Effect of spironolactone on physical performance in older people with self-reported physical disability

Frontiers in sarcopenia: Advancements in diagnostics, molecular mechanisms, and therapeutic strategies

The onset of sarcopenia is intimately linked with aging, posing significant implications not only for individual patient quality of life but also for the broader societal healthcare framework. Early and accurate identification of sarcopenia and a comprehensive understanding of its mechanistic underpinnings and therapeutic targets paramount to addressing this condition effectively. This review endeavors to present a cohesive overview of recent advancements in sarcopenia research and diagnosis. We initially delve into the contemporary diagnostic criteria, specifically referencing the European Working Group on Sarcopenia in Older People (EWGSOP) 2 and Asian Working Group on Sarcopenia (AWGS) 2019 benchmarks. Additionally, we elucidate comprehensive assessment techniques for muscle strength, quantity, and physical performance, highlighting tools such as grip strength, chair stand test, dual-energy X-ray Absorptiometry (DEXA), bioelectrical impedance analysis (BIA), gait speed, and short physical performance battery (SPPB), while also discussing their inherent advantages and limitations. Such diagnostic advancements pave the way for early identification and unequivocal diagnosis of sarcopenia. Proceeding further, we provide a deep-dive into sarcopenia's pathogenesis, offering a thorough examination of associated signaling pathways like the Myostatin, AMP-activated protein kinase (AMPK), insulin/IGF-1 Signaling (IIS), and the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) pathways. Each pathway's role in sarcopenia mediation is detailed, underscoring potential therapeutic target avenues. From a mechanistic perspective, the review also underscores the pivotal role of mitochondrial dysfunction in sarcopenia, emphasizing elements such as mitochondrial oxidative overload, mitochondrial biogenesis, and mitophagy, and highlighting their therapeutic significance. At last, we capture recent strides made in sarcopenia treatment, ranging from nutritional and exercise interventions to potential pharmacological and supplementation strategies. In sum, this review meticulously synthesizes the latest scientific developments in sarcopenia, aiming to enhance diagnostic precision in clinical practice and provide comprehensive insights into refined mechanistic targets and innovative therapeutic interventions, ultimately contributing to optimized patient care and advancements in the field.

Current understanding and future perspectives on the extraction, structures, and regulation of muscle function of tea pigments

With the aggravating aging of modern society, the sarcopenia-based aging syndrome poses a serious potential threat to the health of the elderly. Natural dietary supplements show great potential to reduce muscle wasting and enhance muscle performance. Tea has been widely recognized for its health-promoting effects. which contains active ingredients such as tea polyphenols, tea pigments, tea polysaccharides, theanine, caffeine, and vitamins. In different tea production processes, the oxidative condensation and microbial transformation of catechins and other natural substances from tea promotes the production of various tea pigments, including theaflavins (TFs), thearubigins (TRs), and theabrownins (TBs). Tea pigments have shown a positive effect on maintaining muscle health. Nevertheless, the relationship between tea pigments and skeletal muscle function has not been comprehensively elucidated. In addition, the numerous research on the extraction and purification of tea pigments is disordered with the limited recent progress due to the complexity of species and molecular structure. In this review, we sort out the strategies for the separation of tea pigments, and discuss the structures of tea pigments. On this basis, the regulation mechanisms of tea pigments on muscle functional were emphasized. This review highlights the current understanding on the extraction methods, molecular structures and regulation mechanisms of muscle function of tea pigments. Furthermore, main limitations and future perspectives are proposed to provide new insights into broadening theoretical research and industrial applications of tea pigments in the future.

MET-PREVENT: metformin to improve physical performance in older people with sarcopenia and physical prefrailty/frailty - protocol for a double-blind, randomised controlled proof-of-concept trial

INTRODUCTION

Skeletal muscle dysfunction is central to both sarcopenia and physical frailty, which are associated with a wide range of adverse outcomes including falls and fractures, longer hospital stays, dependency and the need for care. Resistance training may prevent and treat sarcopenia and physical frailty, but not everyone can or wants to exercise. Finding alternatives is critical to alleviate the burden of adverse outcomes associated with sarcopenia and physical frailty. This trial will provide proof-of-concept evidence as to whether metformin can improve physical performance in older people with sarcopenia and physical prefrailty or frailty.

