Advancing our understanding of skeletal muscle across the lifecourse: Protocol for the MASS_Lifecourse study and characteristics of the first 80 participants.

INTRODUCTION: Sarcopenia, the age-related loss of skeletal muscle strength and mass, carries a significant burden for affected individuals. There has been little investigation of sarcopenia using experimental medicine techniques to study human muscle tissue in detail. The aim of the Muscle Ageing Sarcopenia Studies Lifecourse (MASS_Lifecourse) study is to recruit up to 160 participants, equally divided between females and males between ages 45 and 85 years for detailed phenotyping of skeletal muscle health. Here we describe the protocol for the study and the characteristics of the first 80 participants. METHODS: We are recruiting participants from three sources in the north-east of England. Study fieldwork comprises a home visit (or videocall) for consent and assessment of health, cognition, lifestyle, and wellbeing. This is followed by a visit to a clinical research facility for assessment of sarcopenia status and collection of samples including a vastus lateralis muscle biopsy. We produced descriptive statistics for the first 80 participants, including expressing their grip strength relative to normative data in the form of Z-scores. RESULTS: The first 80 participants (53.8 % female) covered the target ages, ranging from 48 to 84 years. They were regularly physically active, reported good physical function and had a prevalence of sarcopenia (including probable sarcopenia) of 11.3 % based on the revised European consensus. Their grip strength was similar to that in the general population, with a mean Z-score of 0.09 standard deviations (95 % CI: -1.64, 1.83) above that expected. CONCLUSIONS: The MASS_Lifecourse study combines comprehensive health and lifestyle data with a range of biological samples including skeletal muscle. The findings from planned analyses should contribute to improvements in the diagnosis, treatment, and prevention of sarcopenia.

The assessment of sarcopenia and the frailty phenotype in the outpatient care of older people: implementation and typical values obtained from the Newcastle SarcScreen project.

PURPOSE: Sarcopenia and the frailty phenotype both indicate older adults at risk of adverse health outcomes and yet are not widely assessed in practice. We developed the Newcastle SarcScreen to enable assessment of these two ageing syndromes during clinical care. In the setting of our Older People's Medicine Day Unit, our aims were to describe the implementation of the SarcScreen and to examine the typical values obtained. METHODS: The SarcScreen comprised height, weight, questions (three on the Fried frailty phenotype and five on the SARC-F questionnaire), grip strength and gait speed. We analysed data from 552 patients completing the SarcScreen. We expressed grip strength as Z-scores (number of standard deviations above the mean expected for a patient's age and sex). RESULTS: It was possible to implement the SarcScreen. In 552 patients (65.9% females) with mean age 80.1 (7.7) years, grip strength was feasible in 98.2% and gait speed in 82.1%. Gait speed was typically not assessed due to mobility impairment. Most patients had weak grip strength (present in 83.8%), slow gait speed (88.8%) and the frailty phenotype (66.2%). We found a high prevalence of probable sarcopenia and the frailty phenotype across all age groups studied. This was reflected by low grip strength Z-scores, especially at younger ages: those aged 60-69 had grip strength 2.7 standard deviations (95% CI 2.5-2.9) below that expected. CONCLUSION: It is possible to implement an assessment of sarcopenia and the frailty phenotype as part of the routine outpatient care of older people.

Poor Appetite Is Associated with Six Month Mortality in Hospitalised Older Men and Women.

