Age-related Phenomena Research Articles

Family values: youth’s attitudes vs older generation

The article presents the results of the sociological research conducted in 2024 and based on a qualitative methodology (18 in-depth interviews), all-Russian survey data, as well as research made by Russian scientists. The main purpose of the study is to identify the attitudes of young generations (aged 18-35) and older people (aged 60+) to marriage, family, children, divorce, use of digital technologies based on a comparative analysis. The results of the study show that the assertion that exists in public discourse about the loss of “traditional family values” by the younger generation is premature; rather, we should talk about their transformation in the context of the political and economic crisis under the influence of a higher degree of responsibility of young people in creating their own family and having children, pragmatism, and a critical assessment of their own capabilities. Currently, the problems of the older people are increasingly included in the agenda of modern state social policy in order to include them in various types of activities (education, mentoring, volunteering) to overcome loneliness, prevent destructive age-related phenomena, maintain physical and mental health, increase life expectancy, improve adaptive capabilities, which allows maintaining the connection between generations in difficult socio-economic and political conditions.

Investigating the Performance of a Degraded Prestressed Concrete Box Girder Half-joint Bridge in the Spirit of the Italian Guidelines

The paper investigates a paired pre-stressed box-girder concrete bridge, according to the framework suggested by the new Italian Guidelines for the risk assessment of existing bridges. The bridges, selected as case study within the research agreement signed by the FABRE Consortium and ANAS S.p.A. for first applications of the Italian Guidelines, present significant age-related degradation phenomena known to the Administrator, who decided for the bridges demolition and reconstruction. Visual inspections confirmed defects in the pre-stressing system, a permanent deflection of the deck, and cracks at half-joints, possibly due to pre-stressing loss and creep effects triggered by the poor quality of concrete. Also, preliminary safety verifications revealed not to meet code requirements in most cross-sections. Consequently, the most degraded bridge was closed. From March 2022, experimental campaigns have been performed by the FABRE Consortium and ANAS for improving their experience on the behaviour of old pre-stressed concrete bridges, as well as to control possible performance loss of the open bridge, sustaining the overall route traffic. The paper summarises these activities and presents some possible future investigations to be carried out before bridge demolition.

Post-polio syndrome is not a dysimmune condition.

Poliomyelitis is a global disabling disease affecting 12-20 million of people. Post poliomyelitis syndrome (PPS) may affect up to 80% of polio survivors: increased muscle weakness, pain, fatigue, functional decline. It relies on aging of an impaired neuro-muscular system with ongoing denervation processes. A late involvement of humoral or cellular pro-inflammatory phenomena is also suspected. To assess the dysimmune hypothesis of PPS by comparing lymphocyte subpopulations and humoral immune factors between PPS patients and controls. Cross-sectional study. Montpellier University Hospital. Forty-seven PPS and 27 healthy controls. PPS patients and controls were compared on their lymphocyte subpopulations and humoral immune factors (IL-1β, IL-6, IL-8, IL-17, IL-21, IL-22, IL-23, IFN-γ, TNF-α, GM-CSF, RANTES, MCP1, MIP-3a, IL-10, TGF-β, IL4, IL13). Patients were further compared according to their dominant clinical symptoms. Sample size guaranteed a power >90% for all comparisons. PPS patients and controls were comparable in gender, age and corpulence. Most patients had lower limb motor sequelae (N.=45, 95.7%), a minority had upper limb motor impairment (N.=16, 34.0%). Forty-five were able to walk (94%), 35/45 with technical aids. The median of the two-minute walking test was 110 meters (interquartile range 55; 132). Eighteen (38%) required help in their daily life. Their quality of life was low (SF36). All described an increased muscular weakness, 40 (85%) a general fatigue, and 39 (83%) muscular or joint pain. Blood count, serum electrolytes, T and B lymphocyte subpopulations and cytokines were comparable between patients and controls, except for creatine phospho kinase that was significantly higher in PPS patients. None of these variables differed between the 20/47 patients whose late main symptoms were pain or fatigue, and other patients. Our results suggest that PPS is not a dysimmune disease. Our results do not sustain immunotherapy for PPS. Our work suggest that PPS may be mostly linked to physiological age-related phenomena in a disabled neuromuscular condition. Thus, our results emphasize the role of prevention and elimination of aggravating factors to avoid late functional worsening, and the importance of rehabilitation programs that should be adapted to patients' specific conditions.

