Healthy Middle-aged Individuals Research Articles

Skeletal muscle reactive oxygen species and microvascular endothelial function in age-related hypertension: a study protocol using a microdialysis technique.

Increased reactive oxygen species (ROS) generation and microvascular endothelial disruptions occur with natural ageing, but often transpire before the detection of cardiometabolic conditions including hypertension. Age-related increases in blood pressure are driven by complex systemic changes with poorly understood integrated mechanisms. The deconditioning experienced by ageing skeletal muscle from mid-life is associated with reduced microvascular blood flow and increased peripheral resistance, suggesting that vasodilatory decrements in the muscle may precede the age-related increases in blood pressure. Structural and functional changes within the vascular and skeletal muscle systems with advancing age can influence redox homeostasis, and vice versa, further compounding microvascular endothelial dysfunction. Therefore, comparisons between the microvascular environments of healthy and hypertensive cohorts can provide insights into the changes that occur during significant periods of functional decline. This comprehensive study protocol describes a microdialysis technique to assess the interactions of microvascular health and functional changes in the muscle, which currently cannot be otherwise addressed. Here, we detail an experimental protocol to simultaneously detect skeletal muscle ROS (H2O2 and indirect O2 -), determine nutritive blood flow and assess microvascular endothelial function in response to acetylcholine stimulation. We expect that healthy middle-aged individuals should not have increased ROS generation in the muscle at rest, compared to their hypertensive or older counterparts, but may exhibit perturbed microvascular function. The described technique allows for intricate exploration of microvascular physiology that will provide a critically novel insight into benchmarking potential age-related mechanisms involved in the development of age-related hypertension, and aid in early identification and prevention. KEY POINTS: Increased reactive oxygen species (ROS) production and microvascular endothelial dysfunction precede the onset of age-related cardiometabolic and vascular conditions such as hypertension. The profound structural and functional changes that occur within the vasculature and in skeletal muscle from middle age prompt a need to mechanistically explore the microvascular environment in healthy and hypertensive individuals. Using a novel microdialysis technique, we detail an experimental protocol to simultaneously detect skeletal muscle ROS (H2O2 and indirect O2 -), determine nutritive blood flow and assess microvascular endothelial function in response to acetylcholine stimulation. With this technique and study protocol, we can reveal functional insights into potential perturbations in ROS generation at rest and the microvascular endothelium, which play important roles in the development of age-related hypertension.

COVID-19 is associated with cardiac structural and functional remodelling in healthy middle-aged and older individuals.

Coronavirus disease 2019 (COVID-19) was declared a global pandemic in 2019. It remains uncertain to what extent COVID-19 effects the heart in heathy individuals. To evaluate the effect of the COVID-19 on cardiac structure and function in middle-aged and older individuals. A single-centre prospective observational study enroled a total of 124 participants (84 with history of COVID-19 [COVID-19 group] and 40 without a history of COVID-19 [non-COVID group]). All participants underwent echocardiography with speckle tracking to assess cardiac structure and function at rest and during peak exercise. There were no differences in left and right ventricular diastolic function (p ≥ 0.05) between the COVID-19 and non-COVID-19 groups. Participants in COVID-19 group demonstrated higher left ventricular mass (130 ± 39.8 vs. 113 ± 27.2 g, p = 0.008) and relative wall thickness (0.38 ± 0.07 vs. 0.36 ± 0.13, p = 0.049). Left ventricular global longitudinal strain was reduced in the COVID-19 group at rest and at peak-exercise (rest: 18.3 ± 2.01 vs. 19.3 ± 1.53%, p = 0.004; peak exercise: 19.1 ± 2.20 vs. 21.0 ± 1.58%, p ≤ 0.001). However, no difference was seen in resting left ventricular ejection fraction (58 ± 2.89 vs. 59 ± 2.51%, p = 0.565) between groups. Right ventricular fractional area change was reduced in the COVID-19 group (p = 0.012). Cardiac structural and functional remodelling was observed in middle-aged and older otherwise healthy individuals with a history of COVID-19.

