Prevalence and treatment of atrial fibrillation in older adults.

BACKGROUND: Atrial fibrillation (AF) is the most frequent cardiac arrhythmia with an impact on morbidity and mortality found in the geriatric population. OBJECTIVE: This retrospective study is the first to investigate the prevalence, treatment and comorbidities of AF in a large cohort of older adults. MATERIAL AND METHODS: Older adults with AF hospitalized between 2010 and 2018. The mean age of the 10,700 AF patients in 2018 was 83.2 ± 6.4 years. The frequency of anticoagulation in older adults with AF between 2010 and 2018 was analyzed. The relationship between comorbidities and anticoagulation in 2018 was examined. Logistic regression analysis was used to identify possible predictive factors for anticoagulation. RESULTS: The prevalence of AF in 35,887 hospitalized older adults was 29.8% in 2018. The mean CHA2DS2VASc score was 4.4 ± 1.3 (male 3.8 ± 1.3, female 4.7 ± 1.2). From 2010 to 2018, the frequency of anticoagulation for patients with AF rose from 32.1% to 64.2%. Statistically significant differences in the examined characteristics between anticoagulated and not anticoagulated patients were found. Furthermore, there were no predictive factors for anticoagulation in multivariate logistic analysis. CONCLUSION: Hospitalized older adults have an increased prevalence of AF compared to the general population. Despite the higher risk of bleeding, older adults were more frequently anticoagulated in the observation period, preferably with direct oral anticoagulants (DOACs). Patients without anticoagulation had more diagnoses and were worse in functional tests. This study suggests that the decision to give anticoagulants to older adults should be personalized.

Exoscore: A Design Tool to Evaluate Factors Associated With Technology Acceptance of Soft Lower Limb Exosuits by Older Adults.

OBJECTIVE: This pilot study proposed and performs initial testing with Exoscore, a design evaluation tool to assess factors related to acceptance of exoskeleton by older adults, during the technology development and testing phases. BACKGROUND: As longevity increases and our aging population continues to grow, assistive technologies such as exosuits and exoskeletons can provide enhanced quality of life and independence. Exoscore is a design and prototype stage evaluation method to assess factors related to perceptions of the technology, the aim being to optimize technology acceptance. METHOD: In this pilot study, we applied the three-phase Exoscore tool during testing with 11 older adults. The aims were to explore the feasibility and face validity of applying the design evaluation tool during user testing of a prototype soft lower limb exoskeleton. RESULTS: The Exoscore method is presented as part of an iterative design evaluation process. The method was applied during an exoskeleton research and development project. The data revealed the aspects of the concept design that rated favorably with the users and the aspects of the design that required more attention to improve their potential acceptance when deployed as finished products. CONCLUSION: Exoscore was effectively applied to three phases of evaluation during a testing session of a soft exoskeleton. Future exoskeleton development can benefit from the application of this design evaluation tool. APPLICATION: This study reveals how the introduction of Exoscore to exoskeleton development will be advantageous when assessing technology acceptance of exoskeletons by older adults.

Instrumented gait analysis: a measure of gait improvement by a wheeled walker in hospitalized geriatric patients.

BACKGROUND: In an increasing aging society, reduced mobility is one of the most important factors limiting activities of daily living and overall quality of life. The ability to walk independently contributes to the mobility, but is increasingly restricted by numerous diseases that impair gait and balance. The aim of this cross-sectional observation study was to examine whether spatio-temporal gait parameters derived from mobile instrumented gait analysis can be used to measure the gait stabilizing effects of a wheeled walker (WW) and whether these gait parameters may serve as surrogate marker in hospitalized patients with multifactorial gait and balance impairment. METHODS: One hundred six patients (ages 68-95) wearing inertial sensor equipped shoes passed an instrumented walkway with and without gait support from a WW. The walkway assessed the risk of falling associated gait parameters velocity, swing time, stride length, stride time- and double support time variability. Inertial sensor-equipped shoes measured heel strike and toe off angles, and foot clearance. RESULTS: The use of a WW improved the risk of spatio-temporal parameters velocity, swing time, stride length and the sagittal plane associated parameters heel strike and toe off angles in all patients. First-time users (FTUs) showed similar gait parameter improvement patterns as frequent WW users (FUs). However, FUs with higher levels of gait impairment improved more in velocity, stride length and toe off angle compared to the FTUs. CONCLUSION: The impact of a WW can be quantified objectively by instrumented gait assessment. Thus, objective gait parameters may serve as surrogate markers for the use of walking aids in patients with gait and balance impairments.