Exploring age-related phenomena in VR-based teleoperations: a human-centered perspective for industry 5.0

ABSTRACT The increasingly aging workforce is bringing particular attention to senior individuals in production sectors. While the interest in Virtual Reality (VR) applications for industrial robotics grows, the question of whether and how senior workers can withstand VR-based repetitive tasks arises. We here aimed to answer such questions by systematically assessing young and senior users’ experiential, behavioural, and cognitive factors during simulated robotic teleoperations in VR. Two control systems for VR telerobotics, button- and action-based controls, were employed. Human performance, vigilance, and workload were measured through self-reports and a VR-integrated eye-tracker. Additionally, age-dependent differences in individual cultural and experiential factors were explored via self-report measures. Despite being slower and experiencing increased fatigue under specific conditions, as suggested by the eye-tracking measures, senior users demonstrated comparable precision in operating the robotic arm to their younger counterparts. Notably, both age groups reported similar levels of perceived fatigue. The paper provides an in-depth analysis of the advantages and challenges of adopting advanced telerobotics control systems across different age groups, consistently emphasising the human-centered dimension.

The Assessment of the Diagnostic Delay in Japanese People with Parkinson's Disease Using a Web-based Survey of Patients and Physicians

Objective Although diagnostic criteria of Parkinson's disease (PD) have been established, the details of the process by which patients notice symptoms, visit a physician, and receive a diagnosis of PD is unclear. We therefore explored factors influencing latency in diagnosing PD. Methods We performed an internet-based survey of patients with PD and their families as well as physicians treating patients with PD to identify any diagnostic latency and its determinants. Evaluated factors included motor and non-motor symptoms, the diagnosis history and symptoms, patients' feelings toward PD prior to the diagnosis, and physician-determined reasons for the diagnostic delay. Results Among the 186 eligible patient respondents (including 87 responses from family members of patients), 24% received a PD diagnosis >1 year after the onset of PD-related symptoms, 58.6% had mid- or late-stage PD at the diagnosis, and 29% of patients had initially thought their symptoms were common age-related phenomena. Tremor (42%) was the most frequent symptom that led patients to visit a medical institution, whereas gait disturbance (14%) was the least frequent. More patients diagnosed with early-stage PD than those diagnosed with mid- or late-stage PD consulted a neurologist at their first visit. Among the 331 eligible physicians, patients' misinterpretation of their symptoms as being age-related was deemed one of or the most common cause (s) of a diagnostic delay by 67% and 36%, respectively. Conclusion Patients' insufficient or misinterpreted information about PD may cause delays in accessing healthcare services, leading to diagnostic delay.

A time-series analysis of blood-based biomarkers within a 25-year longitudinal dolphin cohort.

Causal interactions and correlations between clinically-relevant biomarkers are important to understand, both for informing potential medical interventions as well as predicting the likely health trajectory of any individual as they age. These interactions and correlations can be hard to establish in humans, due to the difficulties of routine sampling and controlling for individual differences (e.g., diet, socio-economic status, medication). Because bottlenose dolphins are long-lived mammals that exhibit several age-related phenomena similar to humans, we analyzed data from a well controlled 25-year longitudinal cohort of 144 dolphins. The data from this study has been reported on earlier, and consists of 44 clinically relevant biomarkers. This time-series data exhibits three starkly different influences: (A) directed interactions between biomarkers, (B) sources of biological variation that can either correlate or decorrelate different biomarkers, and (C) random observation-noise which combines measurement error and very rapid fluctuations in the dolphin's biomarkers. Importantly, the sources of biological variation (type-B) are large in magnitude, often comparable to the observation errors (type-C) and larger than the effect of the directed interactions (type-A). Attempting to recover the type-A interactions without accounting for the type-B and type-C variation can result in an abundance of false-positives and false-negatives. Using a generalized regression which fits the longitudinal data with a linear model accounting for all three influences, we demonstrate that the dolphins exhibit many significant directed interactions (type-A), as well as strong correlated variation (type-B), between several pairs of biomarkers. Moreover, many of these interactions are associated with advanced age, suggesting that these interactions can be monitored and/or targeted to predict and potentially affect aging.

