Preclinical Disability

Accomplishing a compression of morbidity will require prevention of disability, a significant component of illness in older adults. To do this, better understanding is needed of the natural history of functional loss prior to disability. The authors hypothesize that there is an identifiable stage of preclinical disability that will predict future disability and identify a focus for prevention. It is proposed, based on observations in the Johns Hopkins Functional Status Laboratory, that preclinical disability is characterized by persons who perceive no difficulty with performance of a task and yet are found to have either (a) general diminution in activities requiring related abilities, or (b) changes in the performance of specific tasks. Both models are due to impairments. The authors suggest that nondisabled persons use compensatory strategies that minimize functional restrictions resulting from impairment; this may keep functional decline at a preclinical level. These hypotheses, if verified in prospective studies, may provide a basis for early detection of those at risk of disability and suggest effective preventive measures.