Stride segmentation during free walk movements using multi-dimensional subsequence dynamic time warping on inertial sensor data.

Changes in gait patterns provide important information about individuals' health. To perform sensor based gait analysis, it is crucial to develop methodologies to automatically segment single strides from continuous movement sequences. In this study we developed an algorithm based on time-invariant template matching to isolate strides from inertial sensor signals. Shoe-mounted gyroscopes and accelerometers were used to record gait data from 40 elderly controls, 15 patients with Parkinson's disease and 15 geriatric patients. Each stride was manually labeled from a straight 40 m walk test and from a video monitored free walk sequence. A multi-dimensional subsequence Dynamic Time Warping (msDTW) approach was used to search for patterns matching a pre-defined stride template constructed from 25 elderly controls. F-measure of 98% (recall 98%, precision 98%) for 40 m walk tests and of 97% (recall 97%, precision 97%) for free walk tests were obtained for the three groups. Compared to conventional peak detection methods up to 15% F-measure improvement was shown. The msDTW proved to be robust for segmenting strides from both standardized gait tests and free walks. This approach may serve as a platform for individualized stride segmentation during activities of daily living.

Rasterstereographic evaluation of interobserver and intraobserver reliability in postsurgical adolescent idiopathic scoliosis patients.

STUDY DESIGN: Evaluation of rasterstereographic examinations in postsurgical adolescent scoliosis patients: a reliability study. OBJECTIVE: To investigate the interobserver and intraobserver reliability of rasterstereographic 3-dimensional back surface analysis and reconstruction of spine parameters including trunk length, trunk inclination, lateral deviation, kyphotic and lordotic angles in adolescent idiopathic scoliosis patients after scoliosis surgery. SUMMARY OF BACKGROUND DATA: The rasterstereography device formetric III 4D has been in routine clinical use for patients with scoliosis and other spinal deformities, reducing the patients' radiation exposure considerably. The reliability of this device has previously been examined in healthy volunteers but not in patients after scoliosis surgery. MATERIALS AND METHODS: Thirty-nine adolescent idiopathic scoliosis patients (32 women and 7 men) after scoliosis surgery with a mean age of 23.5 years (±10.6 y) were examined rasterstereographically by 5 investigators. Each investigator made a series of 3 measurements of each participating patient consecutively. The intraclass correlation coefficient (ICC) and the Pearson product moment correlation were calculated. In addition, the comparative analysis of the first and 15th measurements was assessed. RESULTS: The ICCs of all investigated parameters demonstrated very high interobserver and intraobserver reliability. The maximum ICC (0.988) for interobserver reliability of the 5 investigators was found for the trunk length and the minimum ICC (0.918) for lateral deviation. There were highly significant positive correlations between the first, second, and third measurements (r=0.994-0.697; P<0.001) for intraobserver reliability. Overall highly significant correlation was found comparing the results of the first and the 15th rasterstereographic measurement. CONCLUSIONS: The reliability of rasterstereography formetric III 4D in regard to the investigated parameters is excellent. The device can be used very efficiently by 1 or multiple investigators to analyze postsurgical adolescent idiopathic scoliosis patients in clinical practice, requiring only a single investigational exposure.

Frail Older Individuals Maintaining a Steady Standing Position: Associations Between Sway Measurements with Frailty Status Across Four Different Frailty Instruments.

OBJECTIVE: An analysis of the relationships between static equilibrium parameters and frailty status and/or severity across four different frailty measures. DESIGN: Cross-sectional analysis. SETTING: Geriatric wards of a general hospital. PARTICIPANTS: One hundred twenty-three geriatric inpatients comprising 70 women (56.5%) and 53 men (42.7%) with an age range of 68-95 years. METHODS: The variation in the center of pressure (CoP), ie, the length of sway, the area of sway, and the mean speed, was assessed for different positions/tasks: 1) wide standing with eyes open (WSEO); 2) wide standing with eyes closed (WSEC); 3) narrow standing with eyes open (NSEO) and 4) narrow standing with eyes closed (NSEC), using a force plate. Frailty status and/or frailty severity were evaluated using the frailty phenotype (FP), the clinical frailty scale (CFS), the 14-item frailty index based on a comprehensive geriatric assessment (FI-CGA), and a 47-item frailty index (FI). RESULTS: WSEO length of sway (FP, CFS, FI-CGA, FI), WSEO area of sway (FP, CFS, FI-CGA, FI), and WSEO mean speed (FP, CFS, FI-CGA, FI), WSEC length of sway (FP, FI-CGA, FI), WSEC area of sway (FP, FI-CGA, FI) and WSEC mean speed (FI-CGA, FI), NSEO length of sway (FP, FI-CGA, FI), NSEO area of sway (FP, CFS, FI-CGA, FI), and NSEO mean speed (FP, CFS, FI-CGA, FI), NSEC length of sway (FI-CGA, FI), NSEC area of sway (FI-CGA, FI) and NSEC mean speed (FI-CGA, FI) were associated with the frailty status and/or severity across the four different frailty instruments (all p < 0.05, respectively). CONCLUSION: Greater fluctuations in CoP with increasing frailty status and/or severity were a uniform finding across various major frailty instruments.

