Objectives This study aims to establish reference data for nondemented adults between 80 and 84 years of age based on the German version of the Consortium to Establish a Registry for Alzheimer’s disease Neuropsychological (CERAD-NP) test battery and to assess the possible influence of hearing and vision impairments on CERAD-NP performance. Methods Two hundred one volunteers were examined with the German CERAD-NP test battery, and 18 test scores were calculated from the data. The sample included 99 men (49%), the mean age was 81.8 years ( SD = 1.3), and the mean years of education were 13.9 ( SD = 3.1). Percentiles for continuous and percentile ranks for discrete test scores were calculated separately for four norm groups. The groups were classified according to gender and education. Multiple regression analysis was used to predict cognitive performance from visual acuity and hearing ability. Results The normative data obtained were consistent with other findings from younger and older age groups. Worse visual acuity predicted slower performance in the Trail Making Test (TMT). None of the other CERAD-NP tests were correlated to sensory functions. Conclusions Using age-appropriate reference data, such as that established here for the 80–84 year age group can help to improve the detection of cognitive decline and prevent biases that arise when old-old adults are compared to younger old adults. Visual acuity should be considered an influencing factor on TMT performance.
Compared with healthy older adults, patients with Alzheimer’s disease show decreased alpha and beta power as well as increased delta and theta power during resting state electroencephalography (rsEEG). Findings for mild cognitive impairment (MCI), a stage of increased risk of conversion to dementia, are less conclusive. Cognitive status of 213 non-demented high-agers (mean age, 82.5 years) was classified according to a neuropsychological screening and a cognitive test battery. RsEEG was measured with eyes closed and open, and absolute power in delta, theta, alpha, and beta bands were calculated for nine regions. Results indicate no rsEEG power differences between healthy individuals and those withMCI. There were also no differences present between groups in EEG reactivity, the change in power from eyes closed to eyes open, or the topographical pattern of each frequency band. Overall, EEG reactivity was preserved in 80+-year-olds without dementia, and topographical patterns were described for each frequency band. The application of rsEEG power as a marker for the early detection of dementia might be less conclusive for high-agers.
Coordinated bimanual control depends on information processing in different intra-and interhemispheric networks that differ with respect to task symmetry and laterality of execution. Aging and age-related cognitive impairments, but also sex can have detrimental effects on connectivity of these networks. We therefore expected effects of age, cognitive function and sex on bimanual force coordination. We furthermore expected these effects to depend on the characteristics of the task (i.e., difficulty and symmetry). 162 right handed participants (19 younger adults [YA], 21-30 years, 9 females; 52 cognitively healthy older adults [HOA], 80-91 years, 32 females; and 91 older adults with mild cognitive impairments [MCI] 80-91 years, 37 females) performed isometric bimanual force control tasks that required following constant or alternating (cyclic sine-wave) targets and varied in symmetry, i.e., (i) constant symmetric, asymmetric [with constant left and alternating right (ii) or vice versa (iii)], (iv) alternating in-and (v) alternating antiphase (both hands alternating with 0 • or 180 • relative phase, respectively). We analyzed general performance (time on target), bimanual coordination as coupling between hands (linear correlation coefficient) and structure of variability (i.e., complexity measured through detrended fluctuation analysis). Performance and coupling strongly depended on task symmetry and executing hand, with better performance in symmetric tasks and in asymmetric tasks when the left hand produced a constant and the right hand an alternating force. HOA and MCI, compared to YA, showed poorer performance (time on target) and reduced coupling in in-and antiphase tasks. Furthermore, both groups of OA displayed less complex structure in alternating force production tasks, a marker of reduced control. In addition, we found strong sex effects with females displaying reduced coupling during in-and antiphase coordination and less complex variably structure in constant force production. Results of this study revealed strong effects of age, but also sex on bimanual force control. Effects depended strongly on task symmetry and executing hand, possibly due to different requirements in interhemispheric information processing. So far, we found no clear relationship between behavioral markers of bimanual force control and age-related cognitive decline (compared to healthy aging), making further investigation necessary.