METHODS AND ANALYSIS

MET-PREVENT is a parallel group, double-blind, placebo-controlled proof-of-concept trial. Trial participants can participate from their own homes, including completing informed consent and screening assessments. Eligible participants with low grip strength or prolonged sit-to-stand time together with slow walk speed will be randomised to either oral metformin hydrochloride 500 mg tablets or matched placebo, taken three times a day for 4 months. The recruitment target is 80 participants from two secondary care hospitals in Newcastle and Gateshead, UK. Local primary care practices will act as participant identification centres. Randomisation will be performed using a web-based minimisation system with a random element, balancing on sex and baseline walk speed. Participants will be followed up for 4 months post-randomisation, with outcomes collected at baseline and 4 months. The primary outcome measure is the four metre walk speed at the 4-month follow-up visit.

ETHICS AND DISSEMINATION

The trial has been approved by the Liverpool NHS Research Ethics Committee (20/NW/0470), the Medicines and Healthcare Regulatory Authority (EudraCT 2020-004023-16) and the UK Health Research Authority (IRAS 275219). Results will be made available to participants, their families, patients with sarcopenia, the public, regional and national clinical teams, and the international scientific community.

TRIAL REGISTRATION NUMBER

ISRCTN29932357.

Effect of perindopril or leucine on physical performance in older people with sarcopenia: the LACE randomized controlled trial

BACKGROUND

This trial aimed to determine the efficacy of leucine and/or perindopril in improving physical function in older people with sarcopenia.

METHODS

Placebo-controlled, parallel group, double-blind, randomized two-by-two factorial trial. We recruited adults aged ≥ 70 years with sarcopenia, defined as low gait speed (<0.8 m/s on 4 m walk) and/or low handgrip strength (women < 20 kg, men < 30 kg) plus low muscle mass (using sex and body mass index category-specific thresholds derived from normative UK BioBank data) from 14 UK centres. Eligible participants were randomized to perindopril 4 mg or placebo, and to oral leucine powder 2.5 g or placebo thrice daily. The primary outcome was the between-group difference in the short physical performance battery (SPPB) score over 12-month follow-up by repeated-measures mixed models. Results were combined with existing systematic reviews using random-effects meta-analysis to derive summary estimates of treatment efficacy.

RESULTS

We screened 320 people and randomized 145 participants compared with an original target of 440 participants. For perindopril [n = 73, mean age 79 (SD 6), female sex 39 (53%), mean SPPB 7.1 (SD 2.3)] versus no perindopril [n = 72, mean age 79 (SD 6), female sex 39 (54%), mean SPPB 6.9 (SD 2.4)], median adherence to perindopril was lower (76% vs. 96%; P < 0.001). Perindopril did not improve the primary outcome [adjusted treatment effect -0.1 points (95%CI -1.2 to 1.0), P = 0.89]. No significant treatment benefit was seen for any secondary outcome including muscle mass [adjusted treatment effect -0.4 kg (95%CI -1.1 to 0.3), P = 0.27]. More adverse events occurred in the perindopril group (218 vs. 165), but falls rates were similar. For leucine [n = 72, mean age 78 (SD 6), female sex 38 (53%), mean SPPB 7.0 (SD 2.1)] versus no leucine [n = 72, mean age 79 (SD 6), female sex 40 (55%), mean SPPB 7.0 (SD 2.5)], median adherence was the same in both groups (76% vs. 76%; P = 0.99). Leucine did not improve the primary outcome [adjusted treatment effect 0.1 point (95%CI -1.0 to 1.1), P = 0.90]. No significant treatment benefit was seen for any secondary outcome including muscle mass [adjusted treatment effect -0.3 kg (95%CI -1.0 to 0.4), P = 0.47]. Meta-analysis of angiotensin converting enzyme inhibitor/angiotensin receptor blocker trials showed no clinically important treatment effect for the SPPB [between-group difference -0.1 points (95%CI -0.4 to 0.2)].

CONCLUSIONS

Neither perindopril nor leucine improved physical performance or muscle mass in this trial; meta-analysis did not find evidence of efficacy of either ACE inhibitors or leucine as treatments to improve physical performance.