WHAT ARE WE MISSING? Problems with using generational cohorts in leadership research and suggestions for a better direction.

The rising costs of recruiting and hiring workers and the seismic shift of age demographics in the United States workforce has created much stir around the concept of generational cohorts. Although much has been done by researchers and practitioners alike to attempt a better understanding of each generational group’s leadership preferences, confusing and contradictory results has attracted much criticism. This critique has inspired efforts to look at the concept of leadership and followership preference through an alternative lifespan developmental lens. Because leadership influences are inherently social influences, a person’s overall lifespan development level may potentially provide a deeper perspicacity of the phenomenon than examining it from the more conventional generational cohort perspective. However, specific research into this area is lacking. This paper adds to the literature by uncovering what we are missing in research and practice when we look at age-related leadership phenomena solely from a generational cohort perspective. A review of the contradicting literature on generational cohorts and leadership is offered. Next, specific lifespan developmental theories are examined, and propositions and implications of such research are extended.

Ageist Attitudes, Stereotypes and Behavior of Youth Towards the Elderly Within Georgia: How Significant are Intergenerational Contact and Perceived Distance?

Georgia has an aging society, with a high percentage of senior citizens in the general population. However, only small number of research studies in the Georgian context have been conducted to ascertain young people's attitudes towards older adults. The study of age-related phenomena is important both from a scientific point of view and for developing awareness-raising interventions and social policy. The current study investigates young people's explicit and implicit ageist attitudes, stereotypes and behaviors towards the elderly. We consider whether perceived distance from older people and intergenerational contact exert an influence on these variables. The research instruments were first translated from English into Georgian and adapted to the local context using 150 young people as initial respondents. The survey research was then carried out with 450 respondents, employing convenience sampling in Tbilisi. Research has shown that young people express more positive than negative explicit attitudes toward the elderly while implicit measures also reveal ingrained negative attitudes. Most stereotypes about older people feature lower expectations regarding physical and mental health, but especially concerning cognitive function. Young people stereotypically perceive older people as warm and kind, but with limited cognitive capacity. These stereotypes are more relevant to the “pity’ category identified in the Stereotype Content Model (SCM) representing a ‘pseudo-positive’ attitude toward older people and they tend to result in infantilizing behavior, i.e., not letting aged people take responsibility for their own lives. With increased perceived distance from older people, the frequency of intergenerational contact decreases. Similarly, younger people who harbor more robust explicit ageist attitudes toward older people frequently seek to increase perceived distance and minimize their contact with the elderly. More ageist attitudes are related to more ageist behaviours. Regression analysis shows that explicit attitudes have the strongest influence on ageist behavior followed by perceived distance, intergenerational contact and stereotypes. The current study can provide a basis for further research on this concept.

Sex Differences of Sarcopenia in an Elderly Asian Population: The Prevalence and Risk Factors.

The loss of muscle mass is widespread in age-related health phenomena in the elderly population. This study examined the prevalence of sarcopenia in a community-dwelling elderly population according to gender. The study also identified gender-specific risk factors in older people aged 75–84 years old. One thousand two hundred and ninety-three participants aged between 75 and 84 years from the National Health and Nutrition Examination Surveys in Korea were investigated. The prevalence of sarcopenia in males and females in the weighted-value sample was 41.2% (95%CI: 35.8–46.8) and 37.2% (32.7–41.9), respectively. Gender-specific clinical risk factors in males were height, weight, body mass index, waist circumference, skeletal muscle mass index, fasting glucose, and triglyceride levels. Height, weight, body mass index, waist circumference, skeletal muscle mass index, and total cholesterols were clinical risk factors for females. These outcomes would be crucial to primary care clinicians and health care professionals when patients require a referral for early detection and treatment. Health care professionals and clinicians can quickly identify potential sarcopenic patients by acknowledging the gender-specific prevalence and risk factors.