Background: Dementia and cognitive decline are serious social and economic burdens. An increase in the population of older people, as well as longer lifespans mean that numbers of dementia cases are exponentially rising. Neuropathological changes associated with dementia are thought to appear before the clinical manifestation of cognitive symptoms, i.e., memory impairments. Further, some older adults (OA) experience cognitive decline before it can be objectively diagnosed. For optimal care of these patients, it is necessary to detect cognitive decline and dementia at an early stage. In this vein, motor, sensory, and neurophysiological declines could be promising factors if found to be present before the onset of cognitive impairment. Hence, the objective of the SENDA study is to develop a multi-dimensional sensor-based instrument that allows early detection of cognitive decline or dementia in OA with the help of cognitive, sensory, motor, and neurophysiological parameters before its clinical manifestation. Methods/design: In the cohort sequential study, participants are assigned to one of three study groups depending on their cognitive status: 1. cognitively healthy individuals (CHI), 2. subjectively cognitively impaired persons (SCI), or 3. (possible) mildly cognitively impaired persons (pMCI, MCI). All groups take part in the same cognitive (e.g., executive function tests), motor (e.g., gait analyses, balance tests), sensory (e.g., vibration perception threshold test, proprioception tests), and neurophysiological (e.g., electroencephalograms) measurements. Depending on the time at which participants are included into the study, all measurements are repeated up to four times in intervals of 8 months within 3 years to identify associations with cognitive changes over time. Discussion: This study aims to detect possible motor, sensory, neurophysiological, and cognitive predictors to develop an early screening tool for dementia and its pre-stages in OA. Thus, affected persons could receive optimal health care at an earlier time point to maintain their health resources. Trial status: The study is ongoing. The recruitment of participants will be continued until May 2020.
Frailty and gait under dual-task conditions in older adults with and without subjective or objective cognitive impairments K. Müller1, S. Fröhlich1, J. Rudisch1, C. Voelcker-Rehage1 1 Technische Universität Chemnitz, Sportpsychologie, Chemnitz, Germany Background. An early diagnosis of dementia and the pre-stages is necessary for optimal health care. As it is known that neuropathological changes appear before the clinical manifestation of cognitive symptoms, it is necessary to determine prodromal markers for early detection, e.g. motor parameters. The purpose of the study is to examine differences in frailty and gait between older adults (OA) with and without cognitive impairments. Methods. We assessed the subjective cognitive status using the ‘Fragebogen zur geistigen Leistungsfähigkeit’, and the objective cognitive status using the Montreal Cognitive Assessment in OA (M = 82.3 years, SD = 2.3). Data of 22 cognitive healthy OA (CHI), 21 OA with mild cognitive impairments (MCI), and 14 OA with subjective cognitive impairments (SCI) were analyzed. Frailty was measured with the Tilburg Frailty Indicator. Gait parameters (mean and coefficient of variation (CV) of gait speed and step length) were assessed using Optogait® over a walking distance of 12 meters. Following walking blocks were performed: preferred (A), fast walking (B), and dual-task walking (preferred walking while counting backwards by 1(C), 3(D), and 7(E); verbal fluency (F)). Results. OA with SCI or MCI showed significant higher values of frailty (F(2,54) = 7.21, p = .002, ηp2 = 0.21) than CHI. Significant differences between groups were found for CV of gait speed in conditions B and C with highest CV for MCI. CV of step length in conditions B, C and D differed significantly between groups with highest CV for MCI. There were no differences between the groups in the other gait parameters. Conclusion. Increased variability in gait parameters in OA with MCI could be a prodromal motor marker for early detection of dementia. To confirm these results, more OA will be included and the measurements will be repeated every eight months in the next two years. The project was funded by ESF and Sächsische AufbauBank-Förderbank (Project-Number: 100310502).
Background. Cognitive abilities, e.g., processing speed (PS), decline with increasing age, but are necessary for activities of daily life (ADL) and independent living, e.g., driving. Furthermore, PS is associated with an active lifestyle (Reppermund et al., 2011). Additionally, physical activity (Bott et al. 2017) of older adults and other leisure activities might play an important role in the maintenance of PS. In this study we investigated whether PS is related to physical performances in older adults. Methods. The Digit Symbol Substitution Test (DSST) was used to measure cognitive functions (PS, sustained attention) in 58 older adults between 80 and 92 years of age (25 male; age: M = 82.3, SD = 2.3). Cardiovascular fitness was measured by use of the 2 min step test and gait velocity using Optogait® over a walking distance of 12 meters in three different conditions: preferred walking, fast walking, dual-task walking (preferred walking while counting backwards by 7). A modified Florida Cognitive Activities Scale was used to collect data of leisure time activities (LTA; e.g., social activities). Multiple regression analysis also included age, global cognitive performance (Montreal Cognitive Assessment), education, sex, and comorbidities as possible predictors. Results. Multiple regression analysis (adjusted R² = .341, F(1,53) = 10.323, p = .000) indicated that LTA (β = .390 p = .001), preferred gait velocity (β = .266, p = .021), and global cognitive performance (β = .279, p = .016), but not cardiovascular fitness (β = 0.131, p = .374) predicted the PS performance. Conclusion. The results indicated that a lower amount of LTA and a lower gait velocity are predictors for cognitive decline in older adults. These results might be considered for the development of appropriate treatments to prevent age-related cognitive decline or cognitive disorders (e.g., dementia). The project was funded by ESF and Sächsische AufbauBank-Förderbank (Project-Number: 100310502).