OBJECTIVES: Appetite loss is common in hospitalised older individuals but not routinely assessed. Poor appetite in hospital has previously been identified as predictive of greater mortality in the six months following discharge in a single study of female patients. The present study aimed to assess this association in a larger sample including both hospitalised men and women. DESIGN: Longitudinal observational study with six month follow up. SETTING: Acute hospital wards in a single large hospital in England. PARTICIPANTS: Older inpatients aged over 70 years. MEASUREMENTS: Appetite was assessed using the Simplified Nutritional Appetite Questionnaire (SNAQ) during hospital stay. Deaths during six month follow-up period were recorded. Association between SNAQ score during hospital admission and death 6 months post-discharge was assessed using binary logistic regression in unadjusted and adjusted analysis. RESULTS: 296 participants (43% female, mean age 83 years (SD 6.9)) were included in this study. Prevalence of poor appetite (SNAQ score <14) was 41%. In unadjusted analysis a SNAQ score of <14 was associated with a 2.47 increase in odds of mortality at six months (OR 2.47 (95% CI 1.27,4.82)). This association remained after adjusting for number of comorbidities (Charlson index), length of stay and gender (OR 2.62 (95% CI 1.30, 5.27)). In unadjusted continuous analysis, every one point decrease in SNAQ score led to a 1.20 fold increase in odds of mortality at six months (OR 1.20 (95% CI 1.06-1.36)). This association remained in adjusted analysis (OR 1.22 (95% CI 1.07-1.39)). CONCLUSION: Poor appetite is common in hospitalised older people. We have confirmed the association, previously reported in older women, between poor appetite during hospital stay and greater mortality at six months post-discharge but in a larger study including older men and women. Further research is needed to understand the mechanisms of poor appetite, which lead to increased mortality.

The identification of probable sarcopenia in early old age based on the SARC-F tool and clinical suspicion: findings from the 1946 British birth cohort.

PURPOSE: The European Working Group on Sarcopenia in Older People 2 (EWGSOP2) consensus definition introduced the concept of probable sarcopenia as a basis on which to begin treatment. Our aims were to describe the prevalence of probable sarcopenia in older adults and to investigate the utility of (1) the SARC-F tool and (2) clinical risk factors for the identification of those likely to have probable sarcopenia. METHODS: We used data from the 1946 British birth cohort at age 69, with 1686 participants included in the analyses. We used the EWGSOP2 cut points for weak grip strength and slow chair rise time, with the presence of one or both indicating probable sarcopenia. We examined the sensitivity and specificity of the SARC-F tool for probable sarcopenia. We also examined associations between clinical risk factors and probable sarcopenia. RESULTS: The prevalence of probable sarcopenia was 19%. A SARC-F score of ≥ 4 had low sensitivity (15%) and high specificity (99%) for probable sarcopenia, whereas a score of ≥ 1 had higher sensitivity (65%) and reasonable specificity (72%). Three clinical risk factors were independently associated with probable sarcopenia: polypharmacy [OR 2.7 (95% CI 1.7, 4.2)], lower body osteoarthritis [OR 1.8 (95% CI 1.3, 2.6)] and physical inactivity [OR of 2.1 (95% CI 1.5, 2.8)]. CONCLUSION: We have shown that EWGSOP2 probable sarcopenia is common in community-dwelling adults in early old age. Those with any positive responses to the questions in the SARC-F tool, a history of polypharmacy, lower body osteoarthritis or physical inactivity should be prioritised for the assessment of muscle strength.

Priorities for research in multiple conditions in later life (multi-morbidity): findings from a James Lind Alliance Priority Setting Partnership.

INTRODUCTION: multiple conditions in later life (multi-morbidity) is a major challenge for health and care systems worldwide, is of particular relevance for older people, but has not (until recently) received high priority as a topic for research. We have identified the top 10 research priorities from the perspective of older people, their carers, and health and social care professionals using the methods of a James Lind Alliance Priority Setting Partnership. METHODS: in total, 354 participants (162 older people and carers, 192 health professionals) completed a survey and 15 older people and carers were interviewed to produce 96 'unanswered questions'. These were further refined by survey and interviews to a shortlist of 21 topics, and a mix of people aged 80+ living with three or more conditions, carers and health and social care providers to prioritised the top 10. RESULTS: the key priorities were about the prevention of social isolation, the promotion of independence and physical and emotional well-being. In addition to these broad topics, the process also identified detailed priorities including the role of exercise therapy, the importance of falls (particularly fear of falling), the recognition and management of frailty and Comprehensive Geriatric Assessment. CONCLUSION: these topics provide a unique perspective on research priorities on multiple conditions in later life and complement existing UK and International recommendations about the optimisation of health and social care systems to deliver essential holistic models of care and the prevention and treatment of multiple co-existing conditions.

Mitochondrial respiratory chain function and content are preserved in the skeletal muscle of active very old men and women.

