http://www.boston.com/news/health/articles/2009/07/16/bu_study_finds_learning_alzheimers_risk_not_detrimental/
Learning Alzheimer's risk may do no harm BU finding belies old assumptions By Carolyn Y. Johnson, Globe Staff | July 16, 2009 If you found out you had an increased genetic risk for Alzheimer's disease, how would you feel? A new study to be published today suggests that you might not feel anxious or depressed - contrary to researchers' longstanding assumption that such news would be emotionally devastating. The study, led by researchers from Boston University School of Medicine, is one of the first to closely examine the psychological repercussions of learning about genetic risk for a deadly disease with no cure or prevention. It found that healthy people told they carry a gene that increases risk for Alzheimer's suffered no psychological harm during the year researchers spent following them. The research comes amid a growing scientific debate about the value of consumer genetic tests that identify elevated risk for dozens of diseases. "There was a virtual certainty among many, many people that you would do harm'' by revealing a person's genetic risk for Alzheimer's disease, said Dr. Robert Green, lead author of the study and a professor at BU School of Medicine. "What seems to happen is there are some people who benefit from knowing more information - information seekers, if you will - and they like to know as much as they can and they feel better, even if the information isn't always good news.'' For years, doctors have known that a gene called APOE e4 increases risk of Alzheimer's disease up to 15-fold, depending on whether a person carries one or two copies of the gene. But doctors have not recommended the test as a screening tool; there was no clear benefit, since there is no known prevention or cure for Alzheimer's, the thinking went. And harm seemed likely because the disease would frighten those at greater risk - or give false hope to some that they would not get the disease. That's because the gene's presence is not a guarantee that people will develop the disease, and its absence is not a reprieve. About 40 percent of people with Alzheimer's do not carry the gene at all, according to Dr. John B. Murphy, chairman of the board of the American Geriatrics Society, which has drafted a position statement describing the pitfalls of such testing. In addition to psychological effects, testing could also unveil a host of other troubling scenarios about insurance and privacy, despite legal protections. In order to test the psychological effects of risk awareness, Green and colleagues carefully screened people who had a parent with Alzheimer's, and excluded people with signs of cognitive problems or depression. The 162 participants, on average in their early 50s, received a 90-minute education session, had their blood drawn, and were randomly split into two groups: Two-thirds received genetic results and the rest received risk information related to gender and age. The results, published in The New England Journal of Medicine, showed no significant difference in depression or anxiety between people who were told their results and those who were not. There was a slight, temporary increase in test-related distress for subjects who tested positive for the gene, but researchers found no psychological risks over the course of a year. Regardless of the news they got, 98 percent of the people who were told their genetic results said they would do it again - even if they found out they had the gene. "It's information I wanted to have because I had a mother who died of Alzheimer's,'' said Robert McKersie, 79, an emeritus professor at the MIT Sloan School of Management, who learned that he carried a copy of the gene and was told he had a 10 percent risk of developing the disease between now and age 85. "I don't think I have any false sense of security. It doesn't change how I'm planning my life, and I still could come down with some severe dementia as I come into my 80s,'' McKersie said. "That's the enigma of probability.'' Other people do change their lives. Previous studies found that people with the gene were nearly six times more likely to change their long-term care insurance than those who did not learn their status. People who tested positive were also more likely to change their behaviors - everything from medications to diet - even though there is no known way to prevent the disease. Outside researchers praised the study, but said it was unable to conclude how an ordinary person who decides to buy a genetic test online would react, since the study patients were screened and counseled. Also while the study did not show harm, researchers do not yet suggest people should seek such testing. "People have been concerned there can be deleterious effects of this type of disclosure - and as we enter this personalized medicine age, genetic discoveries are becoming a dime a dozen,'' said Dr. Richard Caselli, a neurologist at the Mayo Clinic in Arizona. He tests people for the gene in studies intended to better understand the disease, but does not disclose the results to them. "It's fine to say most people will handle it well, but when you're dealing with large numbers of people you only need one person to jump out of a window to suddenly change everything,'' he said. The study did show that two of the three participants who received the most dire news - told they had two copies of the gene - had adverse psychological effects. Study researchers, however, determined the effect was caused by personal experiences unrelated to the test results. George Church, a Harvard Medical School geneticist who heads a project to sequence the genomes of 100,000 people, called the new research "kind of a reality check with respect to whether people are interested in this sort of data, and whether they're going to be overreacting to it.'' Tanya Zucconi, 44, who works as a senior analyst at Brigham and Women's Hospital, found out she has the gene, giving her a high risk of developing the disease over her lifetime. Evaluating risk is complicated and depends on a host of factors including gender and age, in addition to genetics. "I'd love it to be something lower, but that was useful information,'' Zucconi said. It is far from a certainty that she will get the disease, but Zucconi discussed it with her family - not wanting them to be caught off guard the way she was when her mother was diagnosed with probable Alzheimer's four years ago. "While I'm not sitting around waiting for it, and I certainly hope I'm wrong about it . . . my adult children are likely the ones who will have to deal with me if I go this route,'' Zucconi said. "We won't be so surprised.'' Carolyn Y. Johnson can be reached at [email protected]. [Non-text portions of this message have been removed]
