Most gait parameters decrease with age and are even more importantly reduced with frailty. However, other gait parameters exhibit different or even opposite trends for aging and frailty, and the underlying reason is unclear. Literature focuses either on aging, or on frailty, and a comprehensive understanding of how biomechanical gait regulation evolves with aging and with frailty seems to be lacking. We monitored gait dynamics in young adults (19–29 years, n = 27, 59% women), middle-aged adults (30–59 years, n = 16, 62% women), and non-frail (>60 years, n = 15, 33% women) and frail older adults (>60 years, n = 31, 71% women) during a 160 m walking test using the triaxial accelerometer of the Zephyr Bioharness 3.0 device (Zephyr Technology, Annapolis, MD, USA). Frailty was evaluated using the Frail Scale (FS) and the Clinical Frailty Scale (CFS). We found that in non-frail older adults, certain gait parameters, such as cadence, were increased, whereas other parameters, such as step length, were decreased, and gait speed is maintained. Conversely, in frail older adults, all gait parameters, including gait speed, were decreased. Our interpretation is that non-frail older adults compensate for a decreased step length with an increased cadence to maintain a functional gait speed, whereas frail older adults decompensate and consequently walk with a characteristic decreased gait speed. We quantified compensation and decompensation on a continuous scale using ratios of the compensated parameter with respect to the corresponding compensating parameter. Compensation and decompensation are general medical concepts that can be applied and quantified for many, if not all, biomechanical and physiological regulatory mechanisms of the human body. This may allow for a new research strategy to quantify both aging and frailty in a systemic and dynamic way.

The frailty syndrome is characterized by a decreased capacity to adequately respond to stressors. One of the most impaired physiological systems is the autonomous nervous system, which can be assessed through heart rate (HR) variability (HRV) analysis. In this article, we studied the chronotropic response (HR and HRV) to a walking test. We also analyzed HRV indices in rest as potential biomarkers of frailty. For this, a 160 m-walking test and two standing rest tests (before and after the walking) were performed by young (19–29 years old, n = 21, 57% women), middle-aged (30–59 years old, n = 16, 62% women), and frail older adults (>60 years old, n = 28, 40% women) and non-frail older adults (>60 years old, n = 15, 71% women), classified with the FRAIL scale and the Clinical Frailty Scale (CFS). Frequency domain parameters better allowed to distinguish between frail and non-frail older adults (low-frequency power LF, high-frequency power HF (nu), LF/HF ratio, and ECG-derived respiration rate EDR). Frail older adults showed an increased HF (nu) and EDR and a reduced LF (nu) and LF/HF compared to non-frail older adults. The increase in HF (nu) could be due to a higher breathing effort. Our results showed that a walk of 160 m is a sufficient cardiovascular stressor to exhibit an attenuated autonomic response in frail older adults. Several HRV indices showed to be potential biomarkers of frailty, being LF (nu) and the time required to reach the maximum HR the best candidates.

Antecedentes: La valoración de la fuerza muscular es de interés para la investigación de patologías como la fragilidad y la sarcopenia; sin embargo, el costo de algunos instrumentos necesarios para su evaluación podría ser una limitante en algunos escenarios. Objetivo: Comparar dos dinamómetros para comparar la concordancia entre las mediciones. Material y métodos: El estudio se realizó en una clínica ambulatoria de geriatría. Se evaluaron 120 participantes de 60 años y más provenientes de la comunidad. Se utilizó el dinamómetro manual hidráulico Jamar® y el dinamómetro manual digital Camry® EH101. Resultados: Se observó correlación positiva entre los dos instrumentos para la mano dominante (MD), con r de Pearson = 0.974 (p < 0.001) y ρ de Spearman = 0.973 (p < 0.001) para la mano no dominante (MND). El coeficiente de concordancia de Lin para la MD fue de 0.98 (p < 0.001) y para la MND, de 0.97 (p < 0.001) El coeficiente de correlación intraclase fue de 0.971 (IC 95 % = 0.95-0.97, p < 0.001) para MD y de 0.975 (IC 95 % = 0.96-0.98, p < 0.001) para MND. Conclusiones: El dinamómetro digital es un instrumento confiable para la medición de la fuerza de prensión en personas mayores de 60 años provenientes de la comunidad.

The quality of life (QoL) perception has been studied in neurological diseases; however, there is limited information linking brain morphological characteristics, QoL, and cognition. Human behavior and perception are associated with specific brain areas that interact through diffuse electrochemical networking. We used magnetic resonance imaging (MRI) to analyze the brain region volume (BRV) correlation with the scores of Rand’s 36-item Short Form Survey (SF-36) and cognitive domains (memory and dementia status). We analyzed data from 420 adult participants in the Maracaibo Aging Study (MAS). Principal component analysis with oblimin axis rotation was used to gather redundant information from brain parcels and SF-36 domains. Canonical correlation was used to analyze the relationships between SF-36 domains and BRV (adjusted for intracranial cavity), as well as sex, age, education, obesity, and hypertension. The average age (±SD) of subjects was 56 ± 11.5 years; 71% were female; 39% were obese; 12% had diabetes, 52% hypertension, and 7% dementia. No sex-related differences were found in memory and orientation scores, but women had lower QoL scores. The 1st and 2nd canonical correlation roots support the association of SF-36 domains (except social functioning and role emotional) and total brain volume, frontal lobe volume, frontal pole, lateral orbital lobe, cerebellar, and entorhinal areas. Other variables, including age, dementia, memory score, and systolic blood pressure, had a significant influence. The results of this study demonstrate significant correlations between BRV and SF-36 components, adjusted for covariates. The frontal lobe and insula were associated with the mental health component; the lateral-orbital frontal lobe and entorhinal area were correlated with the physical component.

Purpose Early detection of cognitive decline is essential for timely diagnosis and treatment. This study aimed to evaluate whether upper-limb movement dynamics derived from wrist-mounted inertial sensors during a fine motor task can accurately differentiate among healthy aging, mild cognitive impairment (MCI), and dementia (DEM). Methods The study recruited young and older participants. Cognitive status was established through clinical evaluation together with concordance across three standardized neurocognitive assessments (MMSE, MoCA, and NEUROPSI). Upper-limb dynamics during the Grooved Pegboard Test (GPT) were recorded using a wrist-mounted triaxial BioHarness accelerometer. Time- and frequency-domain features were extracted from the accelerometry signals, and uncorrelated linear discriminant analysis (ULDA) was applied for supervised dimensionality reduction. Classification performance was evaluated using support vector machine (SVM), random forest (RF), and k-nearest neighbors (KNN) classifiers using accuracy and area under the receiver operating characteristic curve (AUC-ROC). Results The study included 109 participants distributed into four groups: 30 young healthy subjects (YNG), 22 cognitively intact older adults (CIO), 27 participants with MCI, and 30 with DEM. Prior to dimensionality reduction, the SVM classifier achieved the strongest performance, reaching a macro accuracy of 0.88 ± 0.013, demonstrating meaningful discrimination using the original feature representation. ULDA-based projection further improved class separability across all evaluated models. RF + ULDA and SVM + ULDA achieved macro accuracies of 0.97, whereas KNN + ULDA achieved 0.94. Conclusion Fine motor dynamics measured during the GPT contain discriminative information associated with progressive cognitive decline and may support objective, wearable-sensor-based cognitive screening. Trial registration The Local Ethics Committee of the General Hospital of Mexico approved the study, “Dr. Eduardo Liceaga” (protocol code DI/23/110-B/03/12).

Background: Assessment of muscle strength is of great interest for the study of age-associated pathologies, including frailty and sarcopenia. However, the co...