Medicine (Western Health) - Research Publications
Permanent URI for this collection
Search Results
1 - 10 of 43
-
ItemNo Preview AvailableCognition in healthy older women is a predictor of 14‐year falls risk(Wiley, 2021-12)Background: Falls are a significant cause of injuries, loss of confidence, increased morbidity, and institutionalisation in all older people, with women at 50% greater risk than men. The relationship between dementia and falls is well established and 2/3 of all dementia occurs in women. In this study we explored risk factors associated with a 14 year falls risk in a community-based cohort of women, which included validated measures across a wide range of clinical domains including neuropsychological, mood, quality of life and biomarkers (including hormonal). Method: The Australian Women’s Healthy Aging Project is an longitudinal observation study, assessments every year (1991 –1999), followed by assessments in 2002, 2004, 2012 and 2014. The assessments included cognitive (as of 2002), blood, and cardiovascular disease risk assessment, and questions related to falls. After data cleaning, the remaining cohort consisted of 180 participants (Table 1). Missing data were imputed using mice random forest. To identify key risk factors associated with a 14 year falls risk, random survival (time to event) forest (RSF) machine learning was used. Result: The RSF model, using all 290+ possible predictive variables, performed well with an Out Of Bag (OOB, withheld data) prediction error (C-index) of 32.8%. The most predictive variables in the model were identified using the variable importance measure (VIM). The initial model was refined by taking the top 30 predictive variables and retraining the RSF. This refined model resulted in an improved OOB C-index of 5.8% (27%). The top 20 predictive variables, Figure 1, include those associated with cardiovascular disease risk, cognitive performance, and hormone levels (e.g., family history of heart attack, digit symbol coding, and estradiol levels). Conclusion: Ninety percent of the top 20 predictive risk variables for the 14 year fall risk in women, were from three key domains, cognition (40%), cardiovascular (25%) and hormone-related measurements (25%). Our data suggest that for long term prevention of falls these domains may be important reducing risk of falls in the senior female population.
-
ItemMuscle and Bone: An Indissoluble Union(WILEY, 2022-07)
-
ItemDefining terms commonly used in sarcopenia research: a glossary proposed by the Global Leadership in Sarcopenia (GLIS) Steering Committee(SPRINGER, 2022-12)METHODS: The aim of this paper is to define terms commonly related to sarcopenia to enable standardization of these terms in research and clinical settings. The Global Leadership Initiative in Sarcopenia (GLIS) aims to bring together leading investigators in sarcopenia research to develop a single definition that can be utilized worldwide; work on a global definition of sarcopenia is ongoing. The first step of GLIS is to develop the common terminology, or a glossary, that will facilitate agreement on a global definition of sarcopenia as well as interpretation of clinical and research findings. RESULTS: Several terms that are commonly used in sarcopenia research are defined, including self-reported measures of function and ability; objective physical performance tests; and measures related to muscle function and size. CONCLUSION: As new methods and technologies are developed, these definitions may be expanded or refined over time. Our goal is to promote this common language to describe sarcopenia and its components in clinical and research settings in order to increase clinical awareness and research interest in this important condition. We hope that the use of common terminology in sarcopenia research will increase understanding of the concept and improve communication around this important age-related condition.
-
ItemNo Preview AvailableFactor analysis to determine relative contributions of strength, physical performance, body composition and muscle mass to disability and mobility disability outcomes in older men(PERGAMON-ELSEVIER SCIENCE LTD, 2022-05)BACKGROUND: It is not known how measures of body composition, strength and physical performance are interrelated or how empirical groupings of these measures relate to disability and mobility disability. METHODS: Muscle mass was assessed by D3-creatine dilution (D3Cr muscle mass) in 1345 men (84.1 ± 4.1 years) enrolled in the Osteoporotic Fractures in Men (MrOS) study. Participants completed anthropomorphic measures, walk speed, grip strength, chair stands, and dual x-ray absorptiometry (DXA) estimated appendicular lean mass (ALM) and body fat percentage. Men reported limitations in mobility, activities of daily living (ADLs) and instrumental ADLs at initial and over 2.2 ± 0.3 years. Factor analysis reduced variables into related groups and negative binomial models calculated relative risk (RR) of factors with mobility and disability outcomes. RESULTS: Factor analysis reduced 10 variables into four factors: Factor 1, body composition, including ALM, body fat percentage, weight and muscle mass; Factor 2, body size and lean mass, including height, weight and ALM; Factor 3, muscle mass, strength and performance, including walk speed, chair stands, grip strength, and muscle mass; and Factor 4, lean mass and weight, including ALM and weight. Only Factor 3 was significantly associated (p-value < .001) with prevalent disability (RR per standard deviation increment in factor score (reflecting higher muscle mass, strength and physical performance) 0.44, 0.35-0.56) and mobility disability (RR 0.22, 0.17 0.28), and incident mobility disability (RR 0.37, 0.27-0.50). CONCLUSION: D3Cr muscle mass was the only body composition variable that co-segregated with strength and physical performance measures, and contributed to a factor that was associated with disability outcomes in older men.