Spatiotemporal Gait Characteristics and Neuropsychological Performance in Midlife

Abstract Background Midlife risk factors such as Type 2 Diabetes Mellitus (T2DM) confer a significantly increased risk of cognitive impairment in later life, with executive function, memory and attention domains often affected first. Spatiotemporal gait characteristics are increasingly recognised as biomarkers of neurocognitive function and later dementia risk. Methods Using an automated walkway, 24 spatiotemporal gait parameters were examined across 5 domains of gait previously linked to cognitive function on usual-pace, maximal-pace, and cognitive dual-task gait conditions. Neurocognitive function was measured using a neuropsychological assessment battery. Linear regression was used assess the relationship between each gait parameter across the three walks and cognitive function. Results 102 middle-aged adults underwent assessment, 65 with uncomplicated T2DM (57.5 ± 8.0 years; 40% female) and 37 healthy controls (57.0 ± 8.3 years; 62.1% female). T2DM was associated with significant changes in gait phases and rhythm domains at usual-pace, and greater gait variability observed during maximal-pace and dual-task. In the overall cohort, both gait pace and rhythm domains were associated with memory and executive function during usual pace walking. At maximal-pace, gait pace parameters were associated with reaction time and delayed memory. During the cognitive dual-task, associations between gait variability and delayed memory and executive function were observed. Associations persisted following covariate adjustment and did not differ by T2DM status. Conclusion This supports the use of spatiotemporal gait as an integrative biomarker of neurocognitive function in otherwise healthy middle-aged individuals. Discrete associations were seen between both differing gait tasks and gait domains with domain-specific neuropsychological performance. Employing both maximal-pace and dual-task paradigms, in addition to single-task usual-pace gait, may be important in cognitively unimpaired populations with risk factors for later cognitive decline - with the aim of identifying individuals who may benefit most from potential preventative interventions.

MRI-based assessment paraspinal extensor muscle fatty infiltration in acute cervical spinal cord injury patients - a retrospective study

BackgroundThe effect of fat infiltration in the paraspinal muscles on cervical degenerative disease has been confirmed by multiple studies. However, little is known about fat infiltration in the paraspinal extensors in patients with acute cervical spinal cord injury (SCI). This study aimed to investigate the difference in paraspinal extensor fatty infiltration between patients with acute cervical SCI and healthy controls, and to further explore the protective role of the paravertebral extensor muscles in patients with cervical SCI.MethodsA total of 50 patients with acute cervical SCI admitted to the emergency department from January 2019 to November 2023 were retrospectively analyzed, including 26 males and 24 females, with an average age of 59.60 ± 10.81 years. A control group of 50 healthy middle-aged and elderly individuals was also included, comprising 28 males and 22 females, with an average age of 55.00 ± 8.21 years. Cervical spine magnetic resonance imaging (MRI) was used to measure the cross-sectional areas of the superficial and deep cervical extensor muscles, the corresponding vertebral body cross-sectional areas, and the fat area within the superficial and deep extensor muscle groups using Image J software. Differences between the two groups were compared, and the cervical SCI patients were further analyzed based on the severity of the spinal cord injury and gender differences.ResultsThe deep fatty infiltration ratio (DFIR) and superficial fatty infiltration ratio (SFIR) at C4-C7 in the cervical SCI group were significantly higher than those in the control group (P < 0.001). The cross-sectional area of the functional deep extensor area (FDEA) relative to the vertebral body area (VBA) and the cross-sectional area of the functional superficial extensor area (FSEA) relative to the VBA at the C5 and C6 levels in the cervical SCI group were significantly lower than those in the control group (P < 0.001, P < 0.001, P = 0.034, P = 0.004 respectively). Among the cervical SCI patients, the cross-sectional areas of the deep extensor area (DEA) and the superficial extensor area (SEA) in males were significantly higher than those in females (P < 0.001). At the C6 and C7 levels, the FDEA/VBA and FSEA/VBA ratios in the male group were higher than those in the female group (P = 0.009, P = 0.022, P = 0.019, P = 0.005, respectively).ConclusionPatients with acute cervical SCI exhibit significantly higher fatty infiltration and a greater degree of paravertebral extensor muscle degeneration compared to healthy controls. This finding underscores the importance of the paravertebral extensor muscles in the context of cervical SCI and may guide future therapeutic strategies.

