Principal Component Analysis for Gaussian Process Posteriors.

This letter proposes an extension of principal component analysis for gaussian process (GP) posteriors, denoted by GP-PCA. Since GP-PCA estimates a low-dimensional space of GP posteriors, it can be used for metalearning, a framework for improving the performance of target tasks by estimating a structure of a set of tasks. The issue is how to define a structure of a set of GPs with an infinite-dimensional parameter, such as coordinate system and a divergence. In this study, we reduce the infiniteness of GP to the finite-dimensional case under the information geometrical framework by considering a space of GP posteriors that have the same prior. In addition, we propose an approximation method of GP-PCA based on variational inference and demonstrate the effectiveness of GP-PCA as meta-learning through experiments.

Epidemiology of locomotive syndrome using updated clinical decision limits: 6-year follow-ups of the ROAD study.

INTRODUCTION: Locomotive syndrome (LOCOMO) is defined by the Japanese Orthopaedic Association (JOA) as a condition requiring nursing care due to a decline in mobility resulting from musculoskeletal disorders. In 2020, the JOA announced the new definition of LOCOMO stage 3 and revision of clinical decision limits in stages of LOCOMO. However, there are few reports on the epidemiological indices of LOCOMO. This prospective cohort study aimed to investigate the prevalence, incidence, and association of poor prognosis with LOCOMO stages. MATERIALS AND METHODS: The third survey of the Research on Osteoarthritis/Osteoporosis Against Disability (ROAD) study was conducted during 2012-2013, examining a population-based cohort of 1575 participants (513 men and 1062 women, mean age 65.6 years). Three LOCOMO risk tests were performed, and patients were classified into LOCOMO stages 0, 1, 2, and 3. They were followed up for 6 years, and identical examination of LOCOMO was performed in 3- and 6-year follow-ups. Data on patients' prognoses, including disability and death, were collected. RESULTS: The prevalence of LOCOMO stages 1, 2, and 3 was 41.3, 14.9, and 11.6%, respectively. The incidence of LOCOMO stages 1, 2, and 3 were 83.7, 23.0, and 18.6 per 1000 person-years, respectively. Compared with LOCOMO stage 0, logistic regression analysis showed that LOCOMO stage 3 significantly increased the risk of disability and mortality. In addition, each value of LOCOMO risk tests for LOCOMO stage 3 increased the risk of poor prognosis. CONCLUSION: LOCOMO stage 3 is a sensitive indicator of future disability and mortality.

The one-leg portion of the Stand-Up Test predicts fall risk in aged individuals: A prospective cohort study.

BACKGROUND: Falls are a primary cause of physical disability in older adults, making them a major public health problem. Locomotive syndrome risk assessments have proven to be simple to administer, practical, and useful as screening tools in detecting decreased mobility in middle-aged and elderly adults. The current prospective study investigated whether these tests were associated with future falls among elderly Japanese. METHODS: This study was a two-year prospective observational study. A total of 1800 individuals (aged 65-79 years) who were without certification of long-term care or physical disability were initially invited through letters to participate in the study. Of these, 499 individuals (225 men, 274 women) agreed to participate and underwent baseline assessments. Demographic information, body function physical performance measurements, and locomotive syndrome risk tests [Stand-Up Test (SUT), Two-Step Test (TST), and the 25-question Geriatric Locomotive Function Scale (GLFS-25)] were assessed. Following baseline evaluation, we sent a follow-up questionnaire to assess fall history in the past two years. Participants were classified as either "non-fallers" or "fallers" (denoted by one or more falls). Multiple logistic regression was used to evaluate the association between falls and each factor by providing adjusted odds ratio estimates. RESULTS: The follow-up questionnaire was returned by 399 participants, 54 of whom (13.5%) fell at least once during the two-year observation period. The multiple logistic regression analysis revealed that difficulty with standing on one leg from a 40-cm-high seat (a portion of the SUT) was a significant predictor of future falls (odds ratio = 2.20, 95%CI = 1.04-4.69, p = 0.04). A history of falling was also a risk factor of falls. CONCLUSION: Our results suggest that standing on one leg from a 40-cm-high seat is predictive of falling in older adults, even after adjustment for previous falls and other confounding variables.

