Cytokines, insulin-like growth factor 1, sarcopenia, and mortality in very old community-dwelling men and women: the Framingham Heart Study

Sarcopenia Associated with Chronic Obstructive Pulmonary Disease

Sarcopenia is frequently associated with chronic diseases such as chronic obstructive pulmonary disease (COPD) and cancer. COPD, which is characterized by an irreversible airflow limitation, exacerbates respiratory distress as the disease progresses. The prevalence of sarcopenia in stable COPD was reported to be 15% to 25% in previous foreign studies and 25% in a Korean study. As the amount of activity decreases, muscle mass decreases and eventually oxygen cannot be used effectively, resulting in a vicious cycle of deterioration of exercise capacity. Deconditioning due to decreased activity is a major cause of limb muscle dysfunction in patients with COPD. In these patients, the factors that decrease muscle strength and endurance include chronic inflammation, oxidative stress, inactivity, hypoxemia, hormone abnormality, deficits of nutrients such as protein and vitamin D, and the use of systemic corticosteroid. Therefore, treatment and management should either inhibit this process or should be directed toward supplementing the deficiency, such as with exercise, nutritional support, and medications and supplements. The relationship between sarcopenia and COPD is increasingly being reported, with some overlap in clinical features and treatments. We are fascinated to be able to diagnose 2 diseases through similar physical performance tests and to improve both diseases using the same treatment such as exercise. Therefore, this review summarizes the clinical relevance and integrative management of the 2 diseases.

Bioimpedance analysis and physical functioning as mortality indicators among older sarcopenic people

OBJECTIVES

To assess the prognostic significance of various characteristics and measurements of sarcopenia and physical functioning on all-cause mortality among home-dwelling older people with or at-risk of sarcopenia.

DESIGN

Cross-sectional and longitudinal analyses.

SETTING

Porvoo sarcopenia trial in open care.

PARTICIPANTS

Community-dwelling people aged 75 and older (N = 428, of which 182 were re-examined at one year) with four years of follow-up.

MEASUREMENTS

Body mass index (BMI), physical functioning (physical component of the RAND-36) and physical performance tests (Short Physical Performance Battery (SPPB)), hand grip strength, walking speed, Charlson Comorbity Index, bioimpedance-based surrogates for muscle mass: Single Frequency Skeletal Muscle Index (SF-SMI), and Calf Intracellular Resistance Skeletal Muscle Index (CRi-SMI). Date of death was retrieved from central registers. Survival analyses were performed using Life-Table analyses and Cox models.

RESULTS

Most test variables (except BMI) were associated with four-year mortality in a dose-dependent fashion. After controlling for age, gender and co-morbidity, physical performance and functioning (both SPPB and RAND-36), muscle strength (hand grip strength) and CRi-SMI appeared to be independent mortality risk indicators (p < 0.001) whereas SF-SMI was not. When CRi-SMI values were grouped by gender-specific cut-off points, the probability of surviving for four years decreased by 66% among the older people with low CRi-SMI (HR = 0.34, 95%CI 0.15-0.78, p = 0.011). When low CRi-SMI was further controlled for SPPB, the prognostic significance remained significant (HR = 0.55, 95%CI 0.33-0.92, p = 0.021). After controlling for age, gender, comorbidity, and CRi-SMI, the physical component of the RAND-36 (p = 0.007), SPPB (p < 0,001) and hand grip strength (p = 0.009) remained significant mortality predictors. Twelve-month changes were similarly associated with all-cause mortality during the follow-up period.

CONCLUSION

CRi-SMI, muscle strength, physical performance and physical functioning are each strong independent predictors of all-cause mortality among home-dwelling older people. Compared to these indicators, BMI seemed to be clearly inferior. Of two bioimpedance-based muscle indices, CRi SMI was better predictor of mortality than SF-SMI. In this regard, muscle mass, muscle strength and physical performance are all suitable targets for the prevention of sarcopenia-related over-mortality.

Frailty, Inflammatory Markers, and Waitlist Mortality Among Patients With End-stage Renal Disease in a Prospective Cohort Study

BACKGROUND

Among community-dwelling older adults, frailty is associated with heightened markers of inflammation and subsequent mortality. Although frailty is common among end-stage renal disease (ESRD) patients, the role of frailty and markers of inflammation in this population remains unclear. We quantified these associations in patients on the kidney transplant waitlist and tested whether frailty and/or markers of inflammation improve waitlist mortality risk prediction.

METHODS

We studied 1975 ESRD patients on the kidney transplant waitlist (November 1, 2009, to February 28, 2017) in a multi-center cohort study of frailty. Serum inflammatory markers (interleukin-6 [IL-6], soluble tumor necrosis factor-α receptor-1 [sTNFR1], and C-reactive protein [CRP]) were analyzed in 605 of these participants; we calculated the inflammatory index score using IL-6 and sTNFR1. We compared the C-statistic of an established registry-based prediction model for waitlist mortality adding frailty and/or inflammatory markers (1 SD change in log IL-6, sTNFR1, CRP, or inflammatory index).

RESULTS

The registry-based model had moderate predictive ability (c-statistic = 0.655). Frailty was associated with increased mortality (2.19; 95% confidence interval [CI], 1.26-3.79) but did not improve risk prediction (c-statistic = 0.646; P = 0.65). Like frailty, IL-6 (2.13; 95% CI, 1.41-3.22), sTNFR1 (1.70; 95% CI, 1.12-2.59), CRP (1.68; 95% CI, 1.06-2.67), and the inflammatory index (2.09; 95% CI, 1.38-3.16) were associated with increased mortality risk; unlike frailty, adding IL-6 (c-statistic = 0.777; P = 0.02), CRP (c-statistic = 0.728; P = 0.02), or inflammatory index (c-statistic = 0.777; P = 0.02) substantially improved mortality risk prediction.

CONCLUSIONS

Frailty and markers of inflammation were associated with increased waitlist mortality risk, but only markers of inflammation significantly improved ESRD risk prediction. These findings help clarify the accelerated aging physiology of ESRD and highlight easy-to-measure markers of increased waitlist mortality risk.

