Donepezil for gait and falls in mild cognitive impairment: a randomized controlled trial.

BACKGROUND AND PURPOSE: Cognitive enhancers are commonly prescribed to people with Alzheimer's disease and related dementias to improve cognition and function. However, their effectiveness for individuals in the pre-stages of dementia, particularly in functional motor outcomes, remains unknown. We aimed to determine the efficacy of donepezil, a cognitive enhancer that improves cholinergic neurotransmission, on gait performance in mild cognitive impairment (MCI). METHODS: This was a double-blind, placebo-controlled trial including 60 older adults with MCI, randomized to receive donepezil (10 mg/daily, maximal dose) or placebo. Primary outcome was gait speed (cm/s) under single and three dual-task conditions (counting backwards by 1 or 7 and naming animals) measured using an electronic walkway. Dual-task gait cost (DTC), a valid measure of motor-cognitive interaction, was calculated as the percentage change between single (S) and dual-task (D) gait speeds: [(S - D)/S] × 100. Secondary outcomes included attention, executive function, balance and falls. RESULTS: After 6 months, the donepezil group experienced an improvement in dual-task gait speed (range 4-11 cm/s), although this was not statistically significant. The donepezil group showed a significant reduction in DTC (improvement) by counting backwards by 1 and 7 compared with placebo (10.25% vs. 1.75%, P = 0.048; 21.38% vs. 14.64%, P = 0.037, intention-to-treat analysis). Per-protocol analyses showed that all three DTCs improved in the donepezil group, along with a non-significant reduction of rate of falls. CONCLUSIONS: Donepezil treatment improved dual-task gait speed and DTC in elderly patients with MCI. Our results support the concept of reducing falls in MCI by targeting the motor-cognitive interface.

The attentional demands of ambulating with an assistive device in older adults with Alzheimer's disease.

Ambulation with a mobility aid is a unique real-life situation of multi-tasking. These simultaneous motor tasks place increased demands on executive function in healthy young and older adults, but the demands have not been evaluated in people with Alzheimer's disease (AD). Mobility problems are common among adults with AD, leading to provision of a mobility aid to optimize independent activity. The study objectives were: (i) to determine the dual-task cost (DTC) associated with the use of a mobility aid in straight and complex path walking, and (ii) to evaluate the association between executive function and ambulation with a mobility aid in older adults with AD and age-sex matched cognitively normal controls. Fourteen people (mean age±SD, 72.6±9.9years) with a diagnosis of probable AD (MMSE range 12-25) and controls (mean age±SD, 72.9±9.5) walked at a self-selected pace and using a 4-wheeled walker in a 6m straight path and a Figure of 8 Test. Ambulation with the walker in a straight path produced a low DTC that was not different between the groups. Ambulation with the 4-wheeled walker in the complex path produced a significantly different DTC in the group with AD at -38.1±23.5% compared to -19.7±21.4% (p=0.041). Lower scores on executive function were associated with longer times across test conditions. Ambulation with a 4-wheeled walker, in particular maneuvering around obstacles, requires greater attentional costs in dementia. Future research should explore the timing for safely introducing mobility aids in AD and the role of improving executive function.

Defining Rehabilitation Success in Older Adults with Dementia--Results from an Inpatient Geriatric Rehabilitation Unit.

OBJECTIVE: To quantify the magnitude of functional recovery in older adults with and without dementia admitted to an inpatient geriatric rehabilitation program by measuring change in measures of global physical function and physical therapy treatment outcomes. DESIGN: Retrospective cohort study. SETTING: Rehabilitation academic hospital. PARTICIPANTS: Consecutive subjects, with (N=65, age 81.9±6.0 y) and without (N=157, age 82.8±7.2 y) a dementia diagnosis, had assessment data at admission and discharge from inpatient geriatric rehabilitation unit. INTERVENTIONS: Not applicable. MEASUREMENTS: The Functional Independence Measure (FIM) was used to estimate level of independence on activities of daily living. The Berg Balance Scale (BBS), Timed Up and Go Test (TUG) and 2 Minute Walk Test (2MWT) were used to estimate functional mobility and endurance. The FIM (total, motor subscale, cognitive subscale scores) were used to calculate rehabilitation efficacy and efficiency scores. RESULTS: After controlling for confounding, there was no group difference for gains on the BBS, TUG, 2MWT; there was no group difference on rehabilitation efficacy and efficiency values based on the FIM motor subscale. The magnitude of the rehabilitation gain using the total FIM score was statistically different between groups, people with dementia having smaller gains. CONCLUSION: Older adults with a diagnosis of dementia are capable of making motor function recovery during inpatient sub-acute rehabilitation comparable to their peers without a dementia diagnosis. The metric used to evaluate functional recovery influences the determination of rehabilitation success between groups. Rehabilitation success should be defined among people with a dementia diagnosis by a change in the motor subscale of the FIM, rather than the total FIM score or the gain relative to the maximal FIM score.

