Medical professionals are much less likely to tell their patients of a diagnosis of Alzheimer's disease than diagnoses of other chronic or incurable diseases such as cancer, often because of a reluctance to inflict emotional distress, a nonprofit's annual report has found.The Alzheimer's Association, in its annual look at trends, financial costs and research into the dementia-causing illness, said Tuesday that less than half the people who have Alzheimer's reported being told they had the dementia-causing disease.This was not because the disease, which destroys people's memories and abilities to learn, had caused them to forget. The report's analytical methodology, comparing Medicare records with surveys of both beneficiaries and caregivers, found that doctors and other health care providers give people their diagnosis only about 45 percent of the time. By contrast, the disclosure rate is 93 percent for diagnoses of cancers that affect the breast, colon, rectum, lung or prostate.A common reason for failure to disclose a diagnosis of Alzheimer's was the perceived "stigma" of the disease and the reluctance to create additional emotional stress in a patient with a disease that is progressive, incurable and ultimately fatal, the report says."I think part of it has to do with, back in the day, if someone was given the diagnosis of Alzheimer's disease, it was the social kiss of death, because the impression was, there was nothing to do," said Pierre Tariot, geriatric psychiatrist and director of Banner Alzheimer's Institute in Phoenix. "And people are terribly afraid of a disease that robs you of your identity. They tend to look away."There is a virtual consensus in the profession that a patient is entitled to know.There are several negative consequences to not telling a person that he or she has Alzheimer's disease, the report says. Families are less able to make financial plans. They have less time to set up a team of caregivers. And it robs the person of his or her dignity and autonomy, the report says.The report says an estimated 5.3 million people are living with Alzheimer's disease, up from 5.2 million in the estimate from last year's annual report.