Aging Population Research Articles

Health care expenditure, economic growth, and population ageing in Japan: empirical evidence using the nonlinear ARDL approach

ABSTRACT In Japan, health care expenditure (HCE) has increased with the rapid ageing of the population. It raises concerns on how the public health care insurance system should be sustained in the future, since the dependence on public burdens is growing under the government’s difficult financial conditions. This study investigates the cointegration relationship between HCE, GDP, and the population ageing rate (AGE) in Japan for the period 1960–2019 by using the nonlinear ARDL approach. The results revealed that per capita HCE may increase more significantly during an economic downturn than during an economic improvement in the long-run. Moreover, an increase in AGE has a positive effect on per capita HCE. These findings show the need to achieve stable economic growth and seriously address the issue of ageing for policymakers in Japan.

Adaptations of the work environment facilitating the professional activity of seniors

Analysis of demographic trends indicates that there is an increasing proportion of people who can be described as elderly. In Poland, the population aged >60 years is expected to increase to 10.8 million in 2030 and to 13.7 million in 2050, i.e., around 40% of total population. In line with the general trend, the issue of the aging of the professionally active population is becoming more relevant. The average age of the world's working population is steadily increasing. In the European Union, workers aged 55-64 years accounted for 50% of the total workforce in 2013, and already 59% in 2018. In Poland, in 2018, people aged 55-64 years accounted for 49% of the employed population. The low percentage of people working at this age is due, among other things, to employers' attitudes towards employing older people, perceiving them as employees who are more difficult to manage and have health problems. Moreover, working conditions of seniors are not adapted to their age capabilities. It is necessary to reduce the burden of physical work, especially in awkward positions, carrying loads, monotonous work and piecework. It is important to create work organization in which it is possible to refer to the experience of older people, who should have freedom of action, without time pressure and the need to perform many tasks at the same time. The ever-increasing social dependence on information technology tools creates new problems for seniors. Taking into account age-related difficulties in acquiring new knowledge, it is important to provide them with simplified tools that are easier to use. The scope of necessary actions to enable the aging population to work is very wide, ranging from legislative, technological and organizational changes, ending with education addressed both to people responsible for employee safety (including occupational health services) and to current and potential employees. Med Pr Work Health Saf. 2024;75(3).

Promoting active mobility in old age through urban design

In an ageing society, maintaining independent mobility into old age is an important objective. Mental and physical wellbeing depends not only on individual health status, but also to alarge extent on the spatial conditions. Local politics and municipal administrations can influence this, especially in urban planning. This discussion article brings together perspectives from public health and urban planning on urban development and mobility against the background of health equity.The results of the AFOOT (Securing urban mobility of an ageing population) cross-sectional study on socio-spatial conditions in small- and medium-sized towns in northwestern Germany and walking and cycling by older people show the importance of residential environmental factors such as proximity to everyday destinations, walking and cycling infrastructure, and street connectivity. Preferences for the design of an age-friendly living environment and the quality of public spaces exist in terms of urban design quality, quality of stay, and safety in public spaces.In order to improve spatial conditions, the situation needs to be recorded using defined indicators and monitoring, and the perspectives of older people need to be integrated. Strategies and measures to promote active mobility in old age are aimed at the multifunctional design of public spaces, the prioritization of active mobility on everyday trips, and ensuring the accessibility of everyday destinations through urban development. Cross-sectoral cooperation between urban planning, transport planning, and public health is essential to promote the active mobility and health of older people.

Labor market trends and the need for reengineering higher education

The dynamics of the labor market have changed considerably and are currently experiencing a major shift. The skill levels that used to be enough in the workplace have become inadequate for the current workplace requirements. At least in the case of the United States, the kind of jobs that allowed work from home during the pandemic typically required college education; this may be a silver lining for colleges. Coupled with this, the admission test optional policies opened the doors of colleges for many otherwise disadvantaged students. The life cycle duration of technical skills has become shorter than ever before. Issues in innovation, demographic shifts, socio-cultural issues, aging population and technological advances are driving educators, employers, and policy makers to re-examine higher education to address the skill gaps currently existing in the workplace. This paper brainstorms some of these topics and propose solutions for policy makers.

