them. They were also shown how multifocal glasses can increase the risk of falls.

The control participants had the same optometrist examination as the intervention group, but were not prescribed single lens glasses and received no falls prevention advice.

They were monitored for 13 months. During that time, the total number of total falls in the intervention group was reduced by 8% compared with the control group. For those who went outdoors regularly, all falls – outside falls and injurious falls – dropped by approximately 40%.

However, outside falls increased significantly for those who spent more time inside.

The intervention did not influence physical activity or improve quality of life.

Based on these findings, the authors recommend that older people who engage in frequent outdoor activities should be provided with single lens distance glasses for outside use when they are prescribed their first pair of multifocal glasses. However, those who undertake little outdoor activity should use multifocal glasses for most activities, rather than using multiple pairs of glasses.

In an accompanying editorial, Professor John Campbell and team at the Dunedin School of Medicine in New Zealand say that correcting vision can help lower the likelihood of a fall, but that any changes should be introduced gradually in a planned manner so that an individual is not overwhelmed. They also recommend good communication between doctors and optometrists when considering vision, glasses and the risk of falls.

Research: “Effect on falls of providing single lens distance vision glasses to multifocal glasses wearers: VISIBLE randomised controlled trial”
Mark J Haran, Ian D Cameron, Rebecca Q Ivers, Judy M Simpson, Bonsan B Lee, Michael Tanzer, Mamta Porwal, Marcella M S Kwan, Connie Severino, Stephen R Lord
BMJ 2010;340:c2265
Published 25 May 2010, doi:10.1136/bmj.c2265

Editorial: “Poor vision and falls”
A John Campbell, Gordon Sanderson, M Clare Robertson
BMJ 2010;340:c2456
Published 25 May 2010, doi:10.1136/bmj.c2456