The neurologic syndrome of severe Alzheimer's disease. Relationship to functional decline
E. H. Franssen, A. Kluger, C. L. Torossian and B. Reisberg
Aging and Dementia Research Center, New York University Medical Center, NY 10016.
OBJECTIVE--To assess the possible association between functional decline
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, into
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 Global Deterioration
Scale and Mini-Mental State examination; for functional assessment, the
Functional Assessment Staging Scale; and for assessment of neurologic
function, nine release signs (primitive reflexes), 10 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 change in relation to functional
impairment. RESULTS--Prevalence and mean scores of certain release signs,
certain extrapyramidal measures commonly 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 certain extrapyramidal measures commonly seen in
Parkinson's disease, including the glabellar blink reflex, cogwheeling,
tremor, shuffling gait, and festination, did not show significant
increments with continuing functional decline in AD.
CONCLUSIONS--Functional decline in the advanced stages of AD appears to be
associated with a particular combination of progressive cortical,
extrapyramidal, and pyramidal system dysfunction. The characteristics of
this neurologic syndrome of the severe stages of AD differ from those of
other neurologic disorders. For example, the pattern of extrapyramidal
system disease is different from that seen in Parkinson's disease. The
neurologic syndrome of the severe stages of AD is amenable to description
and deserves further investigation.
