Changes in Coordination and Its Variability with an Increase in Functional Performance of the Lower Extremities.

Clinical gait analysis has a long-standing tradition in biomechanics. However, the use of kinematic data or segment coordination has not been reported based on wearable sensors in "real-life" environments. In this work, the skeletal kinematics of 21 healthy and 24 neurogeriatric participants was collected in a magnetically disturbed environment with inertial measurement units (IMUs) using an accelerometer-based functional calibration method. The system consists of seven IMUs attached to the lower back, the thighs, the shanks, and the feet to acquire and process the raw sensor data. The Short Physical Performance Battery (SPPB) test was performed to relate joint kinematics and segment coordination to the overall SPPB score. Participants were then divided into three subgroups based on low (0-6), moderate (7-9), or high (10-12) SPPB scores. The main finding of this study is that most IMU-based parameters significantly correlated with the SPPB score and the parameters significantly differed between the SPPB subgroups. Lower limb range of motion and joint segment coordination correlated positively with the SPPB score, and the segment coordination variability correlated negatively. The results suggest that segment coordination impairments become more pronounced with a decreasing SPPB score, indicating that participants with low overall SPPB scores produce a peculiar inconsistent walking pattern to counteract lower extremity impairment in strength, balance, and mobility. Our findings confirm the usefulness of SPPB through objectively measured parameters, which may be relevant for the design of future studies and clinical routines.

Clusters of risk factors in metabolic syndrome and their influence on central blood pressure in a global study.

The effect of metabolic syndrome (MetS) and clusters of its components on central blood pressure (CBP) has not been well characterized. We aimed to describe the effect of MetS and clusters of its components on CBP in a large population and to identify whether this effect differs in men and women. We studied 15,609 volunteers (43% women) from 10 cohorts worldwide who participated in the Metabolic syndrome and Artery REsearch Consortium. MetS was defined according to the NCEP-ATP III criteria (GHTBW, glucose, high-density lipoprotein cholesterol, triglyceride, blood pressure, waist circumference). CBP was measured noninvasively and acquired from pulse wave analysis by applanation tonometry. MetS was associated with a 50% greater odds of having higher CSBP. After controlling for age, male sex, non HDL cholesterol, diabetes mellitus, and mean arterial pressure, only specific clusters of MetS components were associated with a higher CSBP; and some of them were significant in women but not in men. We identified "risky clusters" of MetS variables associated with high CSBP. Future studies are needed to confirm they identify subjects at high risk of accelerated arterial aging and, thus, need more intensive clinical management.

Different Effects of Vascular Aging on Ischemic Predisposition in Healthy Men and Women.

Invasive studies of the twentieth century showed the value of aortic pressure-time integrals as markers of myocardial oxygen demand and supply. More recent studies have used these concepts to evaluate the mechanisms of ischemic predisposition using noninvasive arterial tonometry in cardiology outpatients. We sought to evaluate the spectrum of myocardial oxygen demand and supply in a large cross-sectional community sample of healthy volunteers and identify the roles of age, sex, and wave reflection. Arterial tonometry was performed in 3682 healthy volunteers. Measures of systolic and diastolic pressure-time integrals and their ratio in addition to cardiac ejection duration were determined and analyzed by age and sex. Multiple regression analyses were performed to identify the mechanisms underlying observations, while controlling for confounders (heart rate, height, weight, and mean pressure). In a healthy cohort, older women more than men ( P<0.001) had unfavorable myocardial oxygen supply:demand ratios because of differing effects of vascular aging.