Extranuclear DNA accumulates in aged cells and contributes to senescence and inflammation

Systemic inflammation is central to aging‐related conditions. However, the intrinsic factors that induce inflammation are not well understood. We previously identified a cell‐autonomous pathway through which damaged nuclear DNA is trafficked to the cytosol where it activates innate cytosolic DNA sensors that trigger inflammation. These results led us to hypothesize that DNA released after cumulative damage contributes to persistent inflammation in aging cells through a similar mechanism. Consistent with this notion, we found that older cells harbored higher levels of extranuclear DNA compared to younger cells. Extranuclear DNA was exported by a leptomycin B‐sensitive process, degraded through the autophagosome–lysosomal pathway and triggered innate immune responses through the DNA‐sensing cGAS‐STING pathway. Patient cells from the aging diseases ataxia and progeria also displayed extranuclear DNA accumulation, increased pIRF3 and pTBK1, and STING‐dependent p16 expression. Removing extranuclear DNA in old cells using DNASE2A reduced innate immune responses and senescence‐associated (SA) β‐gal enzyme activity. Cells and tissues of Dnase2a^−/− mice with defective DNA degradation exhibited slower growth, higher activity of β‐gal, or increased expression of HP‐1β and p16 proteins, while Dnase2a^−/−;Sting^−/− cells and tissues were rescued from these phenotypes, supporting a role for extranuclear DNA in senescence. We hypothesize a direct role for excess DNA in aging‐related inflammation and in replicative senescence, and propose DNA degradation as a therapeutic approach to remove intrinsic DNA and revert inflammation associated with aging.

The biology of frailty in humans and animals: Understanding frailty and promoting translation

Frailty is a state of high vulnerability to adverse health outcomes. This concept is used to explain the heterogeneity in rates of aging in people of the same age. Frailty has important clinical implications, because even minor stressors can lead to adverse outcomes, including death, in frail individuals. Although frailty mechanisms are not well understood, advances in our ability to qualify frailty have encouraged efforts in this area. Quantification of frailty with both "frailty phenotype" and "frailty index" approaches has begun to highlight putative frailty mechanisms and new animal models of frailty are inspiring preclinical research. These models either adapt frailty phenotype and frailty index tools for use in animals or they use genetically manipulated mice that mimic conditions seen in frailty (eg, inflammation, sarcopenia, weakness). This review: describes commonly used tools to quantify frailty clinically, discusses potential frailty mechanisms, and describes animal models of frailty. It also highlights how these models have been used to explore frailty mechanisms and potential frailty interventions, including pharmacological treatments, diet, and exercise. These exciting new developments in the field have the potential to facilitate translational research, improve our understanding of mechanisms of frailty, and help develop new interventions to mitigate frailty in our aging population.

Association between sarcopenia and erectile dysfunction in males with type II diabetes mellitus

BACKGROUND

The prevalence rates for both sarcopenia and erectile dysfunction (ED) gradually increase in middle-aged and elderly diabetic male population and they impair physical functioning, sexual functioning, and quality of life. The aim of the present study was to evaluate the sarcopenia in patients with diabetic ED.

METHODS

The study included 98 male patients with type II diabetes mellitus (DM) aged 18-80 years. Blood chemistry and hormone levels were obtained. The International Index of Erectile Function (IIEF-5) questionnaire was administered to the patients. The patients were divided into three groups according to the IIEF-5 score; a score of 5-10 points indicated severe ED, a score of 11-20 indicated moderate ED, and a score of 21-25 points indicated no ED. The muscle mass, handgrip strength, timed up and go test, upper mid-arm circumference, calf circumference, and body mass index were obtained. The statistical analysis was performed using MedCalc Statistical Software version 12.7.7. All parameters were compared between the three groups.

RESULTS

Of 98 patients included in the study, 84 patients had severe sarcopenia, 13 had moderate sarcopenia, while only one patient had normal muscle mass. The mean age was 56.59 ± 11.46 years. When patients were divided into three groups according to IIEF-5 score, 38 had severe ED, 39 had moderate ED, and 21 had no ED. There was a significant difference between the three groups in terms of handgrip strength, timed up and go test scores, upper mid-arm circumference, and calf circumference (p < .05 for all).

CONCLUSIONS

Although muscle mass remains unchanged, muscle strength and physical performance decrease in diabetic ED patients. Diabetic patients with severe and moderate ED have lower muscle strength and physical performance.

Sarcopenic obesity can be negatively associated with active physical activity and adequate intake of some nutrients in Korean elderly: Findings from the Korea National Health and Nutrition Examination Survey (2008-2011)

BACKGROUND/OBJECTIVES

The aim of this study was to analyze the factors related to sarcopenic obesity among the elderly in South Korea.

SUBJECTS/METHODS

A total of 3,367 elderly (≥ 65 years) from the Korea National Health and Nutrition Examination Survey (2008–2011) were included in this analysis. The subjects were assessed to determine their sarcopenia and obesity status. Sarcopenia was assessed by determining their appendicular skeletal muscle mass (ASM). Obesity was defined by the waist circumference. An association of sarcopenic obesity and the related factors was analyzed using multiple logistic regression models.

RESULTS

The risk of sarcopenic obesity of the subjects was decreased by active physical activity. After adjusting for age, smoking, and alcohol consumption, the risk of sarcopenic obesity in men of the highest level group (Q4) decreased by 45% (OR = 0.550, 95% CI = 0.334–0.905, P trend 0.018) compared to that in the reference group (Q1). Among the women, the risk of sarcopenic obesity in the Q3 and Q4 groups decreased by 29.0% (OR = 0.710, 95% CI = 0.512–0,984) and 56.7% (OR = 0.433, 95% CI = 0.281–0.668), respectively, compared to that in the Q1 group (P trend < 0.001). The mean daily energy intake was higher in the non-sarcopenia group than in the sarcopenia group. The risk of sarcopenic obesity in subjects not meeting the recommended intakes of energy, riboflavin, and vitamin C increased significantly by 25.4%, and 36.6%, and 32.6%, respectively, compared to that in the subjects meeting the recommended nutrient intake.

CONCLUSION

Active physical activity as well as an adequate intake of energy and some vitamins might be negatively associated with the development of sarcopenia and sarcopenic obesity in the elderly.