Prediction of Li-Ion Battery Discharge Patterns in IoT Devices Under Random Use Via Machine Learning Algorithms

Abstract This study presents foreseeing of the Lithium-ion battery discharge models for the Internet of Things (IoT) devices under randomized use patterns. IoT systems run in harmony with the human–machine interface, communication protocols and sharing data so long as uninterrupted data communication is exploited for their devices. Hence, forecasting the battery discharge duration is a very important issue for the regularization of IoT device performances. The well-known discharge duration is generally about the age-related electrochemical phenomena of an electrochemistry for Lithium-ion battery. The discharge changes of the battery were obtained from the input–output dynamics of the random battery use obtained from the randomized battery usage dataset in the NASA Ames prognostics data repository. They were investigated by machine learning methods and their results were estimated for life expectancy regularization of the IoT devices. In order to find the appropriate models of battery usage under randomized patterns, artificial neural network (ANN), Gaussian process and nonlinear regression models are evaluated in terms of battery capacity and internal resistance change as a function of discharged energy. The ${R}^2$, Adjusted ${R}^2$, root-mean-square-error (RMSE) and normalized-mean-square-error (NMSE) criteria were used to compare the performances of the obtained models for different settings. According to the results, ANN model, with settings of radial basis function activation function within single hidden-layer, and 20 hidden-layer neurons, shows the best performance in terms of ${R}^2=1.0000$ and $\mathrm{NMSE}={\mathrm{1.7384.10}}^{-4}$ metrics. $\mathrm{RMSE}={\mathrm{0.9896.10}}^{-4}$ is achieved by the ANN model with the settings of single hidden-layer with 10 neurons and hyperbolic-tangent activation function.

Age-related focal thinning of the ganglion cell-inner plexiform layer in a healthy population.

Given the aging of the population worldwide, to learn the underlying age-related biological phenomena is important to improve the understanding of the ageing process. Neurodegeneration is an age-associated progressive deterioration of the neuron. Retinal neurodegeneration during aging, such as the reduction in thickness of the retinal nerve fiber layer (RNFL) and ganglion cell-inner plexiform layer (GCIPL) measured by optical coherence tomography (OCT), has been reported, but no studies have provided their specific alteration patterns with age. Therefore, this study is to provide visualization of the evolution of various tomographic intraretinal layer thicknesses during aging and to document age-related changes in focal thickness. A total 194 healthy subjects were included in this cross-sectional study. The subjects were divided into four age groups: G1, <35 years; G2, 35-49 years; G3, 50-64 years; and G4 ≥65 years. One eye of each subject was imaged using a custom-built ultrahigh-resolution optical coherence tomography (UHR-OCT). Volumetric data centered on the fovea were segmented to obtain the thickness maps of six intraretinal layers, including the macular retinal nerve fiber layer (mRNFL) and GCIPL. There were alterations visualized in thickness maps in these intraretinal layers. The GCIPL showed a thickness reduction localized in the inner annulus in elder subjects (G4). Within the inner annulus, the most profound alteration in G4, an oval zone (length 0.76 mm and width 0.52 mm), appeared to be in the inferior sector about 0.61 mm below the fovea, named "A zone". The average thickness reduction of the A zone was 14.4 µm in the elderly group (G4). Age was significantly related to the GCIPL thickness of the inner annulus (ρ =-0.48; P<0.001) and of the A zone (ρ =-0.39, P<0.001). This is the first study to apply UHR-OCT for visualizing the age-related alteration of intraretinal layers in a general population. The most profound change of the optic nerve fiber is an oval-like focal thinning in GCIPL, which occurred in the inferior sector within the inner annulus and was strongly related to increased age.