Unidirectional association of clonal hematopoiesis with atherosclerosis development

Clonal hematopoiesis, a condition in which acquired somatic mutations in hematopoietic stem cells lead to the outgrowth of a mutant hematopoietic clone, is associated with a higher risk of hematological cancer and a growing list of nonhematological disorders, most notably atherosclerosis and associated cardiovascular disease. However, whether accelerated atherosclerosis is a cause or a consequence of clonal hematopoiesis remains a matter of debate. Some studies support a direct contribution of certain clonal hematopoiesis-related mutations to atherosclerosis via exacerbation of inflammatory responses, whereas others suggest that clonal hematopoiesis is a symptom rather than a cause of atherosclerosis, as atherosclerosis or related traits may accelerate the expansion of mutant hematopoietic clones. Here we combine high-sensitivity DNA sequencing in blood and noninvasive vascular imaging to investigate the interplay between clonal hematopoiesis and atherosclerosis in a longitudinal cohort of healthy middle-aged individuals. We found that the presence of a clonal hematopoiesis-related mutation confers an increased risk of developing de novo femoral atherosclerosis over a 6-year period, whereas neither the presence nor the extent of atherosclerosis affects mutant cell expansion during this timeframe. These findings indicate that clonal hematopoiesis unidirectionally promotes atherosclerosis, which should help translate the growing understanding of this condition into strategies for the prevention of atherosclerotic cardiovascular disease in individuals exhibiting clonal hematopoiesis.

Clonal hematopoiesis dynamics and subclinical atherosclerosis in healthy middle-aged individuals

Clonal hematopoiesis dynamics and subclinical atherosclerosis in healthy middle-aged individuals

Changes in appetite during acute passive intermittent and continuous hypoxemia in postprandial and fasting states: A combined analysis of four laboratory-based randomized crossover trials

Hypoxemia occurs during exposure to high altitude (continuous hypoxemia) or in the context of breathing disorders such as obstructive sleep apnea (OSA; intermittent hypoxemia). Growing evidence demonstrates that hypoxemia induces an anorexigenic effect on appetite; however, few studies have assessed hypoxemia-related reductions in appetite during acute passive exposures and during intermittent hypoxemia. This study thus pooled together four same-single-site randomized crossover trials using simulated models of high altitude (fraction of inspired oxygen = 0.1200, ∼5000 m) and moderate OSA (∼15 hypoxemic cycles per hour, ∼85 oxyhemoglobin saturation). Changes in appetite were evaluated during 6 h of passive normoxia and intermittent or continuous hypoxemia in postprandial or fasting states among healthy young adults (n = 40) and middle-aged individuals living with OSA (n = 7). Our results demonstrate that (1) acute passive intermittent hypoxemia leads to statistically significant, but likely not clinically significant reductions in appetite in the postprandial state, (2) the anorexigenic effect of acute passive hypoxemia on appetite is not consistent across hypoxemic methods and nutritional states, and (3) variations in individual factors may influence appetite responses during normoxia and hypoxemia. These findings indicate that the effect of acute passive hypoxemia on appetite is heterogeneous, particularly across different hypoxemic methods and nutritional states.