-
ItemA micro-costing analysis of post-fracture care pathways: results from the International Costs and Utilities Related to Osteoporotic Fractures Study (ICUROS)(SPRINGER LONDON LTD, 2022-09)UNLABELLED: This study identified the costs and health-related quality of life impacts of several post-fracture multidisciplinary care pathways specific to individual skeletal site (hip, distal forearm, vertebrae, humerus). These care pathways may assist healthcare providers in allocating resources for osteoporotic fractures in more effective and cost-efficient ways. INTRODUCTION: This micro-costing study was undertaken to provide the estimated healthcare costs of several fracture site-specific health service use pathways associated with different trajectories of health-related quality of life (HRQoL) 12-months post-fracture. METHODS: The study included 4126 adults aged ≥ 50 years with a fragility fracture (1657 hip, 681 vertebrae, 1354 distal forearm, 434 humerus) from the International Costs & Utilities Related to Osteoporotic fractures Study (ICUROS). ICUROS participants were asked to recall the frequency and duration (where applicable) of their health and community care service use at 4- and 12-month follow-up visits. Patient-level costs were identified and aggregated to determine the average cost of healthcare use related to the fracture in each care pathway (presented in Australian 2021 dollars). Mean cost differences were calculated and analysed using a one-way analysis of variance (ANOVA) and post hoc Bonferroni correction to determine any statistically significant differences. RESULTS: The total direct cost of fractures was estimated at $89564, $38926, $18333, and $38461AUD per patient for hip, vertebral, wrist, and humeral participants, respectively. A Kruskal-Wallis test yielded a statistically significant difference in cost values between most care pathways (p < 0.001). Of the 20 care pathways, those associated with recovery of HRQoL had lower mean costs per patient across each fracture site. CONCLUSIONS: This study identified the costs and HRQoL impacts of several multidisciplinary care pathways for individual fracture sites based on the health service utilization of an international cohort of older adults. These care pathways may assist healthcare providers in allocating resources for fragility fractures in more effective and cost-efficient ways.
-
ItemNo Preview AvailableTongue muscle mass is associated with total grey matter and hippocampal volumes in Dementia with Lewy Bodies(ELSEVIER IRELAND LTD, 2022)BACKGROUND: Age-related neurodegeneration, sarcopenia, and ectopic fat accumulation are conditions with shared pathways that remain poorly understood. We have measured muscle volume and fat accumulation in masseter and tongue muscle, and aim to explore their association with the total grey matter volume using MRI in older adults recently diagnosed with Alzheimer's disease (AD) and Dementia with Lewy bodies (DLB). METHODS: In this cross-sectional study, people newly diagnosed with mild AD (n=33) and DLB (n=20) underwent structural head MRI. Muscle volume and intramuscular fat (iMAT) of the tongue and masseter were computed using Slice-O-Matic software for segmentation. Total grey volume and hippocampal volumetric segmentation were performed with the FreeSurfer image analysis suite version 6.0. Independent regression models were employed to analyse the associations. RESULTS: Tongue iMAT was higher and total grey volume lower in DLB compared to AD. In the DLB group, tongue muscle was positively associated with total grey matter volume Est 0.92 (SE 0.24 p-value 0.002), left- Est 0.01 (SE 0.0028 p-value 0,002), and right- Est 0.0088 (SE 0.0027 p-value: 0.005) hippocampal volume. There were no statistically significant results for AD. CONCLUSION: Tongue muscle volume was positively associated with hippocampal and total grey volume in DLB. Longitudinal designs are required to explore the extent and significance of this association.
