Neurological findings in Alzheimer's disease and normal aging.

To determine the potential value of abnormal neurological findings as markers of Alzheimer's disease (AD) and their relationship to the stage of AD, we compared standardized neurological examinations in 135 community-dwelling patients with AD and 91 nondemented elderly individuals. After correcting for differences in age and education between the two groups, we found that rigidity, stooped posture, graphesthesia, neglect of simultaneous tactile stimuli (face-hand test), and snout, grasp, and glabella reflexes were present significantly more often in patients with AD than in control subjects. These findings increased in prevalence in patients with AD according to the severity of dementia. However, in a multivariate logistic regression model only the grasp reflex, graphesthesia, and the face-hand test were statistically significantly associated with the degree of cognitive impairment. Although abnormal neurological findings occur regularly in AD, they are too infrequent early in the course of AD to serve as diagnostic markers. Prospective studies are needed to determine whether patients with the early onset of extrapyramidal or other findings form a distinct subgroup of AD.