Predictors of presarcopenia in community-dwelling older adults: A 5-year longitudinal study

Objectives: Sarcopenia is an aging-induced decrease in muscle mass that increases frailty and fall in elderly people. Presarcopenia corresponds to the preliminary stage of sarcopenia. The purpose of this prospective study is to examine predictors of presarcopenia in health screening.Methods: The subjects were 124 community residents aged ≥60 years (55 males, 69 females, average age 70.2 years) who attended local government health checkups in 2010 and 2015, as part of the Yakumo study, and did not have presarcopenia in 2010. Body mass index (BMI), waist and hip circumferences, grip strength, bone mineral density (BMD), 10-m gait time, back muscle strength, and stride length were measured. Presarcopenia was defined using the appendicular skeletal muscle index (arm and leg skeletal muscle mass/height²).Results: The prevalences of presarcopenia in 2015 in males and females were 21.8% (12/55) and 30.4% (21/69), respectively. BMI, grip strength, BMD, back muscle strength, and osteoporosis deteriorated significantly more in the pre-sarcopenia group (n = 33) compared with controls (n = 91; no presarcopenia in 2015). In multivariate analysis, osteoporosis (OR 3.12, 95% CI 1.07-9.09; p < .05) was significantly associated with presarcopenia after 5 years.Conclusions: Establishment of risk factors for future pre-sarcopenia may allow development of evidence-based prevention strategies for this condition.

Serum Myostatin and IGF-1 as Gender-Specific Biomarkers of Frailty and Low Muscle Mass in Community-Dwelling Older Adults

OBJECTIVES

(i) To investigate serum myostatin (absolute and normalized for total body lean mass (TBLM)) and IGF-1 as biomarkers of frailty and low relative appendicular skeletal muscle mass (RASM) in older adults, and; (ii) to examine gender differences in the association of serum myostatin and IGF-1 levels with frailty and low RASM.

DESIGN

Cross-sectional study.

SETTING

The "Longitudinal Assessment of Biomarkers for characterization of early Sarcopenia and predicting frailty and functional decline in community-dwelling Asian older adults Study" (GERI-LABS) study in Singapore.

PARTICIPANTS

200 subjects aged 50 years and older residing in the community.

MEASUREMENTS

Frailty was assessed using the modified Fried criteria. Low RASM was defined using cutoffs for height-adjusted appendicular skeletal muscle mass measured by dual-energy X-ray absorptiometry as recommended by the Asian Working Group for Sarcopenia. Comorbidities, cognitive and functional performance, physical activity and nutritional status were assessed. Blood samples collected included serum myostatin, insulin-like growth factor 1 (IGF-1) and markers of inflammation (total white cell count, CRP, IL-6 and TNFaR1). Subjects were classified into 4 groups: Frail/Prefrail with low RASM (Frail/Low RASM), Frail/Prefrail with normal RASM (Frail/Normal RASM), Robust with low RASM (Robust/Low RASM) and Robust with normal RASM (Robust/Normal RASM).

RESULTS

63 (32%) subjects were classified as Frail/Low RASM, 53 (27%) Frail/Normal RASM, 28 (14%) Robust/Low RASM and 56 (28%) Robust/Normal RASM respectively. Frail/Low RASM subjects were older and had lower BMI compared to Frail/Normal RASM and robust subjects. Mean (SE) normalized myostatin levels were higher in Frail/Low RASM compared to Frail/Normal RASM subjects (1.0 (0.04) versus 0.84 (0.05) ng/ml/kg, P=0.01). Median (IQR) IGF-1 level was lower amongst Frail/Low RASM subjects compared to Frail/Normal RASM subjects (102.3, (77.7, 102.5) vs 119.7 (82.7, 146.0) ng/ml, P=0.046). No differences in myostatin or IGF-1 were observed among robust individuals with or without low muscle mass. In adjusted multinomial logistic regression models with Robust/Normal RASM as the reference group, myostatin (P=0.05) and IGF-1 (P=0.043) were associated with Frail/Low RASM status in the whole cohort. When stratified by gender, myostatin was significantly associated with Frail/Low RASM status in men only (P=0.03). In women, serum IGF-1 was associated with Frail/Low RASM status (P=0.046), but not myostatin (P=0.53).

CONCLUSION

Serum myostatin, normalized for TBLM in men and IGF-1 in women are potential biomarkers for frail individuals with low RASM, and may identify a target group for intervention.

The association between self-rated health and high-sensitivity C-reactive protein level: a cross-sectional and 5-year longitudinal study

Background

Although self-rated health (SRH) independently predicts mortality, the biological background of this association remains unexplained. This study aimed to examine the association between SRH and serum high-sensitivity C-reactive protein (hsCRP) level.

Methods

Subjects were 899 participants aged 35–69 years (237 men and 662 women) in the Daiko Study, part of the Japan Multi-Institutional Collaborative Cohort Study. They were enrolled from 2008 to 2010. Of the subjects, 666 participated in a second survey 5 years later. Lifestyle factors and SRH were assessed using a self-administered questionnaire. Serum hsCRP level was measured using a latex-enhanced immunonephelometric assay. The association between SRH and serum hsCRP level was evaluated using a general linear model with covariates. We further longitudinally investigated whether higher serum hsCRP level at baseline predicts poor SRH after 5 years using an unconditional logistic regression model.

Results

A higher serum hsCRP level was significantly associated with poor SRH at baseline after adjusting for covariates (p for trend = 0.023). The age- and sex-adjusted odds ratio and 95% confidence interval (CI) for poor SRH after 5 years was 1.45 (95% CI: 0.76–2.78) for the highest tertile compared with the lowest tertile of serum hsCRP level at baseline with a significant linear trend (p for trend = 0.033), although the risk increase disappeared after adjustment for other covariates.

Conclusions

The present study demonstrated that poor SRH is cross-sectionally associated with higher serum hsCRP level. However, the longitudinal data did not support the relationship between serum hsCRP level at baseline and future SRH. Further longitudinal studies that include data on mortality and multiple inflammatory markers are warranted to elucidate the possible role of low-grade inflammation in the association between SRH and mortality risk.

