Mobility and associations with levels of cerebrospinal fluid amyloid ß and tau in a memory clinic cohort.

Background: Mobility impairments, in terms of gait and balance, are common in persons with dementia. To explore this relationship further, we examined the associations between mobility and cerebrospinal fluid (CSF) core biomarkers for Alzheimer's disease (AD). Methods: In this cross-sectional study, we included 64 participants [two with subjective cognitive decline (SCD), 13 with mild cognitive impairment (MCI) and 49 with dementia] from a memory clinic. Mobility was examined using gait speed, Mini-Balance Evaluation Systems test (Mini-BESTest), Timed Up and Go (TUG), and TUG dual-task cost (TUG DTC). The CSF biomarkers included were amyloid-ß 42 (Aß42), total-tau (t-tau), and phospho tau (p-tau181). Associations between mobility and biomarkers were analyzed through correlations and multiple linear regression analyses adjusted for (1) age, sex, and comorbidity, and (2) SCD/MCI vs. dementia. Results: Aß42 was significantly correlated with each of the mobility outcomes. In the adjusted multiple regression analyses, Aß42 was significantly associated with Mini-BESTest and TUG in the fully adjusted model and with TUG DTC in step 1 of the adjusted model (adjusting for age, sex, and comorbidity). T-tau was only associated with TUG DTC in step 1 of the adjusted model. P-tau181 was not associated with any of the mobility outcomes in any of the analyses. Conclusion: Better performance on mobility outcomes were associated with higher levels of CSF Aß42. The association was strongest between Aß42 and Mini-BESTest, suggesting that dynamic balance might be closely related with AD-specific pathology.

Exploring life-space in the nursing home. An observational longitudinal study.

BACKGROUND: Traditional performance-based measurements of mobility fail to recognize the interaction between the individual and their environment. Life-space (LS) forms a central element in the broader context of mobility and has received growing attention in gerontology. Still, knowledge on LS in the nursing home (NH) remains sparse. The aim of this study was to identify LS trajectories in people with dementia from time of NH admission, and explore characteristics associated with LS over time. METHODS: In total, 583 people with dementia were included at NH admission and assessed biannually for 3 years. LS was assessed using the Nursing Home Life-Space Diameter. Association with individual (age, sex, general medical health, number of medications, pain, physical performance, dementia severity, and neuropsychiatric symptoms) and environmental (staff-to-resident ratio, unit size, and quality of the physical environment) characterises was assessed. We used a growth mixture model to identify LS trajectories and linear mixed model was used to explore characteristics associated with LS over time. RESULTS: We identified four groups of residents with distinct LS trajectories, labelled Group 1 (n = 19, 3.5%), Group 2 (n = 390, 72.1%), Group 3 (n = 56, 10.4%), Group 4 (n = 76, 14.0%). Being younger, having good compared to poor general medical health, less severe dementia, more agitation, less apathy, better physical performance and living in a smaller unit were associated with a wider LS throughout the study period. CONCLUSION: From NH admission most NH residents' LS trajectory remained stable (Group 2), and their daily lives unfolded within their unit. Better physical performance and less apathy emerged as potentially modifiable characteristics associated with wider LS over time. Future studies are encouraged to determine whether LS trajectories in NH residents are modifiable, and we suggest that future research further explore the impact of environmental characteristics.

Physical performance across the cognitive spectrum and between dementia subtypes in a population-based sample of older adults: The HUNT study.

BACKGROUND: Literature on physical performance in older adults across the cognitive spectrum remains inconclusive, and knowledge on differences between dementia subtypes is lacking. We aim to identify distinct physical-performance deficits across the cognitive spectrum and between dementia subtypes. METHODS: 11,466 persons were included from the 70-year-and-older cohort in the fourth wave of the Trøndelag Health Study (HUNT4 70+). Physical performance was assessed with the Short Physical Performance Battery (SPPB), 4-meter gait speed, five-times-sit-to-stand (FTSS), grip strength and one-leg-standing (OLS). Clinical experts diagnosed dementia per DSM-5 criteria. Multiple linear and logistic regression were performed to analyze differences between groups. Age, sex, education, somatic comorbidity, physical activity and smoking status were used as covariates. RESULTS: Gait speed declined across the cognitive spectrum, beginning in people with subjective cognitive decline (SCD). Participants with mild cognitive impairment (MCI) additionally showed reduced lower-limb muscle strength, balance and grip strength. Those with dementia scored lowest on all physical-performance measures. Participants with Alzheimer's disease (AD) had a higher SPPB sum score and faster gait speed than participants with vascular dementia (VaD) and Lewy body dementia (LBD); participants with VaD and LBD had lower odds of being able to perform FTSS and OLS than participants with AD. CONCLUSIONS: Physical performance declined across the spectrum from cognitively healthy to SCD to MCI and to dementia. Participants with AD performed better on all assessments except grip strength than participants with VaD and LBD. Stage of cognitive impairment and dementia subtype should guide exercise interventions to prevent mobility decline and dependency.