Associations of hypertension, diabetes and heart disease risk with body mass index in older Chinese adults: a population-based cohort study

ObjectiveObesity is a well-established risk factor for disease. Controversy exists regarding the relative risk of morbidity and mortality in individuals who are overweight or underweight compared with individuals with a...

Multimorbidity, health Literacy, and quality of life among older adults in an urban slum in India: a community-based cross-sectional study

BackgroundIndia is experiencing a rising burden of chronic disease multimorbidity due to an aging population and epidemiological transition. Older adults residing in urban slums are especially vulnerable due to challenges in managing multimorbidity amid deprived living conditions. This study aimed to assess the prevalence of multimorbidity, associated health literacy, and quality of life impact in this population.MethodsA community-based cross-sectional study was conducted among 800 adults aged ≥ 65 years in an urban slum in Gujarat, India. Data on sociodemographics, physical and mental health conditions, health literacy (HLS-SF-47), quality of life (Short Form-12 scale), and social determinants of health were collected. Multimorbidity is ≥ 2 physical or mental health conditions in one person.ResultsThe prevalence of multimorbidity was 62.5% (500/800). Multimorbidity was significantly associated with lower physical component summary (PCS) and mental component summary (MCS) scores on the SF-12 (p < 0.001). After adjusting for sociodemographic variables, the odds ratio of 0.81 indicates that for every 1 unit increase in the health literacy score, the odds of having multimorbidity decrease by 19%. Older age within the older adult cohort (per year increase) was associated with greater odds of multimorbidity (AOR 1.05, 95% CI 1.02–1.09). Physical inactivity (AOR 1.68, 95% CI 1.027–2.77) and lack of social support (AOR 1.57, 95% CI 1.01–2.45) also increased the likelihood of multimorbidity.ConclusionThere is a substantial burden of multimorbidity among urban slum dwellers aged ≥ 65 years in India, strongly linked to modifiable risk factors like poor health literacy and social determinants of health. Targeted interventions are essential to alleviate this disproportionate burden among urban slum older adults.

Treatment of chronic kidney disease in older populations.

As the world population ages, an expected increase in the prevalence of chronic kidney disease (CKD) among older individuals will pose a considerable challenge for health care systems in terms of resource allocation for disease management. Treatment strategies for older patients with CKD should ideally align with those applied to the general population, focusing on minimizing cardiovascular events and reducing the risk of progression to kidney failure. Emerging therapies, such as SGLT-2 inhibitors and GLP-1 receptor agonists, hold promise for the effective management of CKD in older individuals. In addition, non-pharmacological interventions such as nutritional and exercise therapies have a crucial role. These interventions enhance the effects of pharmacotherapy and, importantly, contribute to the maintenance of cognitive function and overall quality of life. Various factors beyond age and cognitive function must be taken into account when considering kidney replacement therapy for patients with kidney failure. Importantly, all treatment options, including dialysis, transplantation and conservative management approaches, should be tailored to the individual through patient-centred decision-making. The dynamic integration of digital technologies into medical practice has the potential to transform the management of CKD in the aging population.

Personalized starting age of gastric cancer screening based on individuals' risk profiles: a population-based prospective study.

