Unfortunately, the belief that all persons with Down syndrome get Alzheimer's disease appears to guide the evaluation of some people with Down syndrome who are declining in function. The misdiagnosis of Alzheimer's disease tends to increase the misperception that all people with Down syndrome will develop Alzheimer's disease. The use of this cyclical logic leads to more diagnoses of Alzheimer's disease. We have heard repeated stories of persons with Down syndrome who were declining in function, given a brief evaluation, and then were given the diagnosis of Alzheimer's disease. The potentially reversible causes were not ruled out. Much of the decline in function that we have seen experienced by persons with Down syndrome is reversible, and the quality of the person's life can often be improved. Even if some of these people later develop Alzheimer's disease, they often receive benefit in the interim from treatment of reversible disease processes. The diagnosis of Alzheimer's disease is still a diagnosis of exclusion, and a thorough evaluation for potentially reversible causes is indicated.

A close working relationship with the families and caregivers of the adults with Down syndrome has provided insight into their needs and leads us to argue for a multidisciplinary approach to diagnosis and care management. We have found that such a multidisciplinary approach can be instrumental in providing for the diagnosis of adults with Down syndrome who present with a decline in function. In our sample, there were a variety of medical and psychosocial problems causing the decline, and the team approach helped provide insight into these problems. Both a thorough medical and psychosocial are important to avoid missing reversible causes and over diagnosing Alzheimer's disease. Further evaluation of this and other approaches will aid in developing improved services to adults with Down syndrome.