Insulin-Like Growth Factor-1 in Acute Ischemic Stroke

Background

Cerebrovascular ischemic stroke is highly prevalent in the general population and is considered one of the frequent causes of mortality and disability. Insulin-like growth factor-1 (IGF-1) is recognized as an important neuro-protective factor against cerebral vascular ischemic insult.

Aim of the work

To study the relationship between serum IGF-1 levels and acute ischemic stroke (AIS) in the Egyptian population.

Patients and methods

Two hundred patients with AIS (within the first 24 h) were subjected to full neurological examination, assessment of stroke severity using National Institute of Health Stroke Scale (NIHSS) and measurement of serum IGF-1 levels. The control group included 100 subjects matched for age, gender, and conventional vascular risk factors.

Results

Serum IGF-1 levels were significantly reduced in cases of first AIS compared to control group. A reduced serum IGF-1 level was an independent risk factor for ischemic stroke with cut off value less than 148.3 ng/ml associated with increased AIS risk.

Conclusion

Lower IGF-1 levels are significantly related to risk of ischemic stroke occurrence, independent from other conventional risk factors in the Egyptian population.

A framework for selection of blood-based biomarkers for geroscience-guided clinical trials: report from the TAME Biomarkers Workgroup

Recent advances indicate that biological aging is a potentially modifiable driver of late-life function and chronic disease and have led to the development of geroscience-guided therapeutic trials such as TAME (Targeting Aging with MEtformin). TAME is a proposed randomized clinical trial using metformin to affect molecular aging pathways to slow the incidence of age-related multi-morbidity and functional decline. In trials focusing on clinical end-points (e.g., disease diagnosis or death), biomarkers help show that the intervention is affecting the underlying aging biology before sufficient clinical events have accumulated to test the study hypothesis. Since there is no standard set of biomarkers of aging for clinical trials, an expert panel was convened and comprehensive literature reviews conducted to identify 258 initial candidate biomarkers of aging and age-related disease. Next selection criteria were derived and applied to refine this set emphasizing: (1) measurement reliability and feasibility; (2) relevance to aging; (3) robust and consistent ability to predict all-cause mortality, clinical and functional outcomes; and (4) responsiveness to intervention. Application of these selection criteria to the current literature resulted in a short list of blood-based biomarkers proposed for TAME: IL-6, TNFα-receptor I or II, CRP, GDF15, insulin, IGF1, cystatin C, NT-proBNP, and hemoglobin A1c. The present report provides a conceptual framework for the selection of blood-based biomarkers for use in geroscience-guided clinical trials. This work also revealed the scarcity of well-vetted biomarkers for human studies that reflect underlying biologic aging hallmarks, and the need to leverage proposed trials for future biomarker discovery and validation.

Aging, inflammation and cancer

Aging is a key aspect of neoplasia at the level of cells, individuals and populations. Unrestrained expression and production of inflammatory mediators is a key feature of aging at the cellular and organism level. Inflammatory cells and mediators are a key component of the tumor microenvironment and drive tumor progression. Non-resolving smoldering inflammation increases the risk of cancer (the extrinsic pathway connecting inflammation and cancer). In the intrinsic pathway, genetic events that cause neoplasia (oncogenes and oncosupressor genes) orchestrate the construction of cancer-related inflammation. We argue that uncontrolled smoldering inflammation drives carcinogenesis in aging and acts as a common denominator linking aging and cancer.

Trajectories of IGF-I Predict Mortality in Older Adults: The Cardiovascular Health Study

Background

Disruption of insulin-like growth factor-I (IGF-I) increases health and life span in animal models, though this is unconfirmed in humans. If IGF-I stability indicates homeostasis, the absolute level of IGF-I may be less clinically relevant than maintaining an IGF-I setpoint.

Methods

Participants were 945 U.S. community-dwelling individuals aged ≥65 years enrolled in the Cardiovascular Health Study with IGF-I levels at 3-6 timepoints. We examined the association of baseline IGF-I level, trajectory slope, and variability around the trajectory with mortality.

Results

There were 633 deaths over median 11.3 years of follow-up. Lower IGF-I levels, declining or increasing slope, and increasing variability were each individually associated with higher mortality (all p < .001). In an adjusted model including all three trajectory parameters, baseline IGF-I levels <70 ng/mL (hazard ratio [HR] 1.58, 95% CI 1.28-1.96 relative to IGF-I levels of 170 ng/mL), steep declines and steep increases in trajectory slope (HR 2.22, 1.30-3.80 for a 15% decline; HR 1.40, 1.07-1.84 for a 10% decline; HR 1.80, 1.12-2.89 for a 15% increase; HR 1.31, 1.00-1.72 for a 10% increase, each vs no change), and variability ≥10% (HR 1.59, 1.09-2.32 for ≥ 30%; HR 1.36, 1.06-1.75 for 20%; and HR 1.17, 1.03-1.32 for 10% variability, each vs 0%) in IGF-I levels were independently associated with mortality.

Conclusions

In contrast to data from animal models, low IGF-I levels are associated with higher mortality in older humans. Irrespective of the actual IGF-I level, older individuals with stability of IGF-I levels have lower mortality than those whose IGF-I levels fluctuate over time.

Assessment of sarcopenia in virally suppressed HIV-infected Asians receiving treatment

OBJECTIVES

In a clinic-based, treated HIV-infected cohort, we identified individuals with sarcopenia and compared with age, sex and ethnically matched controls; and investigated associated risk factors and health outcomes.

DESIGN

Sarcopenia (age-related muscle loss) causes significant morbidity to the elderly, leading to frequent hospitalizations, disability and death. Few have characterized sarcopenia in the HIV-infected who experience accelerated aging.

METHODS

Sarcopenia was defined as low muscle mass with weak grip strength and/or slow gait speed using lower 20th percentiles of controls. Multivariate logistic and linear regression analyses were used to explore risk factors and health-related outcomes associated with sarcopenia among HIV-infected individuals.