The current recommended starting age for gastric cancer (GC) lacks unified guideline and individualized criteria. We aimed to determine risk-stratified starting age for GC screening in China based on individuals' risk profiles, and develop an online calculator for clinical application. In this multi-center population-based prospective study, we divided participants enrolled during 2015-2017 (n = 59,771, aged 40-69) into screened and unscreened groups and observed them for primary endpoints-GC occurrence, all-cause and GC-specific deaths. The median follow-up was 6.07 years. To determine the reference starting age, the effectiveness of GC screening was assessed by age-groups after propensity-score-matching. Further, we categorized the calculated individual risk scores (using well-established risk factors) by quantiles. Subsequently, we used age-specific 10-year cumulative risk curves to estimate the risk-stratified starting age-when the individual's risk level matches reference starting age risk threshold. During follow-up, 475 GC cases, 182 GC deaths and 1,860 all-cause deaths occurred. All-cause and GC-specific mortality decreased among screened individuals aged ≥45 and 50-59 years, respectively. Thus, the average population (reference) starting age was set as 50 years. The 10-year cumulative risk of GC in average population aged 50 was 1.147%. We stratified the starting age using eight risk factors, and categorized participants as low-, medium-, and high-risk individuals, whose risk-stratified starting age was 58, 50, and 46, respectively. While high-risk individuals warrant 3-5 years earlier GC screening than average population (age 50), low-risk individuals can tolerate delayed screening. Our online, personalized starting-age calculator will help risk-adapted GC screening (https://web.consultech.com.cn/gastric/#/).

The relation between MIND diet with odds of attention-deficit/hyperactivity disorder in Iranian children: a case-control study

ABSTRACT This study aims to investigate the association between the MIND index (Mediterranean- Dietary approaches to Stop Hypertension diet Intervention for Neurodegenerative Delay) and attention-deficit hyperactivity disorder (ADHD) in the Iranian children. It builds upon existing research that highlights the role of dietary antioxidants in alleviating psychological disorders, cognitive impairments, and memory deficits. Additionally, previous studies have separately explored the beneficial effects of the Mediterranean and DASH diets on these issues. A case-control study was undertaken in Iran, involving a sample of 360 children and adolescents aged 7–13 years. Participants were divided into two groups, namely the case group (n = 120) and the control group (n = 240), with age and sex being matched between the groups. The Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV-TR) was employed for the diagnosis of ADHD. The MIND diet score was computed using the food intake data acquired from the Food Frequency Questionnaire (FFQ) completed by the subjects. The mean ± SD for the age and BMI of the study population was 8.76 ± 1.64 years and 16.90 ± 3.58 kg/m2, respectively. The mean score of MIND in this study was 27.93. After adjustment for potential confounder in the final model, subjects in highest compared to the lowest quartile of MIND diet score had significantly lower odds of ADHD (OR = 0.59, 95% CI 0.37–0.83; P-trend = 0.019). This study provides valuable evidence suggesting that adherence to the MIND diet is associated with decreased odds of ADHD.

Social Participation and Loneliness in Older Adults in a Rural Australian Context: Individual and Organizational Perspectives

A rise in aging populations globally calls attention to factors that influence the well-being and health of older adults, including social participation. In Australia, rural older adults face cultural, social, and physical challenges that place them at risk for isolation. Thus, research surrounding social participation and healthy aging is increasingly relevant, especially in rural areas. This qualitative study in a remote town in Western Australia explores barriers and facilitators to older adults’ social participation. To investigate multiple perspectives, 23 adults aged 50+ and 19 organizations from a rural town were interviewed. A stakeholder reference group was engaged to refine the research design and validate the findings. Feedback from early interviews was used to refine the data collection process, thus enhancing the validity of the findings. Thematic analysis showed that health and mobility issues, inadequate infrastructure, poor sustainability, and cultural tensions commonly impacted social participation. Themes of rural town culture, cultural power dynamics, and rural stoicism were identified as cultural aspects that inhibited participation. Based on results of this study and the supporting literature, recommendations for inclusive activities include supporting community-designed programs, utilizing culturally sensitive language and personnel, expanding services using existing community resources, and diversifying older adults’ roles in existing groups.