INTRODUCTION: The loss of mitochondrial function and content have been implicated in sarcopenia although they have been little studied in the very old, the group in which sarcopenia is most common. In this pilot study, our aim was to determine if mitochondrial respiratory chain function and content are preserved among healthy 85-year-olds. METHODS: We recruited 19 participants (11 female) through their general practitioner and assessed their medical history, functional status and self-reported physical activity. We identified sarcopenia using grip strength, Timed Up-and-Go and bioimpedance analysis. We assessed mitochondrial respiratory chain function using phosphorous magnetic resonance spectroscopy, estimating τ1/2 PCr, the recovery half-time of phosphocreatine in the calf muscles following a bout of aerobic exercise. We performed a biopsy of the vastus lateralis muscle and assessed mitochondrial respiratory chain content by measuring levels of subunits of complex I and IV of the respiratory chain, expressed as Z-scores relative to that in young controls. RESULTS: Participants had a median (IQR) of 2 (1,3) long-term conditions, reported regular aerobic physical activity, and one participant (5.3%) had sarcopenia. Sixteen participants completed the magnetic resonance protocol and the mean (SD) τ1/2 PCr of 35.6 (11.3) seconds was in keeping with preserved mitochondrial function. Seven participants underwent muscle biopsy and the mean fibre Z-scores were -0.7 (0.7) and -0.2 (0.4) for complexes I and IV, respectively, suggesting preserved content of mitochondrial respiratory chain enzymes. CONCLUSION: Muscle mitochondrial respiratory chain function and content are preserved in a sample of active, well-functioning 85-year-olds, among whom sarcopenia was uncommon. The results from this study will help inform future work examining the association between muscle mitochondrial deficiency and sarcopenia.

Can measures of physical performance in mid-life improve the clinical prediction of disability in early old age? Findings from a British birth cohort study.

BACKGROUND: Poor performance in physical tests such as grip strength and walking speed is a risk factor for disability in old age, although whether such measures improve the discrimination of clinical prediction models when traditional clinical risk factors are already known is not clear. The prevalence of disability in mid-life is relatively low and hence screening in this age group may present an opportunity for early identification of those at increased future risk who may benefit most from preventative interventions. METHODS: Data were drawn from two waves of the Medical Research Council National Survey of Health and Development. We examined whether several chronic conditions, poor health behaviours and lower scores on three measures of physical performance (grip strength, chair rise speed and standing balance time) at age 53 were associated with self-reported mobility and/or personal care disability at age 69. We used the area under the curve statistic (AUC) to assess model discrimination. RESULTS: At age 69, 44% (826/1855) of participants reported mobility and/or personal care disability. Our final clinical prediction model included sex, knee osteoarthritis, taking 2+ medications, smoking, increased BMI and poor performance in all three physical tests, with an AUC of 0.740 compared with 0.708 for a model which did not include the performance measures. CONCLUSION: Measures of physical performance in midlife improve discrimination in clinical prediction models for disability over 16 years. Importantly, these and similar measures are also potential targets of future diet, exercise and pharmacological intervention in mid-life.

Physical activity among hospitalised older people: insights from upper and lower limb accelerometry.

BACKGROUND: Few studies have explored the activity levels of hospitalised older people and the intra-daily activity patterns in this group have not been described. AIMS: To describe the quantity and daily pattern of physical activity among hospitalised older people using two accelerometers: the ankle-worn StepWatch Activity Monitor (SAM), and the wrist-worn GENEActiv. METHODS: This cross-sectional observational study was conducted on the acute medical wards for older people in one UK hospital. INCLUSION CRITERIA: participants aged ≥ 70 years, and able to mobilise prior to admission. Participants wore both devices for up to seven consecutive days, or until hospital discharge, whichever was sooner. Intra-daily activity levels were analysed hourly over each 24 h period. RESULTS: 38 participants (mean age 87.8 years, SD 4.8) had their activity levels measured using both devices. The SAM median daily step count was 600 (IQR 240-1427). Intra-daily activity analysis showed two peak periods of ambulatory activity between 9 am-11 am and 6 pm-7 pm. With physical activity defined as ≥ 12 milli-g (GENEActiv), the median time spent above this cut-off point was 4.2 h. 62% of this activity time was only sustained for 1-5 min. Acceptability of both devices was high overall, but the wrist-worn device (96%) was more acceptable to patients than the ankle-worn device (83%). CONCLUSION: Activity levels of these hospitalised older people were very low. Most physical activity was sustained over short periods. The intra-daily pattern of activity is an interesting finding which can help clinicians implement time-specific interventions to address the important issue of sedentary behaviour.

