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FROM: Wall Street Journal New Test May Detect Parkinson's Early, Aid Search for Drugs by Scott Hensley. Wall Street Journal (Eastern Edition). Jan 7, 2005. p. B.1 "WHEN PARKINSON'S disease progresses far enough, the symptoms are as heartbreaking as they are unmistakable: trembling in the limbs, difficulty controlling movement, and even, eventually, paralysis. But in the early stages of the disease, telltale signs are tricky to spot. One doctor seeing a patient with infrequent blinking or a slight tremor will diagnose Parkinson's, while another might dismiss those symptoms as nothing to worry about. By the time unambiguous symptoms emerge, Parkinson's has usually been on the attack for years, destroying 60% or more of the special cells in the brain that control voluntary movement. Now scientists at drug giant Pfizer think they have stumbled on a simple test that is both sensitive enough to detect subtle biological changes due to Parkinson's and specific enough to avoid false alarms: analyzing how people speak. If further studies confirm their conclusion, the test could offer a more accurate way to diagnose Parkinson's before large numbers of brain cells are irreversibly lost, and speed the development of new drugs for the disease. With many illnesses, particularly those of the nervous system, doctors make a diagnosis by eliminating alternatives. Even with advances in brain scans, they rely primarily on questionnaires, physical exams and intuition to identify common disorders, such as Alzheimer's, as well as rarer ones, including Parkinson's. THE PFIZER RESEARCHERS wondered if they could do better. Rather than draw blood or even spinal fluid, they believed it might be possible to detect the illness by analyzing speech patterns. In Parkinson's, the characteristic decline in muscle control stems from the loss of dopamine-producing nerve cells in the substantia nigra, a compact region in the middle of the brain. Building on insights from other scientists, Pfizer researchers reasoned that hesitation and hitches later seen in the movement of large muscles might be apparent earlier in shaking or trembling of the tiny muscles involved in speech, including the vocal cords. In 2001, Pfizer neuroscientist Peter Snyder and colleagues began working with a computer system to analyze the variability of speaking tone and the length of pauses between consonants and vowels. To test their techniques, the researchers searched news databases for public figures diagnosed with Parkinson's, a group that includes actor Michael J. Fox, former Attorney General Janet Reno and boxer Muhammad Ali. They focused on two people whose dates of diagnosis were a matter of public record and for whom there were plenty of voice recordings made years before as well as after the illness was identified. The subjects, aged 42 and 65 in 2003, haven't been named publicly because of rules about patient privacy. Two other people matched by age and profession but with no known history of neurological problems served as comparison subjects. Using a commercial voice-analysis computer program, the Pfizer scientists evaluated interviews in CNN's video archives. They found the Parkinson's patients spoke in slight monotones years before they were diagnosed, though the changes were so slight they weren't detectable by the human ear. A subsequent test confirmed the findings in four patients recently diagnosed with Parkinson's. The results appeared in the Journal of Neurolinguistics in November. THE PARKINSON'S VOICE test takes about seven minutes and requires equipment costing only a few thousand dollars. For the moment, the scarcity of treatment options for patients with mild Parkinson's limit the usefulness of an early warning about the condition. "If you can't do anything about it, why tell people they have the disease?" says Howard Hurtig, a neurologist at Pennsylvania Hospital in Philadelphia. Nevertheless, research into reliable diagnostic markers of Parkinson's disease is drawing increased funding from the National Institutes of Health. The Michael J. Fox Foundation launched a $2 million program in November to search for biological markers. "It's probably early to say that this acoustic approach would work," says Brian Fiske, a scientific manager for research programs at the foundation. But "there's a definite need for a good biomarker that would allow you to diagnose Parkinson's disease at an early stage," especially for drug development. Pfizer has no plans to market the speech test but may explore licensing the technology to other companies. Its ultimate goal is to find drugs that would change the course of Parkinson's and related diseases by protecting nerve cells. As things stand now, the lack of a standard test for Parkinson's, like blood sugar for diabetes, stymies efforts to gauge the effect of experimental drugs. "If symptoms are mild and you're treating early, then how do you know if your treatment is working?" asks Pfizer's Dr. Snyder. He acknowledges that his method must be validated in further tests before it can be used routinely. But in the meantime, his team has successfully applied the speech test to patients with depression and schizophrenia, which can also involve abnormal levels of dopamine in the brain." ---------------------------------------------------------------------- To sign-off Parkinsn send a message to: mailto:[log in to unmask] In the body of the message put: signoff parkinsn