Mobile Stride Length Estimation With Deep Convolutional Neural Networks.

OBJECTIVE: Accurate estimation of spatial gait characteristics is critical to assess motor impairments resulting from neurological or musculoskeletal disease. Currently, however, methodological constraints limit clinical applicability of state-of-the-art double integration approaches to gait patterns with a clear zero-velocity phase. METHODS: We describe a novel approach to stride length estimation that uses deep convolutional neural networks to map stride-specific inertial sensor data to the resulting stride length. The model is trained on a publicly available and clinically relevant benchmark dataset consisting of 1220 strides from 101 geriatric patients. Evaluation is done in a tenfold cross validation and for three different stride definitions. RESULTS: Even though best results are achieved with strides defined from midstance to midstance with average accuracy and precision of , performance does not strongly depend on stride definition. The achieved precision outperforms state-of-the-art methods evaluated on the same benchmark dataset by . CONCLUSION: Due to the independence of stride definition, the proposed method is not subject to the methodological constrains that limit applicability of state-of-the-art double integration methods. Furthermore, it was possible to improve precision on the benchmark dataset. SIGNIFICANCE: With more precise mobile stride length estimation, new insights to the progression of neurological disease or early indications might be gained. Due to the independence of stride definition, previously uncharted diseases in terms of mobile gait analysis can now be investigated by retraining and applying the proposed method.

The Validity of Rasterstereography: A Systematic Review.

To investigate and monitor the progression of scoliosis and other spinal deformities in patients following idiopathic scoliosis (IS), non-invasive and radiation-free techniques are recommended because of the need for repeated radiographs. In a clinical setting, spine parameters can be quickly, cheaply and easily assessed using rasterstereography (RS). To assess the validity of the radiation-free technique RS based on surface topography compared with radiographs. MEDLINE, the Cochrane Library and EMBASE were systematically searched for studies which investigate the validity of rasterstereography compared with x-ray measurements. Studies published between January 1, 1990 and July 31, 2013 in English, German and French were included. Studies dealing with magnetic resonance imaging were excluded. Twelve studies with 570 patients were included; these articles were published between 1990 and 2013. The majority of studies investigated patients with IS, but other spinal pathologies included were thoracic hyperkyphosis and Scheuermann's disease. With regard to the quality assessment criteria for the included studies, three out of twelve studies were evaluated using a twelve point scale and two used a scale with eleven points. We conclude that RS facilitates clinical practice by analysing the spinal column. It is completely radiation-free and could help to monitor scoliosis progression.

Inertial sensor-based stride parameter calculation from gait sequences in geriatric patients.

A detailed and quantitative gait analysis can provide evidence of various gait impairments in elderly people. To provide an objective decision-making basis for gait analysis, simple applicable tests analyzing a high number of strides are required. A mobile gait analysis system, which is mounted on shoes, can fulfill these requirements. This paper presents a method for computing clinically relevant temporal and spatial gait parameters. Therefore, an accelerometer and a gyroscope were positioned laterally below each ankle joint. Temporal gait events were detected by searching for characteristic features in the signals. To calculate stride length, the gravity compensated accelerometer signal was double integrated, and sensor drift was modeled using a piece-wise defined linear function. The presented method was validated using GAITRite-based gait parameters from 101 patients (average age 82.1 years). Subjects performed a normal walking test with and without a wheeled walker. The parameters stride length and stride time showed a correlation of 0.93 and 0.95 between both systems. The absolute error of stride length was 6.26 cm on normal walking test. The developed system as well as the GAITRite showed an increased stride length, when using a four-wheeled walker as walking aid. However, the walking aid interfered with the automated analysis of the GAITRite system, but not with the inertial sensor-based approach. In summary, an algorithm for the calculation of clinically relevant gait parameters derived from inertial sensors is applicable in the diagnostic workup and also during long-term monitoring approaches in the elderly population.