THE NEUROLOGIC SYNDROME OF SEVERE ALZHEIMERS-DISEASE - RELATIONSHIP TO FUNCTIONAL DECLINE

Objective.-To assess the possible association between functional decli ne and noncognitive neurologic signs in the severe stages of Alzheimer 's disease (AD).Design.-Case series. Setting.-Subjects from a dementia research referral center, longitudinally followed, when necessary, in to residential home and nursing home settings. Patients.-A consecutive sample of 56 patients (16 men, 40 women; mean age, 74.6 years) with a clinical diagnosis of probable AD in the moderately severe and severe stages. Main Outcome Measure.-For global dementia severity, the Globa l Deterioration Scale and Mini-Mental State examination; for functiona l assessment, the Functional Assessment Staging Scale; and for assessm ent of neurologic function, nine release signs (primitive reflexes), 1 0 measures of extrapyramidal function, and five measures of pyramidal function, including deep-tendon reflexes and plantar signs. Changes in activity or presence of neurologic signs were rated on a seven-point scale. Results were analyzed in terms of prevalence and magnitude of c hange in relation to functional impairment. Results.-Prevalence and me an scores of certain release signs, certain extrapyramidal measures co mmonly referred to as bradykinesia, and certain pyramidal signs showed significant associations with the magnitude of functional impairment. Other neurologic measures, for example, the palmomental reflex, and c ertain extrapyramidal measures commonly seen in Parkinson's disease, i ncluding the glabellar blink reflex, cogwheeling, tremor, shuffling ga it, and festination, did not show significant increments with continui ng functional decline in AD. Conclusions.-Functional decline in the ad vanced stages of AD appears to be associated with a particular combina tion of progressive cortical, extrapyramidal, and pyramidal system dys function. The characteristics of this neurologic syndrome of the sever e stages of AD differ from those of other neurologic disorders. For ex ample, the pattern of extrapyramidal system disease is different from that seen in Parkinson's disease. The neurologic syndrome of the sever e stages of AD is amenable to description and deserves further investi gation.