Is There a Relationship of Cortisol and Sex Steroid Hormones With Mental Health in Middle-Aged Adults? The FIT-AGEING Study

ObjectiveMental health has emerged as a worldwide concern given the increasing incidence of anxiety and depression disorders in the last years. Cortisol and sex steroid hormones have been demonstrated to be important regulators of mental health processes in older adults. However, the evidence considering these integrated variables in apparently healthy middle-aged individuals has not been thoroughly addressed. The present study aimed to investigate the association of the plasma cortisol, testosterone, free testosterone, sex hormone–binding globulin (SHBG), and dehydroepiandrosterone sulfate (DHEAS) levels with mental health in middle-aged adults. MethodsThis cross-sectional study included a cohort of 73 middle-aged adults aged 45 to 65 years (women, 53%). Plasma cortisol, testosterone, SHBG, and DHEAS were assessed using a competitive chemiluminescence immunoassay. Free testosterone was calculated from the total testosterone and SHBG. Self-reported depression severity, generic health-related quality of life, hope, satisfaction with life, and optimism-pessimism were evaluated using the Beck Depression Inventory-II (BDI-II), 36-Item Short-Form Health Survey, Adult Hope Scale, Satisfaction with Life Scale, and Life Orientation Test-Revised, respectively—with higher total scores of these scales indicating greater levels of these variables. ResultsThe testosterone and free testosterone levels were inversely associated with the BDI-II values in men (all P ≤ .042). The cortisol levels were positively related with the Satisfaction with Life Scale scores, whereas the testosterone, free testosterone, SHBG, and DHEAS levels were negatively correlated with the BDI-II values in women (all P ≤ .045). ConclusionIn summary, these results suggest that the increased levels of steroid hormones—within the normal values—are associated with better mental health in middle-aged adults.

Discrete Relationships between Spatiotemporal Gait Characteristics and Domain-Specific Neuropsychological Performance in Midlife.

Midlife risk factors such as type 2 diabetes mellitus (T2DM) confer a significantly increased risk of cognitive impairment in later life with executive function, memory, and attention domains often affected first. Spatiotemporal gait characteristics are emerging as important integrative biomarkers of neurocognitive function and of later dementia risk. We examined 24 spatiotemporal gait parameters across five domains of gait previously linked to cognitive function on usual-pace, maximal-pace, and cognitive dual-task gait conditions in 102 middle-aged adults with (57.5 ± 8.0 years; 40% female) and without (57.0 ± 8.3 years; 62.1% female) T2DM. Neurocognitive function was measured using a neuropsychological assessment battery. T2DM was associated with significant changes in gait phases and rhythm domains at usual pace, and greater gait variability observed during maximal pace and dual tasks. In the overall cohort, both the gait pace and rhythm domains were associated with memory and executive function during usual pace. At maximal pace, gait pace parameters were associated with reaction time and delayed memory. During the cognitive dual task, associations between gait variability and both delayed memory/executive function were observed. Associations persisted following covariate adjustment and did not differ by T2DM status. Principal components analysis identified a consistent association of slower gait pace (step/stride length) and increased gait variability during maximal-pace walking with poorer memory and executive function performance. These data support the use of spatiotemporal gait as an integrative biomarker of neurocognitive function in otherwise healthy middle-aged individuals and reveal discrete associations between both differing gait tasks and gait domains with domain-specific neuropsychological performance. Employing both maximal-pace and dual-task paradigms may be important in cognitively unimpaired populations with risk factors for later cognitive decline-with the aim of identifying individuals who may benefit from potential preventative interventions.

Eligibility for lipid-lowering therapy when applying systemic coronary risk estimation 2 according to guidelines on apparently healthy middle-aged individuals.