Reference values for the locomotive syndrome risk test quantifying mobility of 8681 adults aged 20-89 years: A cross-sectional nationwide study in Japan.

BACKGROUND: The locomotive syndrome risk test was developed to quantify the decrease in mobility among adults, which could eventually lead to disability. The purpose of this study was to establish reference values for the locomotive syndrome risk test for adults and investigate the influence of age and sex. METHODS: We analyzed 8681 independent community dwellers (3607 men, 5074 women). Data pertaining to locomotive syndrome risk test (the two-step test, the stand-up test, and the 25-question geriatric locomotive function scale [GLFS-25]) scores were collected from seven administrative areas of Japan. RESULTS: The reference values of the three test scores were generated and all three test scores gradually decreased among young-to-middle-aged individuals and rapidly decreased in individuals aged over 60 years. The stand-up test score began decreasing significantly from the age of 30 years. The trajectories of decrease in the two-step test score with age was slightly different between men and women especially among the middle-aged individuals. The two physical test scores were more sensitive to aging than the self-reported test score. CONCLUSION: The reference values generated in this study could be employed to determine whether an individual has mobility comparable to independent community dwellers of the same age and sex.

[Prevention of osteoporosis during pregnancy and lactation period.]

Post-pregnant osteoporosis, characterized by low back pain and vertebral fractures, is a relatively rare disease. For avoiding post-pregnant osteoporosis and decrease in bone mass during pregnancy or lactation period, it is necessary to obtain sufficient bone mass during the growth period and maintain bone mass in adulthood. From the results of the national nutrition and health survey, the total energy, protein, calcium intake of women aged 20s and 30s is the lowest in all ages. In addition, young women with exercise habits are less than 10%. In addition to the prevention of post-pregnant osteoporosis, to avoid future osteoporosis and fragility fractures of older age, it is necessary to promote young women to take measures such as adequate nutrition intake and exercise habits, considering bone health.

Identifying elderly people at risk for cognitive decline by using the 2-step test.

[Purpose] The purpose is to verify the effectiveness of the 2-step test in predicting cognitive decline in elderly individuals. [Subjects and Methods] One hundred eighty-two participants aged over 65 years underwent the 2-step test, cognitive function tests and higher level competence testing. Participants were classified as Robust, <1.3, and <1.1 using criteria regarding the locomotive syndrome risk stage for the 2-step test, variables were compared between groups. In addition, ordered logistic analysis was used to analyze cognitive functions as independent variables in the three groups, using the 2-step test results as the dependent variable, with age, gender, etc. as adjustment factors. [Results] In the crude data, the <1.3 and <1.1 groups were older and displayed lower motor and cognitive functions than did the Robust group. Furthermore, the <1.3 group exhibited significantly lower memory retention than did the Robust group. The 2-step test was related to the Stroop test (ß: 0.06, 95% confidence interval: 0.01-0.12). [Conclusion] The finding is that the risk stage of the 2-step test is related to cognitive functions, even at an initial risk stage. The 2-step test may help with earlier detection and implementation of prevention measures for locomotive syndrome and mild cognitive impairment.

[Osteoporosis Liaison Service and exercise regimens, based on Locomotive Syndrome.]

The purpose of Osteoporosis Liaison Service(OLS)is primary and secondary prevention of osteoporosis and fragility fracture by multiple medical occupations. Exercise instruction and exercise intervention are important factors in OLS. Exercise has effects of increasing bone density and preventing falls. In OLS, it is also necessary to disseminate knowledge on osteoporosis and fractures to the public. Main measures against locomotive syndrome(LS), meaning weakening of ambulatory ability, are exercise and nutrition, and the LS prevention campaign is thought to lead to prevention of falls. In addition, LS is in common with OLS because it aims to spread such preventive measures widely. Exercise for LS prevention can be used safely and effectively at hospitals and workshops, as well as regional comprehensive care system.

[The significance of exercises and sports in the locomotive syndrome prevention.]