RESULTS

We recruited 315 HIV-infected individuals aged at least 25 years with at least 1-year history of undetectable viral load on treatment (HIV RNA <50 copies/ml). Percentage of sarcopenia in 315 HIV-infected was 8%. Subsequently, 153 of the 315 were paired with age, sex and ethnically matched HIV-uninfected. The percentage of sarcopenia in the HIV-infected (n = 153) compared with uninfected (n = 153) were 10 vs. 6% (P = 0.193) respectively, whereas of those at least 50 years of age among them were 17% vs. 4% (P = 0.049), respectively. Associated risk factors among the HIV-infected include education level, employment status, BMI, baseline CD4 cell count, duration on NRTIs and GGT levels. Identified negative outcomes include mortality risk scores [5.42; 95% CI 1.46-9.37; P = 0.007) and functional disability (3.95; 95% CI 1.57-9.97; P = 0.004).

CONCLUSION

Sarcopenia is more prevalent in HIV-infected at least 50 years old compared with matched controls. Our findings highlight associations between sarcopenia with loss of independence and greater healthcare burden among treated HIV-infected individuals necessitating early recognition and intervention.

Frailty: the missing piece of the pre- hematopoietic cell transplantation assessment?

Hematopoietic stem cell transplantation (HSCT) represents a curative option for those afflicted with numerous hematologic malignancies and bone marrow failure syndromes. Advances and refinement of the HSCT process have resulted in increasing number of transplants performed on older patients in the recent years. Pre-transplant assessments (PTA) function to risk stratify patients prior to undergoing HSCT in an effort to predict those at higher risk of treatment-related toxicity, to inform risk/benefit assessments and to aid clinical decision making. Traditionally used risk stratification parameters such as chronologic age, comorbidity and performance status may not fully capture physical function, physiologic fitness, highlighting a need for improvement in PTA. Incorporation of frailty measurements in pre-HSCT assessments, particularly in elderly transplant candidates, may result in improving predictive ability of existing tools such as the Hematopoietic Cell Transplantation Comorbidity Index and Karnofsky performance status. Here, we review existing pre-HSCT assessment tools, measures of frailty that may aid in risk stratification for patients undergoing HSCT and directions for future research using frailty in the pre-HSCT setting.

Sarcopenia in elderly patients with type 2 diabetes mellitus: prevalence and related clinical factors

Aims

Sarcopenia, which shortens healthy life expectancy, has recently been attracting attention because the Japanese population is rapidly aging. In this preliminary study, we estimated the prevalence of elderly diabetic patients who were complicated with sarcopenia and searched for any related clinical factors.

Methods

Elderly (≥65 years of age) Japanese patients with type 2 diabetes mellitus were recruited by asking doctors to supply candidates for the study. The prevalence of sarcopenia was estimated based on the criteria proposed by the Asian Working Group for Sarcopenia in 2014.

Results

Two hundred eighty-eight patients (151 males) were accepted for the study. The prevalence of sarcopenia was 15.2% in males and 15.3% in females. Multiple logistic regression analysis indicated that sarcopenia was significantly correlated with serum high-sensitivity C-reactive protein in females, in addition to age and body mass index. Female patients were then classified into four groups according to the presence or absence of impaired muscle mass and/or impaired strength. Serum high-sensitivity C-reactive protein was significantly higher in the sarcopenia group (those with impaired muscle mass and impaired strength) than in the other three groups.

Conclusions

After clarifying the prevalence of sarcopenia in elderly Japanese patients with type 2 diabetes mellitus, we found that serum high-sensitivity C-reactive protein was significantly higher in female patients with sarcopenia than in female patients without sarcopenia. Elevated serum high-sensitivity C-reactive protein requires impaired muscle mass and impaired strength.

Genetic Variant in ACVR2B Is Associated with Lean Mass

INTRODUCTION

Low lean mass (LM) is a risk factor for chronic disease, a major cause of disability and diminished quality of life, and is a heritable trait. However, relatively few specific genetic factors have been identified as potentially influencing this trait.

METHODS

In this study, we selected 1493 single-nucleotide polymorphisms (SNP) in 155 candidate genes involved in anabolic, catabolic, growth hormone, and other related pathways and examined their association with LM, assessed by dual-energy x-ray absorptiometry, in a sample of 2760 non-Hispanic and Hispanic white postmenopausal women from the Women's Health Initiative (WHI) Observational Study. We assessed the replication of our top findings in a meta-analysis of 20 genome-wide association studies (n = 38,292) conducted by the Cohorts for Heart and Aging Research in Genomic Epidemiology Consortium Musculoskeletal Working Group.

RESULTS

We identified 32 SNPs that had nominally significant associations with LM in the WHI cohort. In the replication stage, we find that SNP rs2276541 in the activin A receptor, type IIB (ACVR2B), was significantly associated with LM (β = 0.15, P = 2.17 × 10). ACVR2B codes for a receptor for a negative regulator of skeletal muscle, myostatin, and has previously been identified in a candidate gene study as a determinant of skeletal muscle mass.

CONCLUSIONS

Our findings support a previously proposed role of ACVR2B allelic variation as a determinant of muscle mass and extend prior findings in men and women. Additional large-scale studies will be needed to confirm our findings in different populations.

Metabolites Associated With Circulating Interleukin-6 in Older Adults

Background

Circulating levels of the pro-inflammatory cytokine interleukin-6 (IL-6) levels are elevated in older adults, but mechanisms are unclear. In the current study, we used an untargeted metabolomic approach to develop an improved understanding about mechanisms related to circulating IL-6 in older adults.

Methods

Serum IL-6 values were log-transformed to normalize its distribution. Multivariable-adjusted linear regression was used to examine the association between 324 serum metabolites with log IL-6. Backward elimination linear regression was used to develop a metabolite predictor set representative of log IL-6.