To estimate the proportion eligible for lipid-lowering therapy (LLT) when using the systemic coronary risk estimation 2 (SCORE2) on apparently healthy individuals. Individuals aged 50-64 years were randomly invited to The Swedish Cardiopulmonary Bioimage Study (n = 30 154). Participants with previous atherosclerotic cardiovascular disease (CVD), diabetes mellitus, or chronic kidney disease were excluded. The 10-year risk of CVD was estimated using the SCORE2 equation and the multicell chart. Eligibility for LLT was estimated according to the 2021 European Society of Cardiology CVD prevention guidelines. Presence of coronary atherosclerosis was determined using coronary computed tomography angiography (CCTA). Among 26 570 apparently healthy individuals, 32% had high and 4% had very high 10-year CVD risk, according to the SCORE2 equation. Among high- and very-high-risk individuals, 99% had low-density lipoprotein cholesterol levels above guideline goals making 35% of the total population eligible for LLT. Of those eligible, undergoing imaging, 38% had no signs of coronary atherosclerosis according to CCTA. Using the SCORE2 chart, 52% of the population were eligible for LLT, of which 44% had no signs of coronary atherosclerosis. In those with high or very high risk, ongoing LLT was reported in 7% and another 11% received LLT within 6 months after study participation. Nearly all apparently healthy individuals with high and very high CVD risk, or 35% of the total population, were eligible for LLT according to guidelines, and a large proportion had no signs of atherosclerosis. Compared with the SCORE2 equation, the SCORE2 chart resulted in more individuals being eligible for LLT.

Reference ranges for ambulatory heart rate measurements in a middle-aged population

BackgroundElevated heart rate (HR) predicts cardiovascular disease and mortality, but there are no established normal limits for ambulatory HR. We used data from the Swedish CArdioPulmonary Imaging Study to determine...

APOL1 Kidney Risk Variants and Long-Term Kidney Function in Healthy Middle-Aged Black Individuals: The Atherosclerosis Risk in Communities (ARIC) Study

Rationale and ObjectiveImpact of Apolipoprotein L1(APOL1) genotype on future risk of kidney disease among middle-aged individuals with good kidney function is not well established. Study DesignLongitudinal cohort study. Setting & Participants5,886 healthy individuals, 45-64 years old, enrolled in the Atherosclerosis Risk in Communities study with eGFRcr ≥ 80 mL/min who would be suitable kidney donors. ExposuresRace and APOL1 genotype OutcomesEGFRcr-cys using CKD-EPI 2021 equation, uACR, proportion with CKD 3a or worse, ESKD and death. Analytical ApproachParticipants grouped on race and APOL1 genotype. Compared eGFRcr-cys and uACR across groups. Multinomial logistic regression models were used compare odds of CKD. Kaplan-Meier survival curves were created to compare rates of ESKD and death at last follow-up. ResultsThere were 5,075 whites (86%), 701 Blacks carrying low-risk APOL1 genotype (12%) and 110 Blacks carrying high-risk APOL1 genotype (2%). The mean age at baseline was 53±6 years. At 10 years, white participants had lower eGFRcr-cys than low-risk and high-risk groups (89±16 vs. 91±16 and 92±15 mL/min/1.73m2, respectively; p <0.001). At 25 years, white participants continued to have lower eGFRcr-cys than low-risk group (70±18 vs. 72±19 mL/min/1.73m2; p <0.001) but not compared to high risk APOL1 genotype (67±23 mL/min/1.7m2). There was no difference in uACR among groups at 10 and 25 years (p=0.87 and 0.91 respectively). The odds of developing CKD Stage 3a or worse were not different between low-risk and high-risk APOL1 group in both unadjusted and adjusted models (p=0.26 and p=0.39, respectively). At last follow-up, < 5% developed ESKD and 45% of individuals either died or reached ESKD with no difference in outcomes between the groups. LimitationsLow ascertainment due to death and long follow-up ConclusionsAmong middle-aged individuals, APOL1 genotype does not appear to be a major driver of future risk of kidney disease.

