Doctors often hesitate to tell patients they likely suffer from Alzheimer's disease or another form of dementia, fearing the news will overwhelm them. But a study by Washington University in St. Louis suggests physicians need not worry.

Not only did the diagnosis not increase anxiety or depression among patients and their caregivers, but most were relieved to have symptoms explained and a way to find help.

"It's not good news. No one is pleased to find out they have dementia," said Brian Carpenter, co-investigator and associate professor of psychology at Washington University. "But some people find comfort in getting resolution to their anxiety and concerns, and knowing that people can help them."

The study, which appears in the March issue of the Journal of the American Geriatrics Society, gauged depression and anxiety two days before and two days after an evaluation and diagnosis.

Medical practice guidelines say doctors should tell their patients about a dementia diagnosis regardless of the stage of the disease.

But a review of published studies dating from the 1970s until very recently showed half of doctors were not telling their patients what they suspected, the researchers said.

Scott Roberts, an Alzheimer's researcher at the University of Michigan who was not involved in the study, said medical ethicists debate patients' right to information and the fear that such knowledge may upset them.

"This study is interesting, because it shows a lot of the paternalistic fears are not supported by the data," he said.

Neurologist John Morris, who heads the Alzheimer's Disease Research Center at Washington University where the study subjects were evaluated, said doctors have varying comfort levels, in part because of uncertainty the diagnosis is accurate.

He said he wanted to evaluate patients' reactions because early detection has advantages, such as enabling patients to plan for their future care.

In the St. Louis study, 90 patients and their caregivers were interviewed at the center two days before the evaluation, and by telephone two days later. Their levels of anxiety and depression were gauged based on answers to standardized questionnaires.

On average, for both patient and caregiver, anxiety and depression levels were the same or had decreased.

The researchers acknowledged that their study has limitations, and they plan additional research to expand their inquiry.

The study gauged the subjects' emotional state at only two points in time. A future study will gauge their reactions over a year.

And the very setting for the study — an Alzheimer's research center — may have influenced patients' and caregivers' expectations, researchers said.

Study subjects likely received more information and support at the center than the average patient does in a primary care doctor's office. Future studies will look at primary care and neurology and geriatrics clinics.

"It's a significant study for as far as it goes," said Dr. Greg Sachs, a research scientist at Indiana University's Center for Aging Research.

How the diagnosis is delivered, and what kind of support is offered, may have a lot to do with reaction, he said.

Sachs cautioned that study results should not be used to argue for wider screening of dementia at health fairs and doctors' offices. Available treatments are expensive and only modestly helpful, he added, and many doctors are ill-equipped to meet the challenges posed by such patients and their families.

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