Impact of SGLT2 Inhibitors on Very Elderly Population with Heart Failure with Reduce Ejection Fraction: Real Life Data

(1) Background: The validation of new lines of therapy for the elderly is required due to the progressive ageing of the world population and scarce evidence in elderly patients with HF with reduced ejection fraction (HFrEF). The purpose of our study is to analyze the effect of SGLT2 inhibitors (SGLT2i) in this subgroup of patients. (2) Methods: A single-center, real-world observational study was performed. We consecutively enrolled all patients aged ≥ 75 years diagnosed with HFrEF and for treatment with SGLT2i, and considered the theoretical indications. (3) Results: A total of 364 patients were recruited, with a mean age of 84.1 years. At inclusion, the mean LVEF was 29.8%. Median follow-up was 33 months, and there were 122 deaths. A total of 55 patients were under SGLT2i treatment. A multivariate Cox logistic regression test for all-cause mortality was performed, and only SGLT2i (HR 0.39 [0.19–0.82]) and glomerular filtration rate (HR 0.98 [0.98–0.99]) proved to be protective factors. In parallel, we conducted a propensity-score-matched analysis, where a significant reduction in all-cause mortality was associated with the use of SGLT2i treatment (HR 0.39, [0.16–0.97]). (4) Conclusions: Treatment with SGLT2i in elderly patients with HFrEF was associated with a lower rate of all-cause mortality. Our data show that SGLT2i therapy could improve prognosis in the elderly with HFrEF in a real-world study.

Implementation and evaluation of a system for assessment of the quality of long-term management of patients at a geriatric hospital

BackgroundThe increasing aging population presents a significant challenge, accompanied by a shortage of professional caregivers, adding to the therapeutic burden. Clinical decision support systems, utilizing computerized clinical guidelines, can improve healthcare quality, reduce expenses, save time, and boost caregiver efficiency. Objectives1) Develop and evaluate an automated quality assessment (QA) system for retrospective longitudinal care quality analysis, focusing on clinical staff adherence to evidence-based guidelines (GLs). 2) Assess the system’s technical feasibility and functional capability for senior nurse use in geriatric pressure-ulcer management. MethodsA computational QA system using our Quality Assessment Temporal Patterns (QATP) methodology was designed and implemented. Our methodology transforms the GL’s procedural-knowledge into declarative-knowledge temporal-abstraction patterns representing the expected execution trace in the patient’s data for correct therapy application. Fuzzy temporal logic allows for partial compliance, reflecting individual and grouped action performance considering their values and temporal aspects. The system was tested using a pressure ulcer treatment GL and data from 100 geriatric patients’ Electronic Medical Records (EMR). After technical evaluation for accuracy and feasibility, an extensive functional evaluation was conducted by an experienced nurse, comparing QA scores with and without system support, and versus automated system scores. Time efficiency was also measured. ResultsQA scores from the geriatric nurse, with and without system’s support, did not significantly differ from those provided by the automated system (p < 0.05), demonstrating the effectiveness and reliability of both manual and automated methods. The system-supported manual QA process reduced scoring time by approximately two-thirds, from an average of 17.3 min per patient manually to about 5.9 min with the system’s assistance, highlighting the system’s efficiency potential in clinical practice. ConclusionThe QA system based on QATP, produces scores consistent with an experienced nurse’s assessment for complex care over extended periods. It enables quick and accurate quality care evaluation for multiple patients after brief training. Such automated QA systems may empower nursing staff, enabling them to manage more patients, accurately and consistently, while reducing costs due to saved time and effort, and enhanced compliance with evidence-based guidelines.

The effects of time restricted feeding on age-related changes in the mouse retina

Dietary modifications such as caloric restriction (CR) and intermittent fasting (IF) have gained popularity due to their proven health benefits in aged populations. In time restricted feeding (TRF), a form of intermittent fasting, the amount of time for food intake is regulated without restricting the caloric intake. TRF is beneficial for the central nervous system to support brain health in the context of aging. Therefore, we here ask whether TRF also exerts beneficial effects in the aged retina. We compared aged mice (24 months) on a TRF paradigm (access to food for six hours per day) for either 6 or 12 months against young control mice (8 months) and aged control mice on an ad libitum diet. We examined changes in the retina at the functional (electroretinography), structural (histology and fluorescein angiograms) and molecular (gene expression) level. TRF treatment showed amelioration of age-related reductions in both scotopic and photopic b-wave amplitudes suggesting benefits for retinal interneuron signaling. TRF did not affect age-related signs of retinal inflammation or microglial activation at either the molecular or histological level. Our data indicate that TRF helps preserve some aspects of retinal function that are decreased with aging, adding to our understanding of the health benefits that altered feeding patterns may confer.

