Curious links have come to light in the past few years between two seemingly unrelated types of mental affliction. Persons with Down's syndrome tend to survive longer because of better care, and those few who live to age 35 or more nearly always develop a form of dementia that closely resembles the clinical picture of patients with a presumptive diagnosis of Alzheimer's disease. Their brains at autopsy show the typical neurofibrillary tangles and senile plaques.
Other links between these disorders also have been observed. For example, Albert Heyman, MD, professor of neurology, Duke University School of Medicine, Durham, NC, recently published results of a study involving 1,200 families of patients with Alzheimer's disease (Ann Neurol 1983;14:507-519). Heyman found that the immediate families of patients with Alzheimer's disease have an incidence of Down's syndrome three times greater than would be expected in the general population.
Such facts have led some investigators