Somatic comorbidity and physical frailty in elderly with medically unexplained symptoms

IntroductionReported prevalence rates of medically unexplained symptoms (MUS) in people aged ≥65 years range between 1.5 and 18%. People with MUS often describe a low quality of life and frequently suffer from co-morbid anxiety and depressive disorders. In our pilot study on older patients with MUS, the level of somatic comorbidity as well as frailty parameters were significantly higher among patients with MUS which was partially explained by a somatic origin compared to patients with MUS for which no explanation at all was found.ObjectivesThe objective of this study was to examine the level of frailty and somatic comorbidity in older patients with medically unexplained symptoms (MUS) and compare this to patients with medically explained symptoms (MES).MethodsFrailty was assessed according to Fried’s criteria (gait speed, handgrip strength, unintentional weight loss, exhaustion, and low physical activity), somatic comorbidity according to the self-report Charlson Comorbidity Index and the number of prescribed medications.ResultsAlthough MUS-patients had less physical comorbidity compared to MES-patients, they were prescribed the same number of medications. Moreover, MUS-patients were more often frail compared to MES-patients. Among MUS-patients, physical frailty was associated with the severity of unexplained symptoms, the level of hypochondriacal beliefs, and the level of somatisation.ConclusionsDespite a lower prevalence of overt somatic diseases, MUS-patients are more frail compared to older MES-patients. These results suggest that at least in some patients age-related phenomena might be erroneously classified as MUS, which may affect treatment strategy.DisclosureNo significant relationships.

Shifts in Gait Signatures Mark the End of Lifespan in Mice, With Sex Differences in Timing.

Reduced walking speed is a hallmark of functional decline in aging across species. An age-related change in walking style may represent an additional key marker signifying deterioration of the nervous system. Due to the speed dependence of gait metrics combined with slowing of gait during aging, it has been challenging to determine whether changes in gait metrics represent a change in style. In this longitudinal study we employed gait signatures to separate changes in walking style and speed in mice. We compared gait signatures at mature adult age with middle aged, old and geriatric time points and included female and male sub-cohorts to examine sex differences in nature or timing signature shifts. To determine whether gait signature shifts occurred independently from a decline in other mobility domains we measured balance and locomotor activity. We found that walking speed declined early, whereas gait signatures shifted very late during the aging process. Shifts represented longer swing time and stride length than expected for speed, as in slow motion, and were preceded by a decline in other mobility domains. The pattern of shifts was similar between female and male cohorts, but with sex differences in timing. We conclude that changes in walking style, speed and other mobility domains represent separate age-related phenomena. These findings call for careful, sex specific selection of type and timing of outcome measures in mechanistic or interventional studies. The pattern of age-related gait signature shifts is distinct from patterns seen in neurodegenerative conditions and may be a translatable marker for the end of the lifespan.

Renal disease associated with myeloproliferative neoplasms and myelodysplastic syndrome/myeloproliferative neoplasms.

Renal changes in patients with myeloproliferative neoplasms (MPNs) or myelodysplastic syndrome (MDS)/MPNs have been addressed by few, respectively no, reports. The aim of this study was to focus on a systematic evaluation of renal biopsies in patients with MPNs or MDS/MPNs. The cohort comprised 29 patients (23 men) aged 67±11years (mean±standard deviation), diagnosed with chronic myeloid leukaemia (n=5), polycythaemia vera (n=9), primary myelofibrosis (n=5), essential thrombocythaemia (n=2), or chronic myelomonocytic leukaemia (n=4), as well as MPNs or MDS/MPNs not otherwise specified (n=4). Patients manifested with proteinuria (93%), partially in the nephrotic range (46%), haematuria (72%), and impaired kidney function (93%). The most prominent histological findings included double-contoured glomerular basement membranes (71%), acute endothelial damage (68%), intracapillary platelet aggregation (62%), mesangiolysis (21%), thrombotic microangiopathy (24%), segmental glomerulosclerosis (66%), mesangial hypercellularity and sclerosis, extramedullary haematopoiesis (17%), and also IgA nephropathy (21%) and glomerulonephritis (GN) with features of infection-related GN (21%). MPN and MDS/MPN patients showed significantly more chronic changes than age-matched and sex-matched controls, including global and segmental glomerulosclerosis, mesangial sclerosis, and hypercellularity, whereas the extent of arteriosclerosis was comparable. MPN and MDS/MPN patients show glomerular scarring that exceeds age-related phenomena. Ongoing endothelial damage, growth factors released by platelets and deposition of immune complexes are probably the causative mechanisms. Early recognition of renal failure heralded by proteinuria and haematuria, and consequent control of risk factors for kidney failure, should be recommended for MPN and MDS/MPN patients.