Assessing osteoporosis screening compliance in total joint surgery: a retrospective chart review.

Osteoporosis is a prevalent concern, particularly among aging populations, leading to increased risk of fractures, including those related to hip and knee arthroplasty procedures. Screening for osteoporosis, especially with dual X-ray absorptiometry (DXA) scans, is crucial for early detection and management. This study aimed to assess adherence to osteoporosis screening guidelines among patients aged 65 and older undergoing elective total hip arthroplasty (THA) or total knee arthroplasty (TKA) within a single health network. Factors influencing screening adherence were also explored. A retrospective chart review of 2,160 patients undergoing elective THA or TKA between January 2019 and January 2023 was conducted. Demographic data, osteoporosis screening status, and occurrence of periprosthetic fractures were analyzed. Statistical analysis included descriptive statistics and chi-square tests. Only 24.1 % of eligible patients underwent a DXA scan prior to surgery. Females were more likely to undergo screening than males, and race was also associated with screening status. A total of 45 periprosthetic fractures were identified, with no significant correlation between osteoporosis status, DXA screening, and fracture occurrence. Adherence to osteoporosis screening guidelines among geriatric patients undergoing elective total joint arthroplasty remains low within the studied health network. Despite the lack of correlation between screening and fracture occurrence in this study, the importance of screening and potential optimization in high-risk patients is emphasized. Further research is needed to assess outcomes associated with different care pathways in bone health screening and management for elective geriatric total joint patients.

Bidirectional Relationships between Sarcopenia and Pelvic Floor Disorders

Sarcopenia and pelvic floor disorders (PFDs) are prevalent and often cooccurring conditions in the aging population. However, their bidirectional relationship and underlying mechanisms remain underexplored. This narrative review aims to elucidate this relationship by exploring potential causative interplays, shared pathophysiological mechanisms, and common risk factors. A comprehensive literature search was conducted to identify relevant studies focusing on epidemiological associations, interaction mechanisms, and implications for patient care. While epidemiological studies demonstrate associations between sarcopenia and PFDs, our findings reveal a cyclical relationship where sarcopenia may exacerbate PFDs through mechanisms such as decreased muscle strength and mobility. Conversely, the presence of PFDs often leads to reduced physical activity due to discomfort and mobility issues, which in turn exacerbate the muscle atrophy associated with sarcopenia. Additionally, shared risk factors such as physical inactivity, nutritional deficiencies, metabolic syndrome, and menopausal hormonal changes likely contribute to the onset and progression of both conditions. These interactions underscore the importance of concurrently integrated care approaches that address both conditions. Effective management requires comprehensive screening, the recognition of contributing factors, and tailored exercise regimens supported by a multidisciplinary approach. Future research should focus on longitudinal studies tracking disease progression and evaluating the efficacy of multidisciplinary care models in optimizing patient outcomes.

Capturing Home Care Information Management and Communication Processes Among Caregivers of Older Adults: Qualitative Study to Inform Technology Design.