Results

Thirty-six metabolites were significantly associated (p < 0.05 and q < 0.30) with log IL-6 in 73 older adults (average age, 78 years). Metabolites related to tryptophan metabolism (kynurenine, 3-indoxyl sulfate, indoleacetate, indolepropionate, C-glycosyltryptophan), infectious burden (C-glycosyltryptophan, N6-carbamoylthreonyladenosine, 1-methylurate, N-formylmethionine, N1-methyladenosine, 3-indoxyl sulfate, bilirubin (E,E), indoleacetate, γ-CEHC, N-acetylneuraminate), aryl hydrocarbon receptor activation and cytochrome P450 (CYP) 1A expression (kynurenine, 3-indoxyl sulfate, indoleacetate, N6-carbamoylthreonyladenosine, bilirubin, 1-methylurate) were positively associated, whereas metabolites related to CYP-mediated ω-oxidation (adipate, 8-hydroxyoctanoate, azelate, sebacate, undecanedioate, γ-CEHC), and peroxisome proliferator activated receptor-alpha (PPAR-α) activation (13 + 9-HODE, bilirubin, 5-oxoproline, cholesterol, glycerate, uridine) were negatively associated with log IL-6. The use of backward elimination regression identified tyrosine, cysteine, uridine, bilirubin, N-formylmethionine, indoleacetate, and 3-indoxyl sulfate to collectively explain 51% of the variance inherent in log IL-6.

Conclusions

These data suggest roles for tryptophan metabolism, infectious burden, activation of host defense, and detoxification through CYP1A-mediated pathways in mechanisms related to elevated inflammation, whereas CYP-mediated ω-oxidation and PPAR-α activation may be related to decreased inflammation in older adults.

Insulin-Like Growth Factor Is Associated with Changes in Body Composition with Antiretroviral Therapy Initiation

Growth hormone (GH)/insulin-like growth factor (IGF)-1 axis abnormalities have been associated with body composition changes among HIV-infected persons with wasting or lipodystrophy. Little is known of GH/IGF-1 axis alterations with antiretroviral therapy (ART) initiation or differing ART therapies. The AIDS Clinical Trials Group Prospective Evaluation of Antiretrovirals in Resource-Limited Settings (PEARLS) study was a prospective, randomized clinical trial of ART initiation with emtricitabine/tenofovir + efavirenz (FTC/TDF+EFV) versus lamivudine/zidovudine + efavirenz (3TC/ZDV+EFV) in HIV-1-infected individuals from resource-diverse settings. IGF-1 was measured from baseline, week 48, and week 96 stored serum samples. Multivariate models were constructed. 415 participants were included: 170 (41%) were randomized to FTC/TDF+EFV and 245 (59%) to 3TC/ZDV+EFV. The mean age was 35 years, 60% were black, 42% women. The mean IGF-1 level did not change significantly from baseline to week 96 (-0.65 ng/ml; 95% confidence interval (CI) -5.18-3.87), p = .78 and there were no differences by treatment arm at week 96, p = .74. Lower baseline IGF-1 was associated with age, non-white race, greater waist-hip ratio (WHR), low CD4 count, and lower baseline albumin (all p < .01) but not plasma HIV-1 RNA, body mass index, or treatment arm. Greater change in IGF-1 from baseline to 96 weeks was associated with female sex, smaller WHR change, lower baseline albumin, and higher baseline HIV-1 RNA (all p < .01). ART initiation with either ZDV or TDF did not significantly impact overall IGF-1 levels. Baseline and on-treatment changes in IGF-1 with ART initiation may be related to the body composition changes that occur after ART initiation.

Predictive value of multiple cytokines and chemokines for mortality in an admixed population: 15-year follow-up of the Bambui-Epigen (Brazil) cohort study of aging

Inflammation, particularly elevated IL-6 serum levels, has been associated with increased mortality risk, mostly in Caucasians. The influence of genetic ethno-racial background on this association is unknown. We examined associations between baseline serum levels of Interleukin-6 (IL-6) and other cytokines (IL1-2, TNF, IL-10, and IL1β) and chemokines (CCL2, CCL5, CXCL8, CXCL9 and CXCL10) with 15-year mortality in 1,191 admixed Brazilians aged 60years and over. Elevated IL6 level (but not other biomarkers) was associated with increased risk of deaths with fully adjusted hazard ratios of 1.51 (95% CI=1.15, 1.97), 1.54 (95% CI=1.20, 1.96) and 1.79 (95% CI=1.40, 2.29) for the 2nd, 3rd and the highest quartiles, respectively. Genomic African and Native American proportions did not modify the association (p>0.05). The discriminatory ability to predict death of a model based on IL-6 alone was similar as that of a comprehensive morbidity score (C statistics=0.59 and 0.60, respectively). The abilities of IL-6 and the morbidity score models to predict death remained stable for very long term after the baseline measurement. Our results indicate that genome-based African and Native American ancestries have no impact on the prognostic value of IL-6 for mortality.

Serum markers of inflammation and oxidative stress in sarcopenia

BACKGROUND

Sarcopenia is a geriatric syndrome characterized by the presence of low muscle mass and function. Possible mechanisms underlying sarcopenia include oxidative stress and elevation of inflammatory cytokines.

AIMS

The aim of the study was to evaluate the relationship between sarcopenia and biomarkers that may be involved in its pathogenesis and hence early detection.

METHODS

A total of 72 patients (36 sarcopenic and 36 non-sarcopenic) were included in the study. An experienced geriatric team applied comprehensive geriatric assessment to all patients. Anthropometric measures, gait speed and handgrip strength were recorded. Bioelectrical impedance analysis was used to assess skeletal muscle mass. In addition to routine clinical laboratory tests, serum adiponectin, thioredoxin-1 and pentraxin-3 levels were measured. Sarcopenia was defined according to the European Working Group on Sarcopenia in older Adults as the presence of low muscle mass and low muscle function or muscle performance.

RESULTS

Sarcopenic patients were more likely to be functionally dependent and had lower scores on comprehensive geriatric assessment tools. Erythrocyte sedimentation rate (ESR) and C-reactive protein levels were significantly higher in the sarcopenic group. There was no significant difference in serum levels of thioredoxin-1 and pentraxin-3. Sarcopenic patients had lower levels of hemoglobin, albumin, total protein, calcium, triglycerides, uric acid and adiponectin (p < 0.05). Hypertension and body mass index were inversely correlated with sarcopenia whereas ESR was positively correlated.

DISCUSSION AND CONCLUSION

The present study demonstrated an association of sarcopenia with inflammatory markers CRP, ESR and adiponectin. Long-term prospective studies are warranted to confirm the relationship between markers oxidative stress and age related muscle decline.

