"The first new guidelines for diagnosing Alzheimers disease in nearly  years establish earlier stages of the mindrobbing disease paving the way for spotting and possibly treating these conditions much sooner than they are now. Grant Therkildsen The TimesPicayune archiveTobi and Ted Smith lead off the Alzheimer Associations second annual Northshore Memory Walk in May  in Covington. The first new guidelines in  years for diagnosing the disease establish earlier stages. The change reflects a modern view that Alzheimers is a spectrum of mental decline with damage that can start many years before symptoms appear. The new guidance describes three phases early brain changes mild cognitive impairment and fullblown Alzheimers. Yet the guidelines do not advise doctors to change how they evaluate and treat patients now. Despite the hoopla about new brain scans and blood and spinal fluid tests that claim to show early signs of Alzheimers they are not ready for prime time and should remain just tools for research the guidelines say. Its too soon right now to say these experimental biomarker tests will prove valid enough to be used in ordinary patient care said Creighton Phelps Alzheimers program chief at the National Institute on Aging. His institute and the Alzheimers Association convened several expert panels to write the guidelines the first since . They are being published Tuesday in Alzheimers  Dementia The Journal of the Alzheimers Association. About . million Americans and more than  million people worldwide have Alzheimers the most common form of dementia. Its likely there are at least as many people with mild cognitive impairment as with Alzheimers disease and maybe more said William Thies the Alzheimers Association scientific director. Even before this mild cognitive impairment shows up brain changes such as a buildup of sticky plaque or protein tangles inside nerves can suggest trouble ahead. Marilyn Albert a Johns Hopkins University researcher who led the mild cognitive impairment panel described this category as people who have mild progressive symptoms changes in mental abilities usually memory but not always memory that stop short of fullblown dementia. In doctors offices around the country people are coming in with much milder symptoms and many but not all will go on to develop Alzheimers she said. How can doctors tell whats going on First they try to determine how fast symptoms are progressing and do tests to rule out an obvious cause such as a stroke or a new medication. If symptoms are gradual and progressive doctors would likely diagnose mild cognitive impairment due to Alzheimers. But they wouldnt know for sure without additional tests like the experimental biomarker and imaging scans rapidly being developed and researched Albert said. One company has asked for government approval of a new type of brain scan it claims shows early signs of Alzheimers. Other companies are working on tests for substances in blood and spinal fluid. The guidelines say these are helpful for sorting people into clinical trials or monitoring the effects of experimental drugs but not for routine use in clinics and doctors offices. Dr. Clifford Jack a Mayo Clinic brain imaging specialist involved in the guidelines explained why. Unlike blood pressure tests that give fairly consistent readings regardless of what type of machine is used the new biomarker tests are not yet standardized from one lab or location to the next he said. There are no agreedupon cutoffs or levels for how much of a substance indicates impairment or Alzheimers. Theres not even enough research to validate that a particular substance or biomarker truly predicts progression of disease he said. A bigger problem is what to do after impairment or dementia has been diagnosed. Current treatments do not alter the course of Alzheimers they just ease symptoms. Many doctors believe drugs are being given too late after symptoms are severe so researchers more recently have started testing some in people with mild cognitive impairment. If youre only going to try them in people with advanced dementia the chance of them working is not going to be that great said Dr. Guy McKhann of Johns Hopkins University who headed one of the guideline panels. Early diagnosis is a first step and something the Alzheimers Association has long advocated Thies said. It allows people to anticipate whats going to happen in the future and plan their lives in ways to minimize the impact he said. People with the disease and their families cope better with their disease if they know what to expect. Marilynn Marchione AP Medical Writer Online National Institute on Aging http Alzheimers Association http"