The demand for complex home care is increasing with the growing aging population and the ongoing COVID-19 pandemic. Family and hired caregivers play a critical role in providing care for individuals with complex home care needs. However, there are significant gaps in research informing the design of complex home care technologies that consider the experiences of family and hired caregivers collectively. The objective of this study was to explore the health documentation and communication experiences of family and hired caregivers to inform the design and adoption of new technologies for complex home care. The research involved semistructured interviews with 15 caregivers, including family and hired caregivers, each of whom was caring for an older adult with complex medical needs in their home in Ontario, Canada. Due to COVID-19-related protection measures, the interviews were conducted via Teams (Microsoft Corp). The interview guide was informed by the cognitive work analysis framework, and the interview was conducted using storytelling principles of narrative medicine to enhance knowledge. Inductive thematic analysis was used to code the data and develop themes. Three main themes were developed. The first theme described how participants were continually updating the caregiver team, which captured how health information, including their communication motivations and intentions, was shared among family and hired caregiver participants. The subthemes included binder-based health documentation, digital health documentation, and communication practices beyond the binder. The second theme described how participants were learning to improve care and decision-making, which captured how they acted on information from various sources to provide care. The subthemes included developing expertise as a family caregiver and tailoring expertise as a hired caregiver. The third theme described how participants experienced conflicts within caregiver teams, which captured the different struggles arising from, and the causes of, breakdowns in communication and coordination between family and hired caregiver participants. The subthemes included 2-way communication and trusting the caregiver team. This study highlights the health information communication and coordination challenges and experiences that family and hired caregivers face in complex home care settings for older adults. Given the challenges of this work domain, there is an opportunity for appropriate digital technology design to improve complex home care. When designing complex home care technologies, it will be critical to include the overlapping and disparate perspectives of family and hired caregivers collectively providing home care for older adults with complex needs to support all caregivers in their vital roles.

A community-based geriatric interprofessional education experience and its impact on post-graduate collaborative practice

ABSTRACT While a growing body of interprofessional education (IPE) literature demonstrates a positive impact on learner knowledge, there is limited data on its long-term impact on collaborative practice (CP). With the growth of the aging population globally, understanding both the long-term impact on CP and sustainability of community-based geriatric experiential IPE programs are imperative. This study explores the impact of the Interprofessional Geriatric Curriculum (IPGC), a community-based geriatric IPE program, on post-graduate clinical practice among seven health professions. This study utilized a cross-sectional descriptive design, where both qualitative and quantitative data were collected in the same online survey of health professionals’ to measure their perceptions of the impact IPGC has had on their respective clinical practice 1–3 years post-graduation. Forty-six per cent of health profession graduates provided clinical care for people 65 years of age or older; 81% worked in interprofessional teams; 80% reported the IPGC experience significantly impacted their practice (N = 137), and all used validated assessment tools taught in the IPGC program in their practice. Eight themes emerged from the list of what health professionals learned from IPGC that they use regularly in their clinical practice: four themes were interprofessional in nature (i.e. teamwork and team-based care, interprofessional communication, roles/responsibilities, and personal/professional) and four themes related to geriatrics (i.e. aging, screening and assessment, medications, and didactic content). This study is one of the first to describe the sustained influence of a community-based IPE program across multiple health professional disciplines on clinical geriatric practice.

The global, regional, and national patterns of change in the burden of non-malignant upper gastrointestinal diseases from 1990 to 2019 and the forecast for the next decade.

Non-malignant upper gastrointestinal diseases, including peptic ulcer disease (PUD), gastritis and duodenitis (GD), and gastroesophageal reflux disease (GERD), significantly challenge global healthcare. These conditions not only impact patient health but also highlight socio-economic development issues and healthcare system accessibility and efficiency. Utilizing the Global Burden of Disease (GBD) database, this study aims to assess the global burden of PUD, GD, and GERD comprehensively, examining their association with the sociodemographic index (SDI). Employing data from the GBD 2019 database, this study analyzed the disability-adjusted life years (DALYs) for PUD, GD, and GERD. We integrated the SDI with the inequality slope index and concentration index for an international health inequality analysis, assessing disparities in the burden of these non-malignant upper gastrointestinal diseases. Decomposition analysis was conducted to determine the effects of population growth, aging, and epidemiological shifts on disease burden. Frontier analysis was performed to identify potential improvement areas and disparities among countries by development status. Disease time trends were depicted using a Joinpoint regression model, and the Bayesian age-period-cohort (BAPC) model projected the disease burden up to 2030. Between 1990 and 2019, the age-standardized DALYs rates (ASDR) for non-malignant upper gastrointestinal diseases declined. However, global geographic heterogeneity remained evident, closely linked to the SDI. Notably, low-SDI countries experienced higher disease burdens. Population growth and aging emerged as principal contributors to the increasing disease burden. Despite development levels, many countries have considerable potential for reducing the burden of these diseases. Furthermore, significant variations in the time trends of non-malignant upper gastrointestinal diseases were observed among countries and regions with different SDI levels, a pattern expected to continue through 2030. Non-malignant upper gastrointestinal diseases demonstrate notable heterogeneity across age, gender, and geography, with the disparities most marked in underdeveloped regions or countries. Consequently, it is imperative to focus research on policy development and to enact prevention and treatment strategies tailored to high-risk groups. This targeted approach is essential for mitigating the disease burden effectively.