Adjusted Indirect and Mixed Comparisons of Interventions for the Patient-Reported Outcomes Measures (PROMs) of Disabled Adults: A Systematic Review and Network Meta-Analysis

This systematic review adopted the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Statement (PRISMA) guidelines and used the method of network meta-analysis to compare the effects of different types of interventions from different perspectives which were abilities of daily life activity, psychological health, social functioning, and overall life quality. The eligibility criteria were: (1) Participants were adults above 18 years old with disabilities; (2) Interventions could be classified into active exercise, passive therapy, psychological education, psychosocial support program, multi-disciplinary program, and usual care; (3) Outcomes should be the patient-reported outcome measures (PROMs) that could be classified into abilities of daily life activity, psychological health, social functioning, and overall life quality; (4) Randomized designed and published in English. The keywords and their search field were: (1) “people with disabilities/disability”, “disabled”, “handicapped”, or “disable people” in titles or abstracts; (2) AND “randomized” or “randomised” in titles or abstracts; (3) NOT “design”, “protocol”, or “review” in titles. After searching in databases of Medline (EBSCO), PubMed, CINAHL, and Ovid, 16 studies were included. As a result, active exercise and passive therapy are most likely to be the best interventions for overall life quality, psychological education and passive therapy are most likely to be the best interventions for abilities of daily life activity, and psychosocial support programs are most likely to be the best intervention for psychological health and social functioning.

Adrenal stress hormone action in skeletal muscle during exercise training: An old dog with new tricks?

Exercise is a key component of a healthy lifestyle as it helps maintain a healthy body weight and reduces the risk of various morbidities and co-morbidities. Exercise is an acute physiological stress that initiates a multitude of processes that attempt to restore physiological homeostasis and promote adaptation. A component of the stress response to exercise is the rapid release of hormones from the adrenal gland including glucocorticoids, the catecholamines and aldosterone. While each hormone targets several tissues throughout the body, skeletal muscle is of interest as it is central to physical function and various metabolic processes. Indeed, adrenal stress hormones have been shown to elicit specific performance benefits on the muscle. However, how the acute, short-lived release of these stress hormones during exercise influences adaptations of skeletal muscle to long-term training remains largely unknown. Thus, the objective of this review was to briefly highlight the known impact of adrenal stress hormones on skeletal muscle metabolism and function (Old Dog), and critically examine the current evidence supporting a role for these endogenous hormones in mediating long-term training adaptations in skeletal muscle (New Tricks).

Muscle Wasting and Sarcopenia in Heart Failure-The Current State of Science

Sarcopenia is primarily characterized by skeletal muscle disturbances such as loss of muscle mass, quality, strength, and physical performance. It is commonly seen in elderly patients with chronic diseases. The prevalence of sarcopenia in chronic heart failure (HF) patients amounts to up to 20% and may progress into cardiac cachexia. Muscle wasting is a strong predictor of frailty and reduced survival in HF patients. Despite many different techniques and clinical tests, there is still no broadly available gold standard for the diagnosis of sarcopenia. Resistance exercise and nutritional supplementation represent the currently most used strategies against wasting disorders. Ongoing research is investigating skeletal muscle mitochondrial dysfunction as a new possible target for pharmacological compounds. Novel agents such as synthetic ghrelin and selective androgen receptor modulators (SARMs) seem promising in counteracting muscle abnormalities but their effectiveness in HF patients has not been assessed yet. In the last decades, many advances have been accomplished but sarcopenia remains an underdiagnosed pathology and more efforts are needed to find an efficacious therapeutic plan. The purpose of this review is to illustrate the current knowledge in terms of pathogenesis, diagnosis, and treatment of sarcopenia in order to provide a better understanding of wasting disorders occurring in chronic heart failure.

Current evidence on the impact of medication optimization or pharmacological interventions on frailty or aspects of frailty: a systematic review of randomized controlled trials

Background

Frailty and adverse drug effects are linked in the fact that polypharmacy is correlated with the severity of frailty; however, a causal relation has not been proven in older people with clinically manifest frailty.

Methods

A literature search was performed in Medline to detect prospective randomized controlled trials (RCTs) testing the effects of pharmacological interventions or medication optimization in older frail adults on comprehensive frailty scores or partial aspects of frailty that were published from January 1998 to October 2019.

Results

Twenty-five studies were identified, 4 on comprehensive frailty scores and 21 on aspects of frailty. Two trials on comprehensive frailty scores showed positive results on frailty although the contribution of medication review in a multidimensional approach was unclear. In the studies on aspects related to frailty, ten individual drug interventions showed improvement in physical performance, muscle strength or body composition utilizing alfacalcidol, teriparatide, piroxicam, testosterone, recombinant human chorionic gonadotropin, or capromorelin. There were no studies examining negative effects of drugs on frailty.