Assessment of Physical Activity of Hospitalised Older Adults: A Systematic Review.

BACKGROUND: The assessment of physical activity levels of hospitalised older people requires accurate and reliable measures. Physical activities that older people in hospital commonly engage in include exercises and walking. Measurement of physical activity levels of older inpatients is essential to evaluate the impact of interventions to improve physical activity levels and to determine associations between physical activity in hospital and other health-related outcome measures. OBJECTIVE: To determine which measures are used to measure physical activity of older people in hospital, and to describe their properties and applications. METHOD: A systematic review of four databases: Medline, Embase, CINAHL and AMED was conducted for papers published from 1996 to 2016. Inclusion criteria were participants aged ≥ 65 years and studies which included measures of physical activity in the acute medical inpatient setting. Studies which specifically assessed the activity levels of surgical patients or patients with neurological conditions such as stroke or brain injury were excluded. All study designs were included in the review. RESULTS: 18 studies were included from 127 articles selected for full review. 15 studies used objective measures to measure the physical activity of older inpatients: 11 studies used accelerometers and four used direct systematic observations. Seven accelerometers were identified including the StepWatch Activity Monitor, activPAL, GENEActiv, Kenz Lifecorder EX, Actiwatch-L, Tractivity and AugmenTech Inc. Pittsburgh accelerometer. Three studies used a subjective measure (interviews with nurses and patients) to classify patients into low, intermediate and high mobility groups. The StepWatch Activity Monitor was reported to be most accurate at step-counting in patients with slow gait speed or altered gait. The activPAL was reported to be highly accurate at classifying postures. CONCLUSION: Physical activity levels of older inpatients can be measured using accelerometers. The accuracy of the accelerometers varies between devices and population-specific validation studies are needed to determine their suitability in measuring physical activity levels of hospitalised older people. Subjective measures are less accurate but can be a practical way of measuring physical activity in a larger group of patients.

Muscle Mass, Muscle Morphology and Bone Health Among Community-Dwelling Older Men: Findings from the Hertfordshire Sarcopenia Study (HSS).

Sarcopenia and osteoporosis are associated with poor health outcomes in older people. Relationships between muscle and bone have typically been reported at a functional or macroscopic level. The aims of this study were to describe the relationships between muscle morphology and bone health among participants of the Hertfordshire Sarcopenia Study (HSS). 105 older men, mean age 72.5 (SD 2.5) years, were recruited into the HSS. Whole body lean mass as well as appendicular lean mass, lumbar spine and femoral neck bone mineral content (BMC) and bone mineral density (BMD) were obtained through dual-energy X-ray absorptiometry scanning. Percutaneous biopsy of the vastus lateralis was performed successfully in 99 participants. Image analysis was used to determine the muscle morphology variables of slow-twitch (type I) and fast-twitch (type II) myofibre area, myofibre density, capillary and satellite cell (SC) density. There were strong relationships between whole and appendicular lean body mass in relation to femoral neck BMC and BMD (r ≥ 0.43, p < 0.001). Type II fibre area was associated with both femoral neck BMC (r = 0.27, p = 0.01) and BMD (r = 0.26, p = 0.01) with relationships robust to adjustment for age and height. In unadjusted analysis, SC density was associated with whole body area (r = 0.30, p = 0.011) and both BMC (r = 0.26, p = 0.031) and area (r = 0.29, p = 0.017) of the femoral neck. We have demonstrated associations between BMC and changes in muscle at a cellular level predominantly involving type II myofibres. Interventions targeted at improving muscle mass, function and quality may improve overall musculoskeletal health. Larger studies that include women are needed to explore these relationships further.

The Impact of Trained Volunteer Mealtime Assistants on Dietary Intake and Satisfaction with Mealtime Care in Adult Hospital Inpatients: A Systematic Review.