Quantifying physical activity in aged residential care facilities: A structured review.

BACKGROUND: Engaging aged residential care (ARC) residents with physical activity (PA) may be a useful strategy to decelerate dependence and disability. It is unclear what volume, intensity and patterns of PA ARC residents participate in. This review aims to synthesize the literature to quantify the volume, intensity and pattern of PA that ARC residents participate in across differing care levels (e.g. low, intermediate, high, mixed), and make recommendations for future research. METHODS: 30 studies of 48,760 yielded were reviewed using systematic review strategies. RESULTS: Questionnaires and technological tools were used to assess PA, with accelerometers employed in 70% of studies. Overall, studies reported low volumes and intensities of PA across all care levels, and suggested limited variation in patterns of PA (e.g. little day-to-day variation in total PA). There was limited inclusion of people with cognitive impairment, potentially causing representativeness bias. Findings were limited by lack of consistency in methodological approaches and PA outcomes. DISCUSSION: Based on findings and limitations of current research, we recommend that total volume or low-light intensity PA are more useful interventional outcomes than higher-intensity PA. Researchers also need to consider which methodology and PA outcomes are most useful to quantify PA in ARC residents.

Trajectories of physical performance in nursing home residents with dementia.

BACKGROUND: In nursing homes (NH) the prevalence of dementia ranges from 50 to 84% and most residents have extensive physical-performance impairments. However, from time of admission, development of physical performance in NH residents with dementia remains unexplored. AIMS: To explore the overall trend in physical performance, associated characteristics, and groups following distinct trajectories from time of admission, in NH residents with dementia. METHODS: We followed newly admitted NH residents diagnosed with dementia (N = 583) from 47 NHs across Norway for 3 years. Individual assessments were conducted biannually, and main outcome measure was the Short Physical Performance Battery (SPPB). Facility-level characteristics included unit size, staff-to-resident ratio, and quality of the physical environment (Special Care Unit Environmental Quality Scale, SCUEQS). RESULTS: From time of admission, NH residents with dementia showed a significant overall decline in physical performance. Further, we identified three distinct trajectory groups with significantly different baseline physical-performance status ("good," "moderate," and "poor"), differences between groups maintained and all declined across time. Younger age, good general medical health, less-severe dementia, and less musculoskeletal pain were associated with both an average higher overall trend and better baseline group-belonging. Additionally, less apathy and more psychosis were associated with a higher overall trend, and agitation was associated with poorer baseline group-belonging. CONCLUSIONS: To prevent excessive decline in physical performance in this population, NH clinicians should focus efforts specifically on assessment of physical performance at admission and on identification and management of musculoskeletal pain and neuropsychiatric symptoms.

Mobility and cognition at admission to the nursing home - a cross-sectional study.

BACKGROUND: Earlier studies show that the main reasons for admission to long-term nursing home care are cognitive impairment and functional impairments of activities of daily life. However, descriptive evidence of mobility is scant. The aims of this study were to describe mobility at admission to nursing homes and to assess the association between mobility and degree of dementia. METHODS: We included 696 residents at admission to 47 nursing homes in Norway. Inclusion criteria were expected stay for more than 4 weeks and 65 years or older. In addition, younger residents with dementia were included. Residents with life expectancy shorter than six weeks were excluded. Mobility was assessed using the Short Physical Performance Battery (SPPB) and the Nursing Home Life Space Diameter (NHLSD). The Clinical Dementia Rating Scale (CDR) was used to describe the degree of dementia. The associations between mobility and degree of dementia was analysed using the Chi-square and the Kruskal-Wallis test (KW-test). When the KW-test indicated a statistical significant difference, we proceeded with planned group comparisons with the Mann-Whitney U-test. In addition, we performed multiple linear regression analyses to control for potential confounders. RESULTS: Forty-three percent of the residents were not able to perform the balance test in SPPB. Twenty-four percent of the residents were not able to walk four meters, while only 17.6% had a walking speed of 0.83 m/s or higher. Sixty-two percent of the residents were not able to rise from a chair or spent more than 60 s doing it. The median score on NHLSD area was 22 (IQR 17) and the median score on NHLSD dependency was 36 (IQR 26). Residents with severe dementia had significantly lower levels of mobility than residents with moderate dementia. Cognitive function was associated with SPPB and NHLSD dependency in the adjusted models. CONCLUSION: Nursing home residents form a frail, but heterogeneous group both in terms of cognition and mobility at admission. Mobility was negatively associated with cognitive function, and residents with severe dementia had significantly lower levels of mobility than residents with moderate dementia.