Conclusion

So far, data on a causal relationship between drugs and frailty are inconclusive or related to single-drug interventions on partial aspects of frailty. There is a clear need for RCTs on this topic that should be based on a comprehensive, internationally consistent and thus reproducible concept of frailty assessment.

Electronic supplementary material

The online version of this article (10.1007/s00228-020-02951-8) contains supplementary material, which is available to authorized users.

Sodium bicarbonate to improve physical function in patients over 60 years with advanced chronic kidney disease: the BiCARB RCT

BACKGROUND

Advanced chronic kidney disease is common in older people and is frequently accompanied by metabolic acidosis. Oral sodium bicarbonate is used to treat this acidosis, but evidence is lacking on whether or not this provides a net gain in health or quality of life for older people.

OBJECTIVES

The objectives were to determine whether or not oral bicarbonate therapy improves physical function, quality of life, markers of renal function, bone turnover and vascular health compared with placebo in older people with chronic kidney disease and mild acidosis; to assess the safety of oral bicarbonate; and to establish whether or not oral bicarbonate therapy is cost-effective in this setting.

DESIGN

A parallel-group, double-blind, placebo-controlled randomised trial.

SETTING

The setting was nephrology and geriatric medicine outpatient departments in 27 UK hospitals.

PARTICIPANTS

Participants were adults aged ≥ 60 years with advanced chronic kidney disease (glomerular filtration rate category 4 or 5, not on dialysis) with a serum bicarbonate concentration of < 22 mmol/l.

INTERVENTIONS

Eligible participants were randomised 1 : 1 to oral sodium bicarbonate or matching placebo. Dosing started at 500 mg three times daily, increasing to 1 g three times daily if the serum bicarbonate concentration was < 22 mmol/l at 3 months.

MAIN OUTCOME MEASURES

The primary outcome was the between-group difference in the Short Physical Performance Battery score at 12 months, adjusted for baseline. Other outcome measures included generic and disease-specific health-related quality of life, anthropometry, 6-minute walk speed, grip strength, renal function, markers of bone turnover, blood pressure and brain natriuretic peptide. All adverse events were recorded, including commencement of renal replacement therapy. For the health economic analysis, the incremental cost per quality-adjusted life-year was the main outcome.

RESULTS

In total, 300 participants were randomised, 152 to bicarbonate and 148 to placebo. The mean age of participants was 74 years and 86 (29%) were female. Adherence to study medication was 73% in both groups. A total of 220 (73%) participants were assessed at the 12-month visit. No significant treatment effect was evident for the primary outcome of the between-group difference in the Short Physical Performance Battery score at 12 months (-0.4 points, 95% confidence interval -0.9 to 0.1 points; p = 0.15). No significant treatment benefit was seen for any of the secondary outcomes. Adverse events were more frequent in the bicarbonate arm (457 vs. 400). Time to commencement of renal replacement therapy was similar in both groups (hazard ratio 1.22, 95% confidence interval 0.74 to 2.02; p = 0.43). Health economic analysis showed higher costs and lower quality of life in the bicarbonate arm at 1 year, with additional costs of £564 (95% confidence interval £88 to £1154) and a quality-adjusted life-year difference of -0.05 (95% confidence interval -0.08 to -0.01); placebo dominated bicarbonate under all sensitivity analyses for incremental cost-effectiveness.

LIMITATIONS

The trial population was predominantly white and male, limiting generalisability. The increment in serum bicarbonate concentrations achieved was small and a benefit from larger doses of bicarbonate cannot be excluded.

CONCLUSIONS

Oral sodium bicarbonate did not improve a range of health measures in people aged ≥ 60 years with chronic kidney disease category 4 or 5 and mild acidosis, and is unlikely to be cost-effective for use in the NHS in this patient group. Once other current trials of bicarbonate therapy in chronic kidney disease are complete, an individual participant meta-analysis would be helpful to determine which subgroups, if any, are more likely to benefit and which treatment regimens are more beneficial.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN09486651 and EudraCT 2011-005271-16. The systematic review is registered as PROSPERO CRD42018112908.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 24, No. 27. See the NIHR Journals Library website for further project information.