Associations between antipsychotics-induced weight gain and brain networks of impulsivity

Given the unpredictable rapid onset and ubiquitous consequences of weight gain induced by antipsychotics, there is a pressing need to get insights into the underlying processes at the brain system level that will allow stratification of “at risk” patients. The pathophysiological hypothesis at hand is focused on brain networks governing impulsivity that are modulated by neuro-inflammatory processes. To this aim, we investigated brain anatomy and functional connectivity in patients with early psychosis (median age: 23 years, IQR = 21–27) using anthropometric data and magnetic resonance imaging acquired one month to one year after initiation of AP medication. Our analyses included 19 patients with high and rapid weight gain (i.e., ≥5% from baseline weight after one month) and 23 patients with low weight gain (i.e., <5% from baseline weight after one month). We replicated our analyses in young (26 years, IQR = 22–33, N = 102) and middle-aged (56 years, IQR = 51–62, N = 875) healthy individuals from the general population. In early psychosis patients, higher weight gain was associated with poor impulse control score (β = 1.35; P = 0.03). Here, the observed brain differences comprised nodes of impulsivity networks - reduced frontal lobe grey matter volume (Pcorrected = 0.007) and higher striatal volume (Pcorrected = 0.048) paralleled by disruption of fronto-striatal functional connectivity (R = −0.32; P = 0.04). Weight gain was associated with the inflammatory biomarker plasminogen activator inhibitor-1 (β = 4.9, P = 0.002). There was no significant association between increased BMI or weight gain and brain anatomy characteristics in both cohorts of young and middle-aged healthy individuals. Our findings support the notion of weight gain in treated psychotic patients associated with poor impulse control, impulsivity-related brain networks and chronic inflammation.

Singing Habit Potentially Prevents the Oral Frailty of Japanese Healthy Middle-Aged and Elderly Individuals

BACKGROUND: Focus has recently been placed on the importance of taking measures against the oral frailty of healthy elderly individuals.&#x0D; &#x0D; OBJECTIVE: To exploratorily examine the association of singing habit with the oral frailty of Japanese healthy middle-aged and elderly subjects.&#x0D; &#x0D; METHODS: Self-reported questionnaire surveys on singing habit, oral frailty, social isolation, and depressive tendency were conducted. Pearson&amp;rsquo;s correlation coefficients were calculated, and simple linear regression analysis assessed the association of an independent variable (singing habit scores) with a dependent variable [oral frailty index (OFI)-8 scores], while multiple linear regression analysis assessed the associations of independent variables (age, gender, as well as the presence or absence of singing habit, social isolation, and depressive tendency) with the OFI-8 scores.&#x0D; &#x0D; RESULTS: 32 subjects (6 males and 26 females; mean age, 69.0&amp;plusmn;5.6 years) participated in the surveys. The OFI-8 scores ranged from 0 to 11 points (mean score: 3.3&amp;plusmn;2.3 points), with the most predominant score of 4 points (8/32, 25.0%). Simple linear regression analysis (n=32) revealed that singing habit significantly lowered the OFI-8 scores (p=0.045), although no correlation was detected (R2=0.1269). Multiple linear regression analysis (n=31) revealed that singing habit showed a moderate inverse correlation (b, -1.73; r=-0.44) with and significantly lowered the OFI-8 scores (p=0.03), suggesting its potential of reducing the risk of oral frailty. Age, social isolation, and depressive tendency had no significant association with the OFI-8 scores.&#x0D; &#x0D; CONCLUSION: The present exploratory study does not provide conclusive evidence about oral frailty prevention by singing habit but affords underpinnings for further research.&#x0D; &#x0D; Keywords: Singing Habit, Oral Frailty, Depression, Social Isolation, Healthy Middle-Aged and Elderly Individuals, Self-reported Questionnaire Surveys

PEARL-Neuro Database: EEG, fMRI, health and lifestyle data of middle-aged people at risk of dementia

Interdisciplinary approaches are needed to understand the relationship between genetic factors and brain structure and function. Here we describe a database that includes genetic data on apolipoprotein E (APOE) and phosphatidylinositol binding clathrin assembly protein (PICALM) genes, both of which are known to increase the risk of late-onset Alzheimer's disease, paired with psychometric (memory, intelligence, mood, personality, stress coping strategies), basic demographic and health data on a cohort of 192 healthy middle-aged (50–63) individuals. Part of the database (~79 participants) also includes blood tests (blood counts, lipid profile, HSV virus) and functional neuroimaging data (EEG/fMRI) recorded with a resting-state protocol (eyes open and eyes closed) and two cognitive tasks (multi-source interference task, MSIT; and Sternberg's memory task). The data were validated and showed overall good quality. This open-science dataset is well suited not only for research relating to susceptibility to Alzheimer's disease but also for more general questions on brain aging or can be used as part of meta-analytical multi-disciplinary projects.