BACKGROUND: Malnutrition is common in hospital inpatients and is associated with increased morbidity and mortality. Insufficient assistance at mealtimes can contribute to this and therefore trained volunteer mealtime assistants may be of benefit. OBJECTIVES: To identify and review the current evidence for the impact of trained volunteer mealtime assistants on dietary intake and satisfaction with mealtime care in adult hospital inpatients. METHODS: A systematic search of Medline, Embase and CINAHL was conducted to identify relevant articles. Articles of any methodology were considered. Quality assessment and data extraction were carried out by two reviewers independently. PARTICIPANTS: Participants were inpatients in a hospital setting, including rehabilitation units. Participants in long term care facilities were excluded. INTERVENTION: Articles that examined the effect of trained volunteer mealtime assistants on nutritional outcomes or satisfaction with mealtime care were included. RESULTS: 5576 articles were identified, of which 14 were included in the review. Nine were small research studies and five were quality improvement initiatives. The quality of eight studies was moderate, with one study being of lower quality. Eight articles reported dietary intake and seven demonstrated an improvement, with protein intakes at volunteer mealtimes increasing by 4.3g-10.1g and energy intakes by 44-105kcal. Ten articles reported positive staff, patient and volunteer feedback. No adverse events were reported. CONCLUSION: There is evidence from small studies and improvement projects that trained volunteer mealtime assistants are safe and improve satisfaction with mealtime care in hospital inpatients, although evidence for an effect on dietary intake was less consistent. Larger studies with robust methodology are required to confirm this.

Development of a Short Questionnaire to Assess Diet Quality among Older Community-Dwelling Adults.

OBJECTIVE: To evaluate the use of a short questionnaire to assess diet quality in older adults. DESIGN: Cross-sectional study. SETTING: Hertfordshire, UK. PARTICIPANTS: 3217 community-dwelling older adults (59-73 years). MEASUREMENTS: Diet was assessed using an administered food frequency questionnaire (FFQ); two measures of diet quality were defined by calculating participants' 'prudent diet' scores, firstly from a principal component analysis of the data from the full FFQ (129 items) and, secondly, from a short version of the FFQ (including 24 indicator foods). Scores calculated from the full and short FFQ were compared with nutrient intake and blood concentrations of vitamin C and lipids. RESULTS: Prudent diet scores calculated from the full FFQ and short FFQ were highly correlated (0.912 in men, 0.904 in women). The pattern of associations between nutrient intake (full FFQ) and diet scores calculated using the short and full FFQs were very similar, both for men and women. Prudent diet scores calculated from the full and short FFQs also showed comparable patterns of association with blood measurements: in men and women, both scores were positively associated with plasma vitamin C concentration and serum HDL; in women, an inverse association with serum triglycerides was also observed. CONCLUSIONS: A short food-based questionnaire provides useful information about the diet quality of older adults. This simple tool does not require nutrient analysis, and has the potential to be of value to non-specialist researchers.

The Impact of Trained Volunteer Mealtime Assistants on the Dietary Intake of Older Female In-Patients: The Southampton Mealtime Assistance Study.

OBJECTIVE: Malnutrition among older hospital inpatients is common and is associated with poor clinical outcomes. Time-pressured staff may struggle to provide mealtime assistance. This study aimed to evaluate the impact of trained volunteer mealtime assistants on the dietary intake of older inpatients. DESIGN: Quasi-experimental two year pre and post- test study of the introduction of volunteer mealtime assistants to one acute medical female ward, with contemporaneous comparison with a control ward. SETTING: Two acute medical female wards in a university hospital in England. PARTICIPANTS: Female acute medical inpatients aged 70 years and over who were not tube fed, nil by mouth, terminally ill or being nursed in a side room. INTERVENTION: The introduction of volunteer mealtime assistants to one ward to help patients during weekday lunchtimes in the intervention year. MEASUREMENTS: Patients' background and clinical characteristics were assessed; 24-hour records were completed for individual patients to document dietary intake in both years on the two wards. RESULTS: A total of 407 patients, mean (SD) age 87.5 (5.4) years, were studied over the two-year period; the majority (57%) needed mealtime assistance and up to 50% were confused. Patients' clinical characteristics did not differ between wards in the observational or intervention years. Throughout the intervention year volunteers provided mealtime assistance on weekday lunchtimes on the intervention ward only. Daily energy (median 1039 kcal; IQR 709, 1414) and protein (median 38.9 g: IQR 26.6, 54.0) intakes were very low (n=407). No differences in dietary intake were found between the wards in the observational or intervention years, or in a pre-post-test comparison of patients on the intervention ward. Data were therefore combined for further analysis to explore influences on dietary intake. In a multivariate model, the only independent predictor of energy intake was the feeding assistance required by patients; greater need for help was associated with lower energy intake (P<0.001). Independent predictors of protein intake were the feeding assistance given (P<0.001) and use of sip feeds; sip feed users had slightly higher protein intakes (P=0.014). CONCLUSIONS: Trained volunteers were able to deliver mealtime assistance on a large scale in an effective and sustainable manner, with the potential to release time for nursing staff to complete other clinical tasks. The study participants had a low median intake of energy and protein highlighting the importance of patient factors associated with acute illness; a stratified approach including oral and parenteral nutritional supplementation may be required for some acutely unwell patients. The level of mealtime assistance required was the factor most strongly associated with patients' poor intake of energy and protein and may be a useful simple indicator of patients at risk of poor nutrition.