Sarcopenia: A Contemporary Health Problem among Older Adult Populations

Sarcopenia, a geriatric disease characterized by a progressive loss of skeletal muscle mass and loss of muscle function, constitutes a rising, often undiagnosed health problem. Its prevalence in the elderly population is largely considered variable, as it ranges from 5% to 50% depending on gender, age, pathological conditions as well as diagnostic criteria. There is no one unified approach of treatment or assessment, which makes sarcopenia even harder to assess. There is a pressing need to provide better diagnosis, diagnostics, prevention, and individualized health care. Physical activity and nutrition are the main studied ways to prevent sarcopenia, and they also offer better outcomes. This review aims to report the prevalence of sarcopenia in older adults, its etiology, prevention, and treatment techniques.

Clinical and cost-effectiveness of oral sodium bicarbonate therapy for older patients with chronic kidney disease and low-grade acidosis (BiCARB): a pragmatic randomised, double-blind, placebo-controlled trial

BACKGROUND

Chronic kidney disease with metabolic acidosis is common in older people, but the effectiveness of oral sodium bicarbonate therapy in this group is unclear. We tested whether oral sodium bicarbonate provides net health benefit for older people with advanced chronic kidney disease and serum bicarbonate concentrations < 22 mmol/L.

METHODS

Pragmatic multicentre, parallel group, double-blind, placebo-controlled randomised trial. We recruited adults aged ≥ 60 years with estimated glomerular filtration rate of < 30 mL/min/1.73 m², not receiving dialysis, with serum bicarbonate concentration < 22 mmol/L, from 27 nephrology and geriatric medicine departments in the UK. Participants received oral sodium bicarbonate (up to 3 g/day) or matching placebo given for up to 2 years, randomised in a 1:1 ratio. The primary outcome was between-group difference in the Short Physical Performance Battery (SPPB) at 12 months, adjusted for baseline values, analysed by intention to treat. Secondary outcomes included generic and disease-specific quality of life (EQ-5D and KDQoL tools), anthropometry, renal function, walk distance, blood pressure, bone and vascular health markers, and incremental cost per quality-adjusted life year gained.

RESULTS

We randomised 300 participants between May 2013 and February 2017, mean age 74 years, 86 (29%) female. At 12 months, 116/152 (76%) participants allocated to bicarbonate and 104/148 (70%) allocated to placebo were assessed; primary outcome data were available for 187 participants. We found no significant treatment effect for the SPPB: bicarbonate arm 8.3 (SD 2.5) points, placebo arm 8.8 (SD 2.2) and adjusted treatment effect - 0.4 (95% CI - 0.9 to 0.1, p = 0.15). We found no significant treatment effect for glomerular filtration rate (0.6 mL/min/1.73 m², 95% CI - 0.8 to 2.0, p = 0.39). The bicarbonate arm showed higher costs and lower quality of life as measured by the EQ-5D-3L tool over 1 year (£564 [95% CI £88 to £1154]); placebo dominated bicarbonate under all sensitivity analyses. Adverse events were more frequent in those randomised to bicarbonate (457 versus 400).

CONCLUSIONS

Oral sodium bicarbonate did not improve physical function or renal function, increased adverse events and is unlikely to be cost-effective for use by the UK NHS for this patient group.

TRIAL REGISTRATION

European Clinical Trials Database (2011-005271-16) and ISRCTN09486651; registered 17 February 2012.

Spironolactone for People Age 70 Years and Older With Osteoarthritic Knee Pain: A Proof-of-Concept Trial

Objective

To determine whether spironolactone could benefit older people with osteoarthritis (OA), based on a previous study showing that spironolactone improved quality of life.

Methods

This parallel‐group, randomized, placebo‐controlled, double‐blind trial randomized community‐dwelling people ages ≥70 years with symptomatic knee OA to 12 weeks of 25 mg daily oral spironolactone or matching placebo. The primary outcome was between‐group difference in change in Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain subscale scores. Secondary outcomes included WOMAC stiffness and physical function subscores, EuroQol 5‐domain (EQ‐5D) 3L score, and mechanistic markers. Analysis was by intent to treat, using mixed‐model regression, adjusting for baseline values of test variables.