In Japan, the world's fastest aging country, the locomotive syndrome that shows a decrease in the mobility due to dysfunctions of the locomotor organs is a major risk factor of long-term care need in the old age. Exercises and sports habits are well reviewed to lead to the improvement and maintenance of motor function, and exercises are also useful in the prevention of a number of musculoskeletal diseases. In addition, several trials with the exercise intervention indicated improvement in motor function, suggesting exercises could prevent the locomotive syndrome. In future, prevalence of exercise habits may lead to decrease the prevalence of locomotive syndrome, resulting in elongation of the healthy life span.

Effect of a simple and adherent home exercise program on the physical function of community dwelling adults sixty years of age and older with pre-sarcopenia or sarcopenia.

[Purpose] To evaluate the effect of a home exercise program on physical function in community dwelling elderly with pre-sarcopenia or sarcopenia. [Subjects and Methods] Fifty-two community-dwelling individuals, over 60 years and meeting the diagnostic criteria for pre-sarcopenia or sarcopenia, were randomly assigned to intervention group (n=34) and control group (n=18). The intervention group completed 6-months home exercise programs, combining walking with lower limb resistance exercises. Body mass index, skeletal mass index, body fat percentage, handgrip strength, single-leg standing, walking speed (comfortable and maximal), and knee extension strength were evaluated at baseline and post-intervention. Activity was assessed using the 25-question Geriatric Locomotive Functional Scale (GLFS-25) and quality of life using the Euro QOL questionnaire. [Results] Pre- and post-training assessments were completed by 76.5% and 77.8% of participants in the intervention and control groups, respectively. The intervention improved single-leg standing (60.5 s to 77.2 s) and knee extension strength (1.38 Nm/kg to 1.69 Nm/kg). In the control group, maximum walking speed (2.02 m/s to 1.86 m/s) and GLFS-25 score (2.9 to 5.1) worsened. Change of pre-sarcopenia/sarcopenia status was comparable for the intervention (15.4%) and control (14.3%) groups. [Conclusion] A 6-month home exercise program improved physical function in community-dwelling individuals with pre-sarcopenia or sarcopenia.

Development of a screening program to assess motor function in the adult population: a cross-sectional observational study.

BACKGROUND: Motor dysfunction is a major reason why the elderly lose their independence in their daily lives. The concept of locomotive syndrome has been proposed to describe the risk of mobility dependence caused by various locomotive organ disorders. The preservation of locomotive organs is now socially important in the middle-aged and geriatric population. Therefore, it is important to establish a screening program to evaluate motor function and related quality of life in a wide range of ages. METHODS: We propose a new set of pre-existing scales (the Two-Step test, Stand-Up test, and 25-question Geriatric Locomotive Function Scale) as screening tools to identify the population at high risk for locomotive syndrome. We performed a preliminary survey on 777 subjects who had no apparent disorders related to motor function. We also examined the reliability of the Two-Step test and Stand-Up test. RESULTS: We found that each scale did not show ceiling or floor effects in various age groups. Because the correlations between the three scales were significant but weak, we assume that each scale covers different aspects of mobility. The test-retest reliability was found to be satisfactory for the Two-Step test and the Stand-Up test. CONCLUSION: Our results suggest that our "Short Test Battery for Locomotive syndrome" is a feasible and reliable tool for screening the adult population as a preventative strategy for locomotive syndrome in a super-aged society.

[On "2015 Guidelines for Prevention and Treatment of Osteoporosis". Osteoporosis in relation to locomotive syndrome].

In the super-aged society of Japan, both osteoporosis and locomotive syndrome are important together from a point of view of the extension of the healthy life expectancy. Osteoporosis is an significant constituting disease of locomotive syndrome, and the measures for locomotive syndrome are important to the prevention of osteoporotic fracture, because it influences the risk of falling. Actually, a rating system and the measures for locomotive syndrome have significant relationship with evaluation and decreace of the risk of falling. To reduce the osteoporotic fracture in Japan, the spread of measures for locomotive syndrome are necessary, as well as the increase of a treatment rate of osteoporosis.

[Fall risk and fracture. Locomotive syndrome and fall].