Intake of palmitic acid and its association with metabolic flexibility in middle-aged individuals: a preliminary study

Objective This study aimed to assess the relationship between dietary palmitic acid (PA) intake and its association with body fat deposition and metabolic flexibility (MF) in middle-aged healthy individuals. Methods Fifteen healthy participants (n = 15; 6 males, 9 females) with a mean age of 54 were enlisted. They were subjected to graded exercise tests using a cycle ergometer coupled with a calorimeter. Respiratory gas exchange was evaluated to determine two MF parameters. First, the MF index was derived by multiplying peak fatty acid oxidation (PFO) per kg of fat-free mass (FFM) with the percentage of VO2max at PFO. The second parameter, peak energy substrates’ oxidation (aka PESO), was computed by aggregating the kilocalories from PFO and peak carbohydrate oxidation, normalized per kg FFM. Dietary intake was gauged using a 7-day dietary record. Spearman’s regression was employed to analyze the association between dietary intake of specific fat classes, PA, MF parameters, and body fat percentage. Results Preliminary results demonstrate that dietary saturated fatty acids (SFA) within physiological limits correlate with enhanced substrate oxidation capacity. This suggests augmented MF in middle-aged subjects. Among dietary SFA, PA was identified as the primary factor in this favorable correlation. Conclusions Our initial observations, even though preliminary, strongly suggest a beneficial association between PA intake, MF, and body fat percentage. This underscores the potential nutritional importance of PA in promoting MF. Significance Statement Disparities in data regarding the health effects of dietary fats may arise from the distinct roles various dietary fatty acids play in MF.

Gait Imbalances of Middle-Aged Sedentary Populations

Walking is the first locomotor movement developed by humans after reflexive movements and balancing processes. This study aimed to evaluate walking patterns of middle-aged individuals who lead a sedentary life and to compare gait parameters in terms of gender and body mass index. This study contained eighty-four voluntarily participants (30.00±6.94 years; 74.02±15.44 kg; 170.23±8.94 cm). All participants were sedentary individuals who had not undergone any lower extremity surgery, did not use any movement system medication. Height was assessed by using a wall-mounted stadiometer. Weight was assesed by using Tanita TBF-300. Gait Analysis were performed by Microgate Optogait. All tests were carried out in the same air-conditioned lab which was set to 20°C and 1890 m altitude. Gait parameters were directly provided from Microgate Optogait. The differences between women and men, fat and normal weight were determined using an analysis of variance with Independent T test. All the data were shown as mean and standard deviation. In statistical analysis, the level of significance was chosen as p&amp;lt;0.05. There was no significantly difference, when gait parameters values was compared according to gender and BMI (p&amp;gt;0.05) in all parameters. There was just significantly difference contact phase and propulsive phase according to gender and double support phase according to BMI. There was also bilaterally difference contact phase, the overweights had more imbalance and interestingly in favor of the non-dominant limb. The mean values of the gait values obtained were similarly the norm values of healthy middle-aged individuals.