Heavy manual work throughout the working lifetime and muscle strength among men at retirement age.

INTRODUCTION: Reductions in heavy manual work as a consequence of mechanisation might adversely impact muscle strength at older ages. We investigated the association between grip strength at retirement age and lifetime occupational exposure to physically demanding activities. Grip strength is an important predictor of long-term health and physical function in older people. METHODS: Grip strength (maximum of three readings in each hand) was measured in men from the Hertfordshire Cohort Study at a single examination when their mean age was 65.8 (SD 2.9) years. Associations with lifetime occupational exposure (ascertained by questionnaire) to three activities (standing/walking ≥ 4 h/day; lifting ≥ 25 kg; and energetic work sufficient to induce sweating) were assessed by multivariable linear regression with adjustment for various potential confounders. RESULTS: Complete data were available from 1418 men who had worked for at least 20 years. After adjustment for age, height and weight, those with longer exposures to walking/standing and heavy lifting had lower grip strength, but the relationship disappeared after further adjustment for confounders. Working at physical intensity sufficient to induce sweating was not significantly associated with grip strength. CONCLUSIONS: We found no evidence that physically demanding occupational activities increase hand grip strength at normal retirement age. Any advantages of regular physical occupational activity may have been obscured by unmeasured socioeconomic confounders.

Measuring Appetite with the Simplified Nutritional Appetite Questionnaire Identifies Hospitalised Older People at Risk of Worse Health Outcomes.

OBJECTIVES: Poor appetite is commonly reported by older people but is rarely measured. The Simplified Nutritional Appetite Questionnaire (SNAQ) was validated to predict weight loss in community dwelling older adults but has been little used in hospitals. We evaluated it in older women on admission to hospital and examined associations with healthcare outcomes. DESIGN: Longitudinal observational with follow-up at six months. SETTING: Female acute Medicine for Older People wards at a University hospital in England. PARTICIPANTS: 179 female inpatients. MEASUREMENTS: Age, weight, Body Mass Index (BMI), grip strength, SNAQ, Barthel Index Score, Mini Mental State Examination (MMSE), Geriatric Depression Scale: Short Form (GDS-SF), Malnutrition Universal Screening Tool (MUST), category of domicile and receipt of care were measured soon after admission and repeated at six month follow-up. The length of hospital stay (LOS), hospital acquired infection, readmissions and deaths by follow-up were recorded. RESULTS: 179 female participants mean age 87 (SD 4.7) years were recruited. 42% of participants had a low SNAQ score (<14, indicating poor appetite). A low SNAQ score was associated with an increased risk of hospital acquired infection (OR 3.53; 95% CI: 1.48, 8.41; p=0.004) and with risk of death (HR 2.29; 95% CI: 1.12, 4.68; p = 0.023) by follow-up. CONCLUSION: Poor appetite was common among the older hospitalised women studied, and was associated with higher risk of poor healthcare outcomes.

Non-invasive Assessment of Lower Limb Geometry and Strength Using Hip Structural Analysis and Peripheral Quantitative Computed Tomography: A Population-Based Comparison.

