TORONTO -- Doctors should avoid screening patients age 65 and older for mild cognitive impairment unless they have symptoms like memory loss, the Canadian Task Force on Preventive Health Care advises in updated guidelines.

A review of international studies by the task force found there is no evidence that testing for the condition in seniors without signs of diminished cognitive function is beneficial -- and it may have possible harms.

Dr. Kevin Pottie, chairman of the task force working group that updated the 2001 guidelines, said up to one in four patients given standard cognitive tests are misdiagnosed as having the condition.

"So we think it's important not to just lightly look for it everywhere because people start to change their lives, maybe where they're living, giving up jobs, and there's a lot of anxiety created," Pottie said from Ottawa.

"And mild cognitive impairment may not be related to dementia. It could be related to another disease, it could be related to depression."

While some people with mild cognitive impairment go on to develop dementia, others remain the same and some actually improve over time, he said.

Pottie said there's no evidence that drugs being used to slow the progression of Alzheimer's and other forms of dementia lead to improvement in memory or other mental functions in people with mild cognitive impairment.

"There's been a lot of hype and hope with new drugs coming on the market. But our systematic (research) review found no real benefits, and there could be harms from side-effects," he said.

There is also no evidence that vitamins and supplements have any beneficial effect on the condition, but regular physical activity and brain-challenging workouts were shown to help to some extent.

"On the positive side, there have been some signals of hope from exercise and cognitive training and rehabilitation, so things that keep the mind moving and the body moving."

Pottie said the recommendations apply to older seniors as well, so an 85-year-old not experiencing a noticeable decline in memory or reduced decision-making ability, for instance, should also not receive routine screening for mild cognitive impairment.

"We're talking about the general population without symptoms; we are not talking about people with symptoms," he stressed.

"So when people such as family members are concerned about somebody or when the patient is concerned themselves, then we want the doctor to do their job, which means a diagnostic inquiry, which may involve a screening tool, but will also consider other diseases."

The new guidelines were published Monday in the Canadian Medical Association Journal and are available online at http://www.canadiantaskforce.ca.