-
ItemNo Preview AvailableValidation of a Semiautomatic Image Analysis Software for the Quantification of Musculoskeletal Tissues(SPRINGER, 2022-03)Accurate quantification of bone, muscle, and their components is still an unmet need in the musculoskeletal field. Current methods to quantify tissue volumes in 3D images are expensive, labor-intensive, and time-consuming; thus, a reliable, valid, and quick application is highly needed. Tissue Compass is a standalone software for semiautomatic segmentation and automatic quantification of musculoskeletal organs. To validate the software, cross-sectional micro-CT scans images of rat femur (n = 19), and CT images of hip and abdomen (n = 100) from the Osteoporotic Fractures in Men (MrOS) Study were used to quantify bone, hematopoietic marrow (HBM), and marrow adipose tissue (MAT) using commercial manual software as a comparator. Also, abdominal CT scans (n = 100) were used to quantify psoas muscle volumes and intermuscular adipose tissue (IMAT) using the same software. We calculated Pearson's correlation coefficients, individual intra-class correlation coefficients (ICC), and Bland-Altman limits of agreement together with Bland-Altman plots to show the inter- and intra-observer agreement between Tissue Compass and commercially available software. In the animal study, the agreement between Tissue Compass and commercial software was r > 0.93 and ICC > 0.93 for rat femur measurements. Bland-Altman limits of agreement was - 720.89 (- 1.5e+04, 13,074.00) for MAT, 4421.11 (- 1.8e+04, 27,149.73) for HBM and - 6073.32 (- 2.9e+04, 16,388.37) for bone. The inter-observer agreement for QCT human study between two observers was r > 0.99 and ICC > 0.99. Bland-Altman limits of agreement was 0.01 (- 0.07, 0.10) for MAT in hip, 0.02 (- 0.08, 0.12) for HBM in hip, 0.05 (- 0.15, 0.25) for bone in hip, 0.02 (- 0.18, 0.22) for MAT in L1, 0.00 (- 0.16, 0.16) for HBM in L1, and 0.02 (- 0.23, 0.27) for bone in L1. The intra-observer agreement for QCT human study between the two applications was r > 0.997 and ICC > 0.99. Bland-Altman limits of agreement was 0.03 (- 0.13, 0.20) for MAT in hip, 0.05 (- 0.08, 0.18) for HBM in hip, 0.05 (- 0.24, 0.34) for bone in hip, - 0.02 (- 0.34, 0.31) for MAT in L1, - 0.14 (- 0.44, 0.17) for HBM in L1, - 0.29 (- 0.62, 0.05) for bone in L1, 0.03 (- 0.08, 0.15) for IMAT in psoas, and 0.02 (- 0.35, 0.38) for muscle in psoas. Compared to a conventional application, Tissue Compass demonstrated high accuracy and non-inferiority while also facilitating easier analyses. Tissue Compass could become the tool of choice to diagnose tissue loss/gain syndromes in the future by requiring a small number of CT sections to detect tissue volumes and fat infiltration.
-
ItemNo Preview AvailableNew horizons in falls prevention and management for older adults: a global initiative(OXFORD UNIV PRESS, 2021-09)BACKGROUND: falls and fall-related injuries are common in older adults, have negative effects both on quality of life and functional independence and are associated with increased morbidity, mortality and health care costs. Current clinical approaches and advice from falls guidelines vary substantially between countries and settings, warranting a standardised approach. At the first World Congress on Falls and Postural Instability in Kuala Lumpur, Malaysia, in December 2019, a worldwide task force of experts in falls in older adults, committed to achieving a global consensus on updating clinical practice guidelines for falls prevention and management by incorporating current and emerging evidence in falls research. Moreover, the importance of taking a person-centred approach and including perspectives from patients, caregivers and other stakeholders was recognised as important components of this endeavour. Finally, the need to specifically include recent developments in e-health was acknowledged, as well as the importance of addressing differences between settings and including developing countries. METHODS: a steering committee was assembled and 10 working Groups were created to provide preliminary evidence-based recommendations. A cross-cutting theme on patient's perspective was also created. In addition, a worldwide multidisciplinary group of experts and stakeholders, to review the proposed recommendations and to participate in a Delphi process to achieve consensus for the final recommendations, was brought together. CONCLUSION: in this New Horizons article, the global challenges in falls prevention are depicted, the goals of the worldwide task force are summarised and the conceptual framework for development of a global falls prevention and management guideline is presented.
