Cognitive Enhancers as a Means to Reduce Falls in Older Adults
The etiology of falls is multifactorial and hence a single treatment intervention is unlikely to be effective for falling. Cognitive enhancer pharmacotherapy may be of potential benefit to reduce fall risk in older adults with evidence of cognitive impairment. Data from subjects with Parkinson disease (PD) indicate significant reductions in falls with cholinergic augmentation therapy, especially in those with more frequent falls. Preliminary data from cholinesterase inhibitor treatment in patients with mild cognitive impairment (MCI) and Alzheimer disease (AD) suggest that these drugs may improve gait indices that typically reflect higher fall risk. Data from noradrenergic drug clinical trials and gait are less consistent but suggest improved gait functions but only in advanced post-surgical PD subjects. Fall-reducing effects of droxidopa in PD are likely related to the drug’s blood pressure increasing rather than cognitive enhancer effects. Given the accumulating evidence of increased fall risk due to anticholinergic medication burden in non-PD elderly, reduction and preferably elimination of such medications should be a first management step in this population. There is a clear need for cognitive enhancer clinical trials in targeted non-PD elderly at risk of falling. Although fall frequency may be the gold outcome variable for such studies, surrogate measures that reflect increased fall risk may be needed if fall frequency is less than a weekly or monthly occurrence.
KeywordsAcetylcholine Alzheimer disease Brain network Cognition Falls Dementia with Lewy bodies Parkinson disease
mild cognitive impairment
Parkinson disease with dementia
The presented research data from the authors’ work was supported by grants from the NIH [P01 NS015655, RO1 NS070856, with additional support from P50 NS091856], Department of Veterans Affairs [I01 RX000317] and the Michael J. Fox Foundation.
All reported studies/experiments with human subjects performed by the authors have been previously published and complied with all applicable ethical standards (including the Helsinki declaration and its amendments, institutional/national research committee standards, and international/national/institutional guidelines).
No potential conflicts of interest relevant to this chapter were reported.
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