title: Terminal decline in motor function.
abstract: The study aim was to test the hypothesis that motor function undergoes accelerated decline proximate to death. As part of a longitudinal clinical-pathologic study, 124 older Roman Catholic nuns, priests, and monks completed at least 7 annual clinical evaluations, died, and underwent brain autopsy and uniform neuropathologic examination. Each evaluation included administration of 11 motor tests and 19 cognitive tests from which global measures of motor and cognitive function were derived. The global motor measure (baseline M = 0.82, SD = 0.21) declined a mean 0.024 unit per year (95% confidence interval [CI]: -0.032, -0.016) until a mean of 2.46 years (95% CI: -2.870, -2.108) before death when rate of decline increased nearly fivefold to -0.117 unit per year (95% CI: -0.140, -0.097). The global cognitive measure (baseline M = 0.07, SD = 0.45) declined a mean of 0.027-unit per year (95% CI: -0.041, -0.014) until a mean of 2.76 years (95% CI: -3.157, -2.372) before death when rate of decline increased more than 13-fold to -0.371 unit per year (95% CI: -0.443, -0.306). Onset of terminal motor decline was highly correlated with onset of terminal cognitive decline (r = .94, 95% CI: 0.81, 0.99), but rates of motor and cognitive change were not strongly correlated (preterminal r = .20, 95% CI: -0.05, 0.38; terminal r = .34, 95% CI: 0.03, 0.62). Higher level of plaques and tangles was associated with earlier onset of terminal decline in motor function, but no pathologic measures were associated with rate of preterminal or terminal motor decline. The results demonstrate that motor and cognitive functions both undergo a period of accelerated decline in the last few years of life.
authors.affiliation: Rush Alzheimer's Disease Center, Chicago, IL 60612, USA. rwilson@rush.edu
authors.forename: Robert S
authors.initials: RS
authors.lastname: Wilson
authors.forename: Eisuke
authors.initials: E
authors.lastname: Segawa
authors.forename: Aron S
authors.initials: AS
authors.lastname: Buchman
authors.forename: Patricia A
authors.initials: PA
authors.lastname: Boyle
authors.forename: Loren P
authors.initials: LP
authors.lastname: Hizel
authors.forename: David A
authors.initials: DA
authors.lastname: Bennett
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000473:pathology / Q000502:physiology*; D001921:Brain / Q000473:pathology; D003071:Cognition; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D009048:Motor Skills / Q000502:physiology*; D009483:Neuropsychological Tests