-
ItemNo Preview AvailableThe effects of acute exercise on bone turnover markers in middle-aged and older adults: A systematic review(ELSEVIER SCIENCE INC, 2021-02)BACKGROUND: Bone turnover is the cellular machinery responsible for bone integrity and strength and, in the clinical setting, it is assessed using bone turnover markers (BTMs). Acute exercise can induce mechanical stress on bone which is needed for bone remodelling, but to date, there are conflicting results in regards to the effects of varying mechanical stimuli on BTMs. OBJECTIVES: This systematic review examines the effects of acute aerobic, resistance and impact exercises on BTMs in middle and older-aged adults and examines whether the responses are determined by the exercise mode, intensity, age and sex. METHODS: We searched PubMed, SCOPUS, Web of Science and EMBASE up to 22nd April 2020. Eligibility criteria included randomised controlled trials (RCTs) and single-arm studies that included middle-aged (50 to 65 years) and older adults (>65 years) and, a single-bout, acute-exercise (aerobic, resistance, impact) intervention with measurement of BTMs. PROSPERO registration number CRD42020145359. RESULTS: Thirteen studies were included; 8 in middle-aged (n = 275, 212 women/63 men, mean age = 57.9 ± 1.5 years) and 5 in older adults (n = 93, 50 women/43 men, mean age = 68.2 ± 2.2 years). Eleven studies included aerobic exercise (AE, 7 middle-aged/4 older adults), and two included resistance exercise (RE, both middle-aged). AE significantly increased C-terminal telopeptide (CTX), alkaline phosphatase (ALP) and bone-ALP in middle-aged and older adults. AE also significantly increased total osteocalcin (tOC) in middle-aged men and Procollagen I Carboxyterminal Propeptide and Cross-Linked Carboxyterminal Telopeptide of Type I Collagen in older women. RE alone decreased ALP in older adults. In middle-aged adults, RE with impact had no effect on tOC or BALP, but significantly decreased CTX. Impact (jumping) exercise alone increased Procollagen Type 1 N Propeptide and tOC in middle-aged women. CONCLUSION: Acute exercise is an effective tool to modify BTMs, however, the response appears to be exercise modality-, intensity-, age- and sex-specific. There is further need for higher quality and larger RCTs in this area.
-
ItemProgressive Resistance Training for Concomitant Increases in Muscle Strength and Bone Mineral Density in Older Adults: A Systematic Review and Meta-Analysis(ADIS INT LTD, 2022-08)BACKGROUND: Older adults experience considerable muscle and bone loss that are closely interconnected. The efficacy of progressive resistance training programs to concurrently reverse/slow the age-related decline in muscle strength and bone mineral density (BMD) in older adults remains unclear. OBJECTIVES: We aimed to quantify concomitant changes in lower-body muscle strength and BMD in older adults following a progressive resistance training program and to determine how these changes are influenced by mode (resistance only vs. combined resistance and weight-bearing exercises), frequency, volume, load, and program length. METHODS: MEDLINE/PubMed and Embase databases were searched for articles published in English before 1 June, 2021. Randomized controlled trials reporting changes in leg press or knee extension one repetition maximum and femur/hip or lumbar spine BMD following progressive resistance training in men and/or women ≥ 65 years of age were included. A random-effects meta-analysis and meta-regression determined the effects of resistance training and the individual training characteristics on the percent change (∆%) in muscle strength (standardized mean difference) and BMD (mean difference). The quality of the evidence was assessed using the Cochrane risk-of-bias tool (version 2.0) and Grading of Recommendation, Assessment, Development, and Evaluation (GRADE) criteria. RESULTS: Seven hundred and eighty studies were identified and 14 were included. Progressive resistance training increased muscle strength (∆ standardized mean difference = 1.1%; 95% confidence interval 0.73, 1.47; p ≤ 0.001) and femur/hip BMD (∆ mean difference = 2.77%; 95% confidence interval 0.44, 5.10; p = 0.02), but not BMD of the lumbar spine (∆ mean difference = 1.60%; 95% confidence interval - 1.44, 4.63; p = 0.30). The certainty for improvement was greater for muscle strength compared with BMD, evidenced by less heterogeneity (I2 = 78.1% vs 98.6%) and a higher overall quality of evidence. No training characteristic significantly affected both outcomes (p > 0.05), although concomitant increases in strength and BMD were favored by higher training frequencies, increases in strength were favored by resistance only and higher volumes, and increases in BMD were favored by combined resistance plus weight-bearing exercises, lower volumes, and higher loads. CONCLUSIONS: Progressive resistance training programs concomitantly increase lower-limb muscle strength and femur/hip bone mineral density in older adults, with greater certainty for strength improvement. Thus, to maximize the efficacy of progressive resistance training programs to concurrently prevent muscle and bone loss in older adults, it is recommended to incorporate training characteristics more likely to improve BMD.
- 1 (current)
- 2
- 3
- 4
- 5