Perception of defecation intent: applied methods and technology trends.

The aging population has led to a widening gap between the supply and demand for defecation care. To address this issue, the development of defecation care devices is the most direct and effective solution. Pre-defecation care devices offer a more personalized and comfortable alternative to the conventional post-defecation care devices currently available on the market. Furthermore, they facilitate greater patient involvement in the care process. Real-time monitoring and accurate identification of defecation intention are key technologies in the development of pre-defecation nursing devices. Automatic and accurate online monitoring of defecation intention can provide accurate early warning information fordifferentiated defecation assistance and cleansing care, effectively reducing nursing workload and improving patients' quality of life. However, there are relatively few studies on real-time monitoring and accurate identification of defecation intention. This review summarizes the existing defecation intention sensing technologies and their monitoring principles and research status, and explores the potential development direction of defecation intention sensing systems by comparing the characteristics and application conditions of various sensing technologies, which provides a direction for perception strategies for future defecation intention monitoring and earlywarning research.

Associations amongst dynamic knee stiffness during gait, quadriceps stiffness, and the incidence of knee osteoarthritis over 24 months: a cohort study with a mediation analysis

BackgroundDecreased strength and increased stiffness of the quadriceps have been associated with a higher risk of developing knee osteoarthritis (OA) in elders. Dynamic joint stiffness (DJS) represents collective resistance from active and passive knee structures for dynamic knee motions. Elevated sagittal knee DJS has been associated with worsening of cartilage loss in knee OA patients. Altered quadriceps properties may affect DJS, which could be a mediator for associations between quadriceps properties and knee OA. Hence, this study aimed to examine whether DJS and quadriceps properties would be associated with the development of clinical knee OA over 24 months, and to explore the mediation role of DJS in associations between quadriceps properties and knee OA.MethodsThis was a prospective cohort study with 162 healthy community-dwelling elders. Gait analysis was conducted to compute DJS during the loading response phase. Quadriceps strength and stiffness were evaluated using a Cybex dynamometer and shear-wave ultrasound elastography, respectively. Knee OA was defined based on clinical criteria 24 months later. Logistic regression with generalized estimating equations was used to examine the association between quadriceps properties and DJS and incident knee OA. Mediation analysis was performed to explore the mediation role of DJS in associations between quadriceps properties and the incidence of knee OA.ResultsA total of 125 participants (65.6 ± 4.0 years, 58.4% females) completed the 24-month follow-up, with 36 out of 250 knees identified as clinical knee OA. Higher DJS (OR = 1.86, 95%CI: 1.33–2.62), lower quadriceps strength (1.85, 1.05–3.23), and greater quadriceps stiffness (1.56, 1.10–2.21) were significantly associated with a higher risk of clinical knee OA. Mediation analysis showed that the DJS was not a significant mediator for the associations between quadriceps properties and knee OA.ConclusionsHigher sagittal knee dynamic joint stiffness, lower quadriceps strength, and greater quadriceps stiffness are potential risk factors for developing clinical knee OA in asymptomatic elders. Associations between quadriceps properties and knee OA may not be mediated by dynamic joint stiffness. Interventions for reducing increased passive properties of the quadriceps and knee joint stiffness may be beneficial for maintaining healthy knees in the aging population.