Extract of Plumbago zeylanica enhances the growth of hair follicle dermal papilla cells with down-regulation of 5α-reductase type II.

Cellular senescence, a phenomenon of irreversible growth arrest of mammalian cells, is involved in various age-related phenomena in organisms. Hair follicle dermal papilla (DP) cells play important roles in the regulation of hair growth and loss. We examined the implication of cellular senescence of DP cells in androgenetic alopecia (AGA), the most common form of male hair loss, and searched for the compounds that have a beneficial effect on the prevention of AGA. Expression of the 5α-reductase type II (SRD5A2) gene, which plays a key role in the development of AGA, was examined by quantitative RT-PCR and Western blotting analysis in DP cells. Besides, DP cells were cultured with the extracts of herbs used in traditional Ayurvedic medicine to search for the compounds that have a beneficial effect on the growth of DP cells. We found that expression of the SRD5A2 was up-regulated in senescent DP cells. We also found that the herbal extract of Plumbago zeylanica (root) enhanced the growth of DP cells and down-regulated the expression of SRD5A2 in DP cells. Further, plumbagin, an ingredient of Pzeylanica, would be responsible for the above effects of Pzeylanica. These results suggested the possibility that senescent DP cells may have a role in the development of AGA through up-regulating SRD5A2 expression, and the Pzeylanica extract and plumbagin may suppress its development through enhancing the growth of DP cells and down-regulating SRD5A2 expression in DP cells.

Age-related rhesus macaque models of COVID-19.

BackgroundSince December 2019, an outbreak of the Corona Virus disease 2019 (COVID‐19) caused by severe acute respiratory syndrome coronavirus (SARS‐CoV‐2) in Wuhan, China, has become a public health emergency of international concern. The high fatality of aged cases caused by SARS‐CoV‐2 was a need to explore the possible age‐related phenomena with non‐human primate models.MethodsThree 3‐5 years old and two 15 years old rhesus macaques were intratracheally infected with SARS‐CoV‐2, and then analyzed by clinical signs, viral replication, chest X‐ray, histopathological changes and immune response.ResultsViral replication of nasopharyngeal swabs, anal swabs and lung in old monkeys was more active than that in young monkeys for 14 days after SARS‐CoV‐2 challenge. Monkeys developed typical interstitial pneumonia characterized by thickened alveolar septum accompanied with inflammation and edema, notably, old monkeys exhibited diffuse severe interstitial pneumonia. Viral antigens were detected mainly in alveolar epithelial cells and macrophages.ConclusionSARS‐CoV‐2 caused more severe interstitial pneumonia in old monkeys than that in young monkeys. Rhesus macaque models infected with SARS‐CoV‐2 provided insight into the pathogenic mechanism and facilitated the development of vaccines and therapeutics against SARS‐CoV‐2 infection.

Senoinflammation: A major mediator underlying age-related metabolic dysregulation.

Chronic inflammation is a complex and unresolved inflammatory response with low-grade multivariable patterns that aggravate systemic pathophysiological conditions and the aging process. To redefine and delineate these age-related complex inflammatory phenomena at the molecular, cellular, and systemic levels, the concept of "Senoinflammation" was recently formulated. In this review, we describe the accumulated data on both the multiphase systemic inflammatory process and the cellular proinflammatory signaling pathway. We also describe the proinflammatory mechanisms underlying the metabolic molecular pathways in aging. Additionally, we review age-related lipid accumulation, the role of the inflammatory senescence-associated secretory phenotype (SASP), the involvement of cytokine/chemokine secretion, endoplasmic reticulum (ER) stress, insulin resistance, and autophagy. The last section of the review highlights the modulation of the senoinflammatory process by the anti-aging and anti-inflammatory action of calorie restriction (CR). Evidence from aging and CR research strongly suggests that SASP from senescent cells may be the major source of secreted cytokines and chemokines during aging. A better understanding of the mechanisms underpinning the senoinflammatory response and the mitigating role of CR will provide insights into the molecular mechanisms of chronic inflammation and aging for potential interventions.