Locomotive syndrome means a condition at a risk for requiring nursing care due to deteriorated musculoskeletal organs in the middle-aged and older people. Considering that this concept aims to care prevention and that fracture for fall consists of one-tenth of causes for requiring using care, fall prevention should be an important goal of preventing or improving locomotive syndrome. As a matter of fact, locomotion check - a short form for predicting locomotive syndrome- contains items evaluating fall risk, and locomotion training - recommended exercises designated for strengthening muscles of lower extremities and balance - likely to decrease future incidence of falls. Thus, locomotive syndrome seems to be deeply related to prevention of falls as well as care prevention.

ATNAS: Automatic Termination for Neural Architecture Search.

Neural architecture search (NAS) is a framework for automating the design process of a neural network structure. While the recent one-shot approaches have reduced the search cost, there still exists an inherent trade-off between cost and performance. It is important to appropriately stop the search and further reduce the high cost of NAS. Meanwhile, the differentiable architecture search (DARTS), a typical one-shot approach, is known to suffer from overfitting. Heuristic early-stopping strategies have been proposed to overcome such performance degradation. In this paper, we propose a more versatile and principled early-stopping criterion on the basis of the evaluation of a gap between expectation values of generalisation errors of the previous and current search steps with respect to the architecture parameters. The stopping threshold is automatically determined at each search epoch without cost. In numerical experiments, we demonstrate the effectiveness of the proposed method. We stop the one-shot NAS algorithms and evaluate the acquired architectures on the benchmark datasets: NAS-Bench-201 and NATS-Bench. Our algorithm is shown to reduce the cost of the search process while maintaining a high performance.

Independent association of joint space narrowing and osteophyte formation at the knee with health-related quality of life in Japan: a cross-sectional study.

OBJECTIVE: To clarify the individual associations of joint space narrowing (JSN) and osteophytosis at the knee with quality of life (QOL) in Japanese men and women using a large-scale population-based cohort from the Research on Osteoarthritis Against Disability (ROAD) study. METHODS: The associations of minimum joint space width (JSW) and osteophyte area in the medial compartment of the knee with QOL parameters, such as the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), were examined. Minimum JSW and osteophyte area in the medial compartment of the knee were measured using a computer-aided system for the diagnosis of knee osteoarthritis. RESULTS: Of the 3,040 participants in the ROAD study, the present study included 2,039 participants age 40 years or older who completed the questionnaires (741 men and 1,298 women with a mean ± SD age of 68.6 ± 10.9 years). Multiple regression analysis after adjustment for age and body mass index showed that minimum JSW was significantly associated with scores on the pain domains of the WOMAC in men and women, while osteophyte area was significantly associated with scores on the physical function domains of the WOMAC in men and women. CONCLUSION: The findings of this cross-sectional study using a large-scale population from the ROAD study indicate that JSN and osteophytosis are independently associated with QOL.

[Locomotive syndrome and frailty. Concepts and methods of locomotion training].

Locomotive syndrome means a condition of need for long-term care or a condition at the possible risk of it, due to weakening of locomotive organs, which is, in other words, frailty of mobility. Locomotion training is all exercises that help prevention or remediation from locomotive syndrome and the centerpieces of them consist of squats and single-leg standing exercises. This article explains the concepts of locomotion training and the actual manual of those two exercises. It will greatly help instructing patients or many other old people in communities or care facilities.

[Evaluation methods of therapeutic effects of drugs for osteoporosis].

"The guideline for prevention and treatment of osteoporosis 2011" shows methods and precautions for evaluations of therapeutic effects of drugs for osteoporosis, in terms of bone mineral measurements, bone turnover markers, and vertebral deformities and fractures. Bone mineral measurements are effective, but responsible for just some part of the observed reduction in the risk of vertebral fracture. Bone turnover markers enable early and easy evaluations for the effectiveness of drugs, such as bone-resorption inhibitors or bone-formation accelerators. In particular, TRACP-5b and P1NP are user-friendly, because of small daily and day-to-day variations, as well as large amount of changes with therapy. SQ methods are well designed for X-ray evaluations of vertebral deformities and fractures with high convenience and reproducibility, good for not only epidemiological study, but daily practice.

Validity, Responsiveness, and Predictive Ability of the Japanese Version of the Cumulated Ambulation Score in Patients with Hip Fracture.

