Aim The main purpose of the present study was to verify the feasibility of wearable inertial sensors (IMUs) in a clinical setting to screen gait and functional mobility in Italian older persons. In particular, we intended to verify the capability of IMUs to discriminate individuals with and without cognitive impairments and assess the existence of significant correlations between mobility parameters extracted by processing trunk accelerations and cognitive status. Methods This is a cross-sectional study performed on 213 adults aged over 65 years (mean age 77.0 ± 5.4; 62% female) who underwent cognitive assessment (through Addenbrooke’s Cognitive Examination Revised, ACE-R) instrumental gait analysis and the Timed Up and Go (TUG) test carried out using a wearable IMU located in the lower back. Results Individuals with cognitive impairments exhibit a peculiar gait pattern, characterized by significant reduction of speed (− 34% vs. healthy individuals), stride length (− 28%), cadence (− 9%), and increase in double support duration (+ 11%). Slight, but significant changes in stance and swing phase duration were also detected. Poorer performances in presence of cognitive impairment were observed in terms of functional mobility as overall and sub-phase TUG times resulted significantly higher with respect to healthy individuals (overall time, + 38%, sub-phases times ranging from + 22 to + 34%), although with some difference associated with age. The severity of mobility alterations was found moderately to strongly correlated with the ACE-R score (Spearman’s rho = 0.58 vs. gait speed, 0.54 vs. stride length, 0.66 vs. overall TUG time). Conclusion The findings obtained in the present study suggest that wearable IMUs appear to be an effective solution for the clinical assessment of mobility parameters of older persons screened for cognitive impairments within a clinical setting. They may represent a useful tool for the clinician in verifying the effectiveness of interventions to alleviate the impact of mobility limitations on daily life in cognitively impaired individuals.

The main purpose of the present study was to compare the smoothness of gait in older adults with and without cognitive impairments, using the harmonic ratio (HR), a metric derived from trunk accelerations. Ninety older adults aged over 65 (age: 78.9 ± 4.8 years; 62% female) underwent instrumental gait analysis, performed using a wearable inertial sensor and cognitive assessment with the Mini Mental State Examination (MMSE) and Addenbrooke’s Cognitive Examination Revised (ACE-R). They were stratified into three groups based on their MMSE performance: healthy controls (HC), early and advanced cognitive decline (ECD, ACD). The spatio-temporal and smoothness of gait parameters, the latter expressed through HR in anteroposterior (AP), vertical (V) and mediolateral (ML) directions, were derived from trunk acceleration data. The existence of a relationship between gait parameters and degree of cognitive impairment was also explored. The results show that individuals with ECD and ACD exhibited significantly slower speed and shorter stride length, as well as reduced values of HR in the AP and V directions compared to HC, while no significant differences were found between ECD and ACD in any of the investigated parameters. Gait speed, stride length and HR in all directions were found to be moderately correlated with both MMSE and ACE-R scores. Such findings suggest that, in addition to the known changes in gait speed and stride length, important reductions in smoothness of gait are likely to occur in older adults, owing to early/prodromal stages of cognitive impairment. Given the peculiar nature of these metrics, which refers to overall body stability during gait, the calculation of HR may result in being useful in improving the characterization of gait patterns in older adults with cognitive impairments.

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Background. The Motoric Cognitive Risk (MCR) syndrome is defined in non-demented older adults by cognitive complaints and slow gait. Individuals with MCR are at higher risk of dementia and other poor clinical outcomes, such as falls. However, no data are available as regards functional mobility alterations associated with MCR. The main purpose of the present study is to quantitatively investigate such an aspect using the instrumented Timed-Up-and-Go (iTUG) test carried out using a wearable inertial measurement unit (IMU). Methods. Fifty-one women aged over 65 years underwent a geriatric and neuropsychologic assessment (which included the Mini Mental State Examination, MMSE and Addenbrooke's Cognitive Examination Revised, ACE-R), instrumented gait analysis and iTUG performed using an IMU located on the lower back. Based on subjective cognitive complaints and slow gait, they were assigned either to the MCR (n = 24) or non-MCR (n = 27) group. IMU data allowed calculation of overall and sub-phases iTUG times. Results. Women with MCR were characterized by a significantly higher body mass and body mass index, lower normalized handgrip strength, and similar values of MMSE compared to non-MCRs. A trend was observed in terms of lower overall and sub-domain ACE-R score. They also performed iTUG at a significantly slower speed (22.4 s vs 14.1 of the non-MCR group, p < 0.001) and exhibited increased sub-phase times (29 to 31% higher with respect to non-MCRs). Conclusions. The findings of the present study suggest that the MCR syndrome impairs functional mobility, probably due reduced muscular strength and coordination, fear of falling and increased instability. The instrumental evaluation of functional mobility appears useful in the management of women with MCR, particularly in monitoring the progression of the motor impairments, verifying the effectiveness of interventions targeted in alleviating the impact on daily life of mobility limitations associated with MCR and in defining tailored rehabilitation programs.

The contribution of motor efficiency to the maintenance of psychological well-being in cognitively impaired older individuals is still insufficiently examined. This investigation primarily intended to evaluate whether muscular strength mediates the relationship between different facets of psychological well-being (i.e., personal satisfaction, emotional competence, coping), negative mood, and central executive efficiency through the Clock-Drawing, Trail-Making (Part A), and verbal fluency tests. Furthermore, the impact of cognitive decline on self-reported psychological well-being and depression was explored, using the handgrip strength (HGS) measure as a covariate. One hundred and nineteen older participants, 44 males and 75 females, aged 63 years and older (Mage = 77.7 years, SD = 5.6 years), completed a battery of tests assessing executive functions, HGS, depression, and psychological well-being. Significant low to moderate associations were found between distinct executive functions, HGS, psychological well-being, and depression. In addition, personal satisfaction did not correlate with any measure of executive functions, the clock-drawing score was associated only with coping index, and self-reported depression correlated only with the Trail-Making Test score. Moreover, a series of mediation analyses documented that executive functions (primarily assessing verbal fluency and motor speed) and HGS explained approximately 20–46% of the variance in perceived psychological well-being and depression. Finally, more cognitively impaired participants reported worse total psychological well-being, emotional competence, and coping. In conclusion, motor proficiency mediates the relationship between selective measures of executive functions and perceived psychological well-being and depression in cognitively impaired individuals.