NEWS: Common painkillers may help prevent, slow macular degeneration: study

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Common painkillers may help prevent, slow macular degeneration: study

Helen Branswell

Canadian Press

Monday, April 25, 2005

TORONTO (CP) - Common painkillers may play a role in preventing or

slowing the progression of macular degeneration, the most common form

of age-related blindness in North America, a new study suggests. The

work by two Canadian researchers does not prove that so-called NSAIDS -

non-steroidal anti-inflammatory drugs - can prevent or stop macular

degeneration in its tracks.

But it indicates the readily available drugs - often both inexpensive

and sold over the counter - could play a role in controlling this

debilitating form of vision loss.

" The burden of scientific proof is surely not satisfied by what we've

got today. But it's promising, " said Wanda Hamilton, executive director

of AMD Alliance International, a global network of advocacy groups for

age-related macular degeneration.

" Just looking at what we've got here observationally, it's pretty

exciting. And it has the potential to hold promise for the future. We

do need to work for further studies, though, " said Hamilton after

reviewing the study.

Authors Dr. McGeer of the University of British Columbia and

Dr. Sibley of the University of Saskatchewan published their

findings in the current issue of Neurobiology of Aging.

They set out to see whether people suffering from rheumatoid arthritis

might be less likely to develop macular degeneration, because of the

high levels of NSAIDS they take to control the pain of the condition.

The idea for the study came from earlier work McGeer did to show NSAID

use was protective against Alzheimer's disease. Inflammation plays a

critical role in both Alzheimer's and macular degeneration.

The two compared macular degeneration rates in a group of Saskatchewan

patients with rheumatoid arthritis who are in an ongoing observational

study that Sibley, a rheumatologist, oversees.

" This is a good population to test the idea that anti-inflammatories

would cause a sparing of age-related macular degeneration because these

are people who are known to be heavy users of anti-inflammatory agents

and they're generally on them prior to the age of risk for macular

degeneration, " McGeer said from Vancouver.

" Rheumatoid arthritis typically comes on about a decade earlier (than

macular degeneration). "

McGeer and Sibley found the rate of macular degeneration in the

Saskatchewan rheumatoid arthritis sufferers was 10 times lower than

prevalence rates in four existing studies of similarly aged people who

did not suffer from rheumatoid arthritis. Those studies looked at

prevalence of macular degeneration in populations in the United States,

Britain, Australia and the Netherlands.

This new work is called an observational study, meaning researchers

observe the incidence of an event or condition in a group being

followed.

It is not considered as high a level of proof as the findings of a

randomized controlled trial, which tests competing treatments - or

treatment versus placebo - head to head.

But McGeer said the dramatic difference - the 10-fold decrease -

suggest work should be done to determine whether NSAIDs could be used

to treat macular degeneration, for which there currently are few

therapies.

" We don't know that it will work. But what we're saying is this is an

indication that it might, " he said.

Some work is already underway. Hamilton said the National Eye Institute

has recently completed a study looking at two types of NSAIDs combined

with photodynamic therapy, an existing treatment for wet macular

degeneration. The findings have not yet been published.

There are two forms of macular degeneration, designated as wet and dry.

Limited treatments exist for wet macular degeneration, but there are

currently none for dry macular degeneration, which makes up about 90

per cent of all cases.

" It's the commonest cause of blindness in our society. The risk of it

increases dramatically with age. We have an aging society. The

problem's only going to get worse, " Sibley said from Saskatoon.

" It's a very important problem in our society. There's no treatment for

it right now. If anti-inflammatories are at least part of the answer,

that's great. "