Similarity between structural and proxy estimates of brain connectivity

Functional magnetic resonance and diffusion weighted imaging have so far made a major contribution to delineation of the brain connectome at the macroscale. While functional connectivity (FC) was shown to be related to structural connectivity (SC) to a certain degree, their spatial overlap is unknown. Even less clear are relations of SC with estimates of connectivity from inter-subject covariance of regional F18-fluorodeoxyglucose uptake (FDGcov) and grey matter volume (GMVcov). Here, we asked to what extent SC underlies three proxy estimates of brain connectivity: FC, FDGcov and GMVcov. Simultaneous PET/MR acquisitions were performed in 56 healthy middle-aged individuals. Similarity between four networks was assessed using Spearman correlation and convergence ratio (CR), a measure of spatial overlap. Spearman correlation coefficient was 0.27 for SC-FC, 0.40 for SC-FDGcov, and 0.15 for SC-GMVcov. Mean CRs were 51% for SC-FC, 48% for SC-FDGcov, and 37% for SC-GMVcov. These results proved to be reproducible and robust against image processing steps. In sum, we found a relevant similarity of SC with FC and FDGcov, while GMVcov consistently showed the weakest similarity. These findings indicate that white matter tracts underlie FDGcov to a similar degree as FC, supporting FDGcov as estimate of functional brain connectivity.

Brain Connectivity Correlates of Cognitive Dispersion in a Healthy Middle-Aged Population: Influence of Subjective Cognitive Complaints.

Cognitive dispersion, representing intraindividual fluctuations in cognitive performance, is associated with cognitive decline in advanced age. We sought to elucidate sociodemographic, neuropsychological, and brain connectivity correlates of cognitive dispersion in middle age, and further consider potential influences of the severity of subjective cognitive complaints (SCC). Five hundred and twenty healthy volunteers from the Barcelona Brain Health Initiative (aged 40-66 years; 49.6% females, 453 with magnetic resonance imaging acquisitions) were included and stratified into high and low SCC groups. Two analysis steps were undertaken: (1) for the whole sample and (2) by groups. Generalized linear models and analysis of covariance were implemented to study associations between cognitive dispersion and performance (episodic memory, speed of processing, and executive function), white matter integrity, and resting-state functional connectivity (rs-FC) of the default mode network (DMN) and dorsal attentional networks (DAN). Across-domain dispersion was negatively related to cognitive performance, rs-FC within the DMN, and between the DMN and the DAN, but not to white matter integrity. The rs-FC values were not explained by cognitive performance. When considering groups, the above findings were significant only for those with high SCC. In healthy middle-aged individuals, high cognitive dispersion was related to poorer cognition and DMN dysregulation, being these associations stronger among subjects with high SCC. The present results reinforce the interest in considering dispersion measures within neuropsychological evaluations, as they may be more sensitive to incipient age-related cognitive and functional brain changes than traditional measures of performance.

Higher serum uric acid is associated with poorer cognitive performance in healthy middle-aged people: a cross-sectional study

Age-related cognitive impairment can occur many years before the onset of the clinical symptoms of dementia. Uric acid (UA), a metabolite of purine-rich foods, has been shown to be positively associated with improved cognitive function, but such association remains controversial. Moreover, most of the previous studies investigating the association included elderly participants with memory-related diseases. Therefore, the present study aimed at investigating whether serum UA (sUA) is associated with cognitive performance in healthy middle-aged individuals. We conducted a cross-sectional study on a cohort of middle-aged individuals (40–60 years old) who participated in the Qatar Biobank. The participants had no memory-related diseases, schizophrenia, stroke, or brain damage. They were divided according to sUA level into a normal group (< 360 μmol/L) and a high group (≥ 360 μmol/L), and underwent an assessment of cognitive function using the Cambridge Neuropsychological Test Automated Battery. Two cognitive function domains were assessed: (a) speed of reaction/reaction time and (b) short-term visual memory. The median age of the 931 participants included in the study was 48.0 years (IQR: 44.0, 53.0), of which 47.6% were male. Adjusted multivariable linear regression analyses showed that higher sUA is associated with poorer performance on the visual memory domain of cognitive function (β = − 6.87, 95% CI − 11.65 to − 2.10, P = 0.005), but not on the speed of reaction domain (β = − 55.16, 95% CI − 190.63 to 80.30, P = 0.424). Our findings support previous studies suggesting an inverse association between high sUA levels and cognitive function in elderly and extend the evidence for such a role to middle-aged participants. Further prospective studies are warranted to investigate the relationship between UA and cognition.