Dual-task testing to predict falls in community-dwelling older adults: a systematic review.

BACKGROUND: Cognitive impairment increases fall risk in older adults. Dual-task testing is an accepted way to assess the interaction between cognition and mobility; however, there is a lack of evidence-based recommendations for dual-task testing to evaluate fall risk in clinical practice. OBJECTIVES: To evaluate the association between dual-task testing protocols and future fall risk, and to identify the specific dual-task test protocols associated with elevated risk. DATA SOURCES: MEDLINE, Pubmed and EMBASE electronic databases were searched from January 1988 to September 2013. STUDY SELECTION: Two independent raters identified prospective cohort studies (duration of at least 1 year) of dual-task assessment in community-dwelling participants aged ≥60 years, with 'falls' as the primary outcome. STUDY APPRAISAL AND SYNTHESIS METHODS: Methodological quality was scored independently by two raters using a published checklist of criteria for evaluating threats to the validity of observational studies. RESULTS: Deterioration in gait during dual-task testing compared with single-task performance was associated with increased fall risk. Shortcomings within the literature significantly limit knowledge translation of dual-task gait protocols into clinical practice. LIMITATIONS: There is a paucity of prospective studies on the association of dual-task gait assessment with fall risk. CONCLUSION AND IMPLICATIONS OF KEY FINDINGS: Changes in gait under dual-task testing are associated with future fall risk, and this association is stronger than that for single-task conditions. Limitations in the available literature preclude development of detailed recommendations for dual-task gait testing procedures in clinical practice to identify and stratify fall risk in older adults.

Facilitating Frailty Identification: Comparison of Two Methods among Community-Dwelling Order Adults.

BACKGROUND: Frailty is characterized by increased vulnerability for adverse events such as falls, fractures, placement, and death. Several frailty models have been developed, including the widely accepted Frailty Phenotype. However, the Frailty Phenotype can be difficult to apply in clinical practice. Alternatively, the Clinical Frailty Scale has been proposed based on its simplicity. To date, the Clinical Frailty Scale has not been validated against the Frailty Phenotype. OBJECTIVE: We aimed to test the inter-rater reliability of the Clinical Frailty Scale and its agreement with the Frailty Phenotype in frailty identification. DESIGN: Cross-sectional study. SETTING: Retirement community in London, Ontario, Canada. PARTICIPANTS: One hundred and four community-dwelling older adults (age ≥75 years). MEASUREMENTS: Participants were first classified using the Frailty Phenotype criteria as not frail, pre-frail or frail. Subsequently, two clinicians blinded to the first assessment, determined frailty status using the Clinical Frailty Scale. Differences between assessments were resolved by consensus. Inter-rater reliability was assessed using kappa statistics. Spearman Rho correlation coefficients evaluated the concurrent validity of the Clinical Frailty Scale against Frailty Phenotype components. RESULTS: Analysis with kappa statistic showed substantial agreement between raters in applying the Clinical Frailty Scale to the sample (κw= 0.76, 95% CI 0.68, 0.84). The Clinical Frailty Scale scores also positively correlated with an increasing number of Frailty Phenotype components (ρ=0.69, p<0.01). CONCLUSION: The Clinical Frailty Scale is reliable and comparable to the Frailty Phenotype in identifying frailty in community-dwelling older adults with the advantage of being easy to administer in clinical settings. Reliable tools to identify frailty in community-dwelling older adults may help provide timely interventions to ameliorate risk of adverse events.