Results

A total of 421 people had eligibility assessed, and 86 were randomized. Mean ± SD age was 77 ± 5 years and 53 of 86 (62%) were women. Adherence to study medication was 99%, and all participants completed the 12‐week assessment. No significant improvement was seen in the WOMAC pain score (adjusted treatment effect 0.5 points [95% confidence interval (95% CI) − 0.3, 1.3]; P = 0.19). No improvement was seen in WOMAC stiffness score (0.2 points [95% CI −0.6, 1.1]; P = 0.58), WOMAC physical function score (0.0 points [95% CI −0.7, 0.8]; P = 0.98), or EQ‐5D 3L score (0.04 points [95% CI −0.04, 0.12]; P = 0.34). Cortisol, matrix metalloproteinase 3, and urinary C‐telopeptide of type II collagen were not significantly different between groups. More minor adverse events were noted in the spironolactone group (47 versus 32), but no increase in death or hospitalization was evident.

Conclusion

Spironolactone did not improve symptoms, physical function, or health‐related quality of life in older people with knee OA.

Frailty in Advanced Heart Failure: A Consequence of Aging or a Separate Entity?

There are over 5 million Americans with heart failure (HF), the majority of whom are over age 65. Frailty is a systemic syndrome associated with aging that produces subclinical dysfunction across multiple organ systems and leads to an increased risk for morbidity and mortality. The prevalence of frailty is about 10% in community-dwelling elderly and 20% in those with advanced HF, and increases in both cohorts with age. Yet the relationship between the primary frailty of aging and frailty secondary to HF remains poorly defined. Whether the frailty of these two populations share similar etiologies or exist as separate entities is unknown. Teasing apart potential molecular, cellular, and functional differences between the frailty of aging and that of advanced HF has implications for risk stratification, quality of life, and pharmacological and therapeutic interventions for advanced HF patients.

The Right Ventricular Function After Left Ventricular Assist Device (RVF-LVAD) study: rationale and preliminary results

AIMS

Despite improved outcomes and lower right ventricular failure (RVF) rates with continuous-flow left ventricular assist devices (LVADs), RVF still occurs in 20-40% of LVAD recipients and leads to worse clinical and patient-centred outcomes and higher utilization of healthcare resources. Preoperative quantification of RV function with echocardiography has only recently been considered for RVF prediction, and RV mechanics have not been prospectively evaluated.

METHODS AND RESULTS

In this single-centre prospective cohort study, we plan to enroll a total of 120 LVAD candidates to evaluate standard and mechanics-based echocardiographic measures of RV function, obtained within 7 days of planned LVAD surgery, for prediction of (i) RVF within 90 days; (ii) quality of life (QoL) at 90 days; and (iii) RV function recovery at 90 days post-LVAD. Our primary hypothesis is that an RV echocardiographic score will predict RVF with clinically relevant discrimination (C >0.85) and positive and negative predictive values (>80%). Our secondary hypothesis is that the RV score will predict QoL and RV recovery by 90 days. We expect that RV mechanics will provide incremental prognostic information for these outcomes. The preliminary results of an interim analysis are encouraging.

CONCLUSION

The results of this study may help improve LVAD outcomes and reduce resource utilization by facilitating shared decision-making and selection for LVAD implantation, provide insights into RV function recovery, and potentially inform reassessment of LVAD timing in patients at high risk for RVF.

Sarcopenia

Sarcopenia, the loss of muscle mass and function with age, is highly relevant to clinical practice as it has been associated with a wide range of ageing outcomes including disability and shorter survival times. As such it is now a major focus for research and drug discovery. There has been recent progress in the development of consensus definitions for the diagnosis of sarcopenia, taking the form of measurements of muscle mass and strength or physical performance. These definitions form potential inclusion criteria for use in trials, although the optimum choice of outcome measures is less clear. Prevalence estimates using these new definitions vary, although they suggest that sarcopenia is a common (approximately 13% from one study) clinical problem in older people. A range of lifestyle factors have been investigated in regard to the development of this condition, and progressive resistance training is the most well-established intervention so far. There is also marked research interest in the role of diet, although so far the value of supplementation is less clear. Other potential treatments for sarcopenia include the angiotensin-converting enzyme inhibitors, with some evidence that they can improve physical performance in older people. Future research directions include an increased understanding of the molecular and cellular mechanisms of sarcopenia and the use of a life course approach to explore the possibility of earlier intervention and prevention.