(Dis)Trust your gut: the gut microbiome in age-related inflammation, health, and disease

Chronic inflammation represents one of the most consistent biologic features of aging. However, the precise etiology of persistent low-grade increases in inflammation remains unclear. Recent evidence suggests that the gut microbiome may play a key role in age-related inflammation. Indeed, several studies have indicated that older adults display an altered composition of the gut microbiota, and early evidence indicates that this dysbiosis is associated with the presence of several key circulating inflammatory analytes. The present review summarizes knowledge on age-related inflammation and discusses how potential relationships with gut dysbiosis may lead to novel treatment strategies in the future."The pattern of disease is an expression of the response of man to his total environment (physical, biological, and social); this response is, therefore, determined by anything that affects man himself or his environment." - Rene Dubos, 1961.

Factors Affecting Sarcopenia in Korean Adults by Age Groups

Objectives

This study aimed to investigate factors affecting sarcopenia in different age groups among Korean adults aged 20 years or older.

Methods

In this secondary analysis, data were collected from records for 17,968, participants who participated in the Korea National Health and Nutrition Examination Survey during 2008–2011. Data were analyzed using multiple logistic regression to determine the associated factors of sarcopenia by age groups.

Results

The prevalence of sarcopenia increased significantly with age. Physical activity, blood pressure, waist circumference, triglycerides, vitamin D level were found to be factors significantly associated with sarcopenia in all age groups. Total energy intake was found to be a factor that is significantly associated with sarcopenia among the adults aged 20–39 years. Fasting glucose, suicidal ideation, perceived health status, mobility problem, pain/discomfort, total energy intake were found to be factors associated with sarcopenia in the adults aged 40–64 years. Sex, residential area, smoking, drinking, fasting glucose, osteoarthritis, fall experience, usual activity problem, protein intake were factors associated with sarcopenia in the adults over 65 years of age.

Conclusion

The findings show that sarcopenia in adults and the associated factors were different by age groups. Thus, these factors should be considered in the development of intervention programs for the care and prevention of sarcopenia, and such programs should be modified according to different age groups.

Factors Associated with Decreased Lean Tissue Index in Patients with Chronic Kidney Disease

Muscle wasting is common and is associated with increased morbidity and mortality in patients with chronic kidney disease (CKD). However, factors associated with decreased muscle mass in CKD patients are seldom reported. We performed a cross-sectional study of 326 patients (age 65.8 ± 13.3 years) with stage 3–5 CKD who were not yet on dialysis. Muscle mass was determined using the Body Composition Monitor (BCM), a multifrequency bioimpedance spectroscopy device, and was expressed as the lean tissue index (LTI, lean tissue mass/height²). An LTI of less than 10% of the normal value (low LTI) indicates muscle wasting. Patients with low LTI (n = 40) tended to be diabetic, had significantly higher fat tissue index, urine protein creatinine ratio, and interleukin-6 and tumor necrosis factor-α levels, but had significantly lower serum albumin and hemoglobin levels compared with those with normal LTI. In multivariate linear regression analysis, age, sex, cardiovascular disease, and interleukin-6 were independently associated with LTI. Additionally, diabetes mellitus remained an independent predictor of muscle wasting according to low LTI by multivariate logistic regression analysis. We conclude that LTI has important clinical correlations. Determination of LTI may aid in clinical assessment by helping to identify muscle wasting among patients with stage 3–5 CKD.

Subtypes of physical frailty: Latent class analysis and associations with clinical characteristics and outcomes

Frailty is a well-recognized geriatric syndrome with various definitions and conceptual frameworks. This study aimed to use latent class analysis to discover potential subtypes of pre-frail and frail older people. Data from the I-Lan Longitudinal Aging Study (ILAS), a community-based cohort study was used for analysis. Latent class analysis was applied to characterize classes or subgroups with different frailty phenotypes among ILAS participants targeting older adults aged 65 and above, capable of completing a 6-meter walk, without severe major or life threatening diseases, and not institutionalized. Latent class analysis identified three distinct subgroups with different frailty phenotypes: non-mobility-type (weight loss and exhaustion), mobility-type frailty (slowness and weakness), and low physical activity. Comparing these groups with the robust group, people with mobility-type frailty had poorer body composition, worse bone health, poorer cognitive function, lower survival (hazard ratio: 6.82, p = 0.019), and poorer overall health outcomes (hazard ratio: 1.67, p = 0.040). People in the non-mobility-type group had poorer bone health and more metabolic serum abnormalities. In conclusion, mobility-type frailty was a better predictor of adverse outcomes. However, further investigation is needed to evaluate how these phenotypic subgroups may help in predicting prognosis or in developing interventions.

CD34+ cell count predicts long lasting life in the oldest old

Circulating progenitor cells (CPCs) represent a pool of cells capable of differentiating into mature cells of different organs and systems, promoting tissue maintenance and repair. Among CPCs, CD34+cells (CD34+CPCs) seem to predict outcome in CV disease, also in elderly people. A decline in CD34+CPCs was reported with advancing age. Moreover, aging is associated with a state of chronic inflammation, influencing life expectancy. Our purpose was to investigate a 10-year predictive ability of CD34+CPCs, inflammatory marker levels, classic CV risk factors (CVRFs), and Framingham Risk Score (FRS) in a population of healthy, self-sufficient octogenarians. We found that baseline CD34+CPCs was strongly associated with mortality, showing a significant difference in CD34+CPC numbers between deceased and living patients. Moreover, by dividing our patients into tertiles based on age reached, this difference was more remarkable the higher the age reached. Regressive analyses suggested that the chances of reaching an older age depend on higher CD34+CPCs at baseline and are not significantly affected by inflammatory markers levels, FRS, CVFRs, or HDL-C levels. We found that higher CD34+CPCs predict longer life also in the oldest old, providing additional insights on the predictive role of CD34+CPCs in subjects aged 80 years or more.