Hip fracture is the most significant complication of osteoporosis in terms of mortality, long-term disability and decreased quality of life. In the recent years, different techniques have been developed to assess lower limb strength and ultimately fracture risk. Here we examine relationships between two measures of lower limb bone geometry and strength; proximal femoral geometry and tibial peripheral quantitative computed tomography. We studied a sample of 431 women and 488 men aged in the range 59-71 years. The hip structural analysis (HSA) programme was employed to measure the structural geometry of the left hip for each DXA scan obtained using a Hologic QDR 4500 instrument while pQCT measurements of the tibia were obtained using a Stratec 2000 instrument in the same population. We observed strong sex differences in proximal femoral geometry at the narrow neck, intertrochanteric and femoral shaft regions. There were significant (p < 0.001) associations between pQCT-derived measures of bone geometry (tibial width; endocortical diameter and cortical thickness) and bone strength (strength strain index) with each corresponding HSA variable (all p < 0.001) in both men and women. These results demonstrate strong correlations between two different methods of assessment of lower limb bone strength: HSA and pQCT. Validation in prospective cohorts to study associations of each with incident fracture is now indicated.

Skeletal muscle morphology in sarcopenia defined using the EWGSOP criteria: findings from the Hertfordshire Sarcopenia Study (HSS).

BACKGROUND: Sarcopenia is defined as the loss of muscle mass and function with age and is associated with decline in mobility, frailty, falls and mortality. There is considerable interest in understanding the underlying mechanisms. Our aim was to characterise muscle morphology changes associated with sarcopenia among community dwelling older men. METHODS: One hundred and five men aged 68-76 years were recruited to the Hertfordshire Sarcopenia Study (HSS) for detailed characterisation of muscle including measures of muscle mass, strength and function. Muscle tissue was obtained from a biopsy of the vastus lateralis for 99 men and was processed for immunohistochemical studies to determine myofibre distribution and area, capillarisation and satellite cell (SC) density. RESULTS: Six (6 %) men had sarcopenia as defined by the European Working Group on Sarcopenia in Older People (EWGSOP) criteria. These men had lower SC density (1.7 cells/mm(2) vs 3.8 cells/mm(2), p = 0.06) and lower SC/fibre ratio (0.02 vs 0.06, p = 0.06) than men without sarcopenia. Although men with sarcopenia tended to have smaller myofibres and lower capillary to fibre ratio, these relationships were not statistically significant. CONCLUSION: We have shown that there may be altered muscle morphology parameters in older men with sarcopenia. These results have the potential to help identify cell and molecular targets for therapeutic intervention. This work now requires extension to larger studies which also include women.

Cross-sectional associations between different measures of obesity and muscle strength in men and women in a British cohort study.

OBJECTIVES: The relationship between obesity and grip strength, a key indicator of sarcopenia, has been inconsistently reported. We aimed to examine associations between grip strength and both body mass index (BMI), a clinical indicator of total adiposity, and waist circumference (WC), an indicator of central adiposity. DESIGN: Cross-sectional study. SETTING AND PARTICIPANTS: Data collected from 8,441 men and women, aged 48-92 years old, who attended the third health examination of the European Prospective Investigation into Cancer-Norfolk study was used. MEASUREMENTS: Maximum grip strength (Smedley dynamometer), BMI (weight/height2) and WC (measured at the natural waist) were ascertained at a research clinic. The associations between grip strength and adiposity measures were explored using linear regression with adjustment for age, height, social class, physical activity, prevalent disease, smoking status and alcohol intake. RESULTS: Men and women were examined separately and those in the upper quartile of BMI were 2.70kg (95%CI 2.07, 3.33) and 1.46kg (95%CI 1.05, 1.86) stronger respectively than those in the bottom quartile (P trends <0.001). Grip strength also increased weakly with increasing WC. However, including both BMI and WC in the same regression model revealed an inverse association between grip strength and WC, whilst the previously observed association with BMI strengthened. For every 10cm increase in WC, grip strength was 3.56kg (95%CI 3.04, 4.08) lower in men and 1.00kg (95%CI 0.74, 1.24) lower in women. CONCLUSIONS: Larger overall body mass, indicated by higher BMI, is associated with stronger grip strength but high WC, a clinical indicator of central obesity, is associated with lower grip strength. Abdominal fat is the most metabolically active adipose tissue and this provides a clue to potential mechanisms underlying relationships between fat and skeletal muscle. Additionally, it reinforces the recommendation to measure WC in clinical practice, especially when BMI is below obese ranges.