.ntroduction The literature addressing the areas of mild cognitive impairment (MCI)1 and early Alzheimer’s disease (AD) is focused in part on the development of objective approaches to early diagnosis of cognitive change and memory loss and identification of predictors or correlates of these changes. Research has expanded our knowledge base about instruments
designed to identify changes in cognition and memory, but our ability to predict who will experience these changes remains limited. The emphasis on identifying risk factors in order to implement early interventions has increased as clinicians continue to identify medical therapies that delay the progression of neurodegenerative diseases such as AD.2
W. S. Maney & Son Ltd 2008 DOI 10.1179/174328808X252055 Physical Therapy Reviews 2008 VOL 13 NO 2 91
Research has begun to examine the relationship between changes in physical and cognitive functions in older adults with MCI and early stage AD. The importance of examining motor impairments within the older adult population is supported by previous studies that have found such impairments to be associated with earlier mortality,3–6 institutionalisa- tion,4,5,7 and increased cost of care in patients with dementia.8 This paper provides a descriptive review of research in the area of motor functioning in older adults with MCI and early AD. The specific aims of this paper are to examine: (1) the correlation between clinical measures of motor function and cognitive change in older adults; (2) clinical measures of motor function as predictors of conversion to cognitive impairment in healthy older adults and progression of cognitive impairment in people with MCI; (3) clinical measures of motor function as predictors of rate of decline in cognitive function in healthy older adults, people with MCI and those with early AD. An additional objective is to discuss the relevance of this information to the practice of physical therapy. There are several challenges inherent in a literature review of this nature. The terminology and definitions of constructs such as MCI, early AD and extrapyr- amidal symptoms (EPS) vary among studies and have evolved over time. There is also an intrinsic overlap between cognitive and physical functioning, thus proving it difficult to discuss one domain in isolation from the other. Finally, the types of motor function- ing that have been examined are various, from fine motor movement to gait impairments, thus creating a less homogeneous spectrum for this review. Constructs will be defined for the reader according to the studies in which they appear.