How age and surface inclination affect joint moment strategies to accelerate and decelerate individual leg joints during walking

A joint moment also causes motion at other joints of the body. This joint coupling-perspective allows more insight into two age-related phenomena during gait. First, whether increased hip kinetic output compensates for decreased ankle kinetic output during positive joint work. Second, whether preserved joint kinetic patterns during negative joint work in older age have any functional implication. Therefore, we examined how age and surface inclination affect joint moment strategies to accelerate and/or decelerate individual leg joints during walking. Healthy young (age: 22.5 ± 4.1 years, n = 18) and older (age: 76.0 ± 5.7 years, n = 22) adults walked at 1.4 m/s on a split-belt instrumented treadmill at three grades (0%, 10%, −10%). Lower-extremity moment-induced angular accelerations were calculated for the hip (0% and 10%) and knee (0% and −10%) joints. During level and uphill walking, both age groups showed comparable ankle moment-induced ipsilateral (p = 0.774) and contralateral (p = 0.047) hip accelerations, although older adults generated lower ankle moments in late stance. However, ankle moment-induced contralateral hip accelerations were smaller (p = 0.001) in an older adult subgroup (n = 13) who showed larger hip extension moments in early stance than young adults. During level and downhill walking, leg joint moment-induced knee accelerations were unaffected by age (all p > 0.05). These findings suggest that during level and uphill walking increased hip flexor mechanical output in older adults does not arise from reduced ankle moments, contrary to increased hip extensor mechanical output. Additionally, results during level and downhill walking imply that preserved eccentric knee extensor function is important in maintaining knee stabilization in older age.

Frailty and Somatic Comorbidity in Older Patients With Medically Unexplained Symptoms

ObjectivesTo examine the level of frailty and somatic comorbidity in older patients with medically unexplained symptoms (MUS) and compare this to patients with medically explained symptoms (MES). DesignCross-sectional, comparative study. SettingCommunity, primary care, and secondary healthcare to recruit patients with MUS in various developmental and severity stages and primary care to recruit patients with MES. ParticipantsIn total, 118 patients with MUS and 154 patients with MES, all aged ≥60 years. MethodsFrailty was assessed according to the Fried criteria (gait speed, handgrip strength, unintentional weight loss, exhaustion, and low physical activity), somatic comorbidity according to the self-report Charlson comorbidity index, and the number of prescribed medications. ResultsAlthough patients with MUS had less physical comorbidity compared with patients with MES, they were prescribed the same number of medications. Moreover, patients with MUS were more often frail compared with patients with MES. Among patients with MUS, physical frailty was associated with the severity of unexplained symptoms, the level of hypochondriacal beliefs, and the level of somatisation. Conclusions and implicationsDespite a lower prevalence of overt somatic diseases, patients with MUS are more frail compared with older patients with MES. These results suggest that at least in some patients age-related phenomena might be erroneously classified as MUS, which may affect treatment strategy.

Chapter 26 - Clinical neurophysiology of NREM parasomnias

The nonrapid eye movement (NREM) parasomnias range from age-related developmental phenomena in children to aggressive and injurious motor behaviors in all age groups. These parasomnias are commonly referred to as disorders of arousal and are an important cause of sleep-related injury. Genetic predisposition plays a role in the disorders of arousal, most evident in sleepwalking. Important concepts guiding our current understanding of the pathophysiology of the NREM parasomnias include sleep state instability (a propensity for arousal during NREM sleep), sleep inertia (incomplete awakening from NREM sleep), state dissociation (an ability to simultaneously straddle both NREM sleep and wakefulness), and activation of central pattern generators (permitting expression of subcortically determined motor behaviors without conscious higher cortical input). Management is multifaceted with an emphasis on education and nonpharmacologic measures. The purpose of this chapter is to review wake and NREM neurobiology and update our current understanding of NREM parasomnia pathophysiology, epidemiology, genetics, clinical features, precipitating factors, neurophysiologic evaluation, diagnosis, and clinical management.