OBJECTIVES: The aim of the current study was to investigate the validity, the responsiveness, and the predictive ability for discharge to own home of the Japanese version of the Cumulated Ambulation Score (CAS-JP). This was achieved by analyzing the CAS-JP after hip fracture surgery at multiple time points until patient discharge. METHODS: Patients who underwent hip fracture surgery were evaluated using CAS-JP, the Barthel Index, and walking ability on postoperative day (POD) 1, 7, and 14 and at discharge. Floor and ceiling effects, responsiveness, and correlations between CAS-JP and other functional outcomes were assessed at each time point. The predictive ability of CAS-JP for discharge to own home was also analyzed using the area under the curve (AUC) of the receiver operating characteristic. RESULTS: A total of 121 patients were included in this study. On POD7, POD14, and at discharge, strong correlations were observed between CAS-JP and the Barthel Index (r=0.81, 0.82, and 0.87, respectively), and between CAS-JP and walking status (r=0.82, 0.81, and 0.76, respectively). CAS-JP had a large effect size (1.64-2.25) and standardized response mean (1.49-1.81). The predictive ability of CAS-JP for discharge to own home, as indicated by the AUCs, were 0.73 (95% CI: 0.62-0.83) on POD7 and 0.74 (95% CI: 0.62-0.86) on POD14. CONCLUSIONS: CAS-JP has sufficient validity and responsiveness as a mobility assessment tool in postoperative hip fracture patients. Furthermore, this study showed that early postoperative mobility status evaluation using CAS-JP can sufficiently predict discharge to own home.

Cytokine receptor-like factor 1 is highly expressed in damaged human knee osteoarthritic cartilage and involved in osteoarthritis downstream of TGF-beta.

Osteoarthritis (OA) is the most prevalent joint disease and is characterized by pain and functional loss of the joint. However, the pathogenic mechanism of OA remains unclear, and no drug therapy for preventing its progress has been established. To identify genes related to the progress of OA, the gene expression profiles of paired intact and damaged cartilage obtained from OA patients undergoing joint substitution were compared using oligo microarrays. Using functional categorization combined with gene ontology and a statistical analysis, five genes were found to be highly expressed in damaged cartilage (HBEGF, ASUS, CRLF1, LOX, CDA), whereas three genes were highly expressed in intact tissues (CHST2, PTPRD, CPAN6). Among these genes, the upregulated expression of CRLF1 was reconfirmed using real-time PCR, and the in vivo expression of CRLF1 was detected in clusters of chondrocytes and fibrocartilage-like cells in damaged OA cartilages using in situ hybridization. In vitro, the transcriptional level of CRLF1 was positively regulated by TGF-beta1 in the mouse chondrogenic cell line ATDC5. Additionally, the CRLF1/CLC complex promoted the proliferation of ATDC5 cells and suppressed the expression level of aggrecan and type II collagen. Our data suggest that the CRLF1/CLC complex disrupts cartilage homeostasis and promotes the progress of OA by enhancing the proliferation of chondrocytes and suppressing the production of cartilage matrix. A component of the complex, CRLF1, may be useful as a biomarker of OA; and the corresponding receptor is a potential new drug target for OA.

Impact of knee and low back pain on health-related quality of life in Japanese women: the Research on Osteoarthritis Against Disability (ROAD).

Although knee and low back pain are major public health issues, little information is available on their impact on the quality of life (QOL). We have investigated the impact of knee and low back pain on the QOL in Japanese women by assessing the associations between knee pain and low back pain and various QOL domains using measures such as the Medical Outcomes Study Short Form-8, EuroQOL, and the Western Ontario and McMaster Universities Osteoarthritis Index. From the 3,040 Japanese women participating in the Research on Osteoarthritis Against Disability (ROAD) study, we analyzed data on 1,369 women >40 years old (mean age 68.4 years). We further examined the associations of Kellgren-Lawrence (KL) grade at the knee and lumbar spine and the presence of vertebral fracture (VFx) with the magnitude of QOL loss in women with knee pain and low back pain, respectively. Knee pain and low back pain were found to be significantly associated with lower QOL scores among the women comprising the study cohort. In women with knee pain KL = 4, knee osteoarthritis was strongly associated with the magnitude of QOL loss. For women with low back pain, no significant associations were found between KL grade and magnitude of QOL loss, while there was a moderate association between the latter and VFx.