Systemic Inflammation in the Genesis of Frailty and Sarcopenia: An Overview of the Preventative and Therapeutic Role of Exercise and the Potential for Drug Treatments

The clinical, pathological and biological characteristics of frailty and sarcopenia are becoming better understood and defined, including the role of systemic inflammation. It is increasingly apparent that in older adults there is a tendency for the innate immune network to shift toward a pro-inflammatory setting, often due to the presence of chronic inflammatory diseases but also associated with age alone in some individuals. Furthermore, acute inflammation tends to resolve more slowly and less completely in many elderly people. Inflammation contributes to the pathogenesis of sarcopenia and other components of the frailty syndrome. Blood levels of inflammatory cytokines and acute phase proteins, are reduced by exercise, and there is a growing body of epidemiological, observational and intervention research that indicates that regular moderate exercise improves strength, function, morbidity and mortality in middle-aged and elderly adults. There is also an increasing awareness of the potential role of drugs to ameliorate inflammation in the context of frail old age, which might be particularly useful for people who are unable to take part in exercise programs, or as adjunctive treatment for those who can. Drugs that shift the innate immune biochemical network toward an anti-inflammatory setting, such as methyl-xanthines and 4-amino quinolones, could be of value. For example, theophylline has been shown to induce a 20 percent fall in pro-inflammatory tumor necrosis factor (TNF) and 180 percent rise in anti-inflammatory interleukin-10 production by peripheral blood monocytes, and a fall of 45 percent in interferon-gamma (IF-gamma) release. Such properties could be of therapeutic benefit, particularly to re-establish a less inflamed baseline after acute episodes such as sepsis and trauma.

Type 2 diabetes mellitus is associated with increased risks of sarcopenia and pre-sarcopenia in Chinese elderly

Sarcopenia is a condition characterized by progressive and generalized loss of skeletal muscle mass and function. In this study, we used a cross-sectional study with 1090 community-dwelling Chinese citizens aged 60 years and older to evaluate the association of type 2 diabetes mellitus (T2DM) with the risk of sarcopenia and pre-sarcopenia. Sarcopenia was defined using the Asian Working Group for Sarcopenia (AWGS) criteria that include both muscle mass and muscle function/physical activity. Pre-sarcopenia was defined as having low skeletal muscle index but with normal muscle/physical activity. The prevalence of sarcopenia and pre-sarcopenia was significantly higher in T2DM patients than in healthy controls (14.8% vs. 11.2%, p = 0.035 for sarcopenia, and 14.4% vs. 8.4%, p = 0.002 for pre-sarcopenia). In multivariate logistic regression analyses adjusting by age, gender, anti-diabetic medication, energy intake, protein intake, physical activity, and visceral fat area, we found that Chinese elderly with T2DM exhibited significantly increased risks of sarcopenia (OR = 1.37, 95% CI = 1.02-2.03) and pre-sarcopenia (OR = 1.73, 95% CI = 1.10-2.83) compared to non-diabetic individuals. This is the first study to evaluate the association of T2DM with the risks of sarcopenia and pre-sarcopenia in China. Among a group of community-dwelling Chinese elderly, T2DM was significantly associated with increased risks of sarcopenia and pre-sarcopenia.

Emerging roles for histone deacetylases in age-related muscle atrophy

BACKGROUND: Skeletal muscle atrophy during aging, a process known as sarcopenia, is associated with muscle weakness, frailty, and the loss of independence in older adults. The mechanisms contributing to sarcopenia are not totally understood, but muscle fiber loss due to apoptosis, reduced stimulation of anabolic pathways, activation of catabolic pathways, denervation, and altered metabolism have been observed in muscle from old rodents and humans.

OBJECTIVE: Recently, histone deacetylases (HDACs) have been implicated in muscle atrophy and dysfunction due to denervation, muscular dystrophy, and disuse, and HDACs play key roles in regulating metabolism in skeletal muscle. In this review, we will discuss the role of HDACs in muscle atrophy and the potential of HDAC inhibitors for the treatment of sarcopenia.

CONCLUSIONS: Several HDAC isoforms are potential targets for intervention in sarcopenia. Inhibition of HDAC1 prevents muscle atrophy due to nutrient deprivation. HDAC3 regulates metabolism in skeletal muscle and may inhibit oxidative metabolism during aging. HDAC4 and HDAC5 have been implicated in muscle atrophy due to denervation, a process implicated in sarcopenia. HDAC inhibitors are already in use in the clinic, and there is promise in targeting HDACs for the treatment of sarcopenia.

Ageing and inflammation in patients with HIV infection

Nowadays, HIV⁺ patients have an expected lifespan that is only slightly shorter than healthy individuals. For this reason, along with the fact that infection can be acquired at a relatively advanced age, the effects of ageing on HIV⁺ people have begun to be evident. Successful anti-viral treatment is, on one hand, responsible for the development of side effects related to drug toxicity; on the other hand, it is not able to inhibit the onset of several complications caused by persistent immune activation and chronic inflammation. Therefore, patients with a relatively advanced age, i.e. aged more than 50 years, can experience pathologies that affect much older citizens. HIV⁺ individuals with non-AIDS-related complications can thus come to the attention of clinicians because of the presence of neurocognitive disorders, cardiovascular diseases, metabolic syndrome, bone abnormalities and non-HIV-associated cancers. Chronic inflammation and immune activation, observed typically in elderly people and defined as 'inflammaging', can be present in HIV⁺ patients who experience a type of premature ageing, which affects the quality of life significantly. This relatively new condition is extremely complex, and important factors have been identified as well as the traditional behavioural risk factors, e.g. the toxicity of anti-retroviral treatments and the above-mentioned chronic inflammation leading to a functional decline and a vulnerability to injury or pathologies. Here, we discuss the role of inflammation and immune activation on the most important non-AIDS-related complications of chronic HIV infection, and the contribution of aging per se to this scenario.

Attenuated IGF-1 predicts all-cause and cardiovascular mortality in a Black population: A five-year prospective study

BACKGROUND

Inconsistent findings are reported on whether insulin-like growth factor-1 (IGF-1) is protective or harmful in predicting hypertension, carotid wall thickness and mortality. We determined the five-year prognostic value of IGF-1 for these outcomes in a large Black population prone to hypertension and cardiovascular disease.

DESIGN

A longitudinal study as part of the PURE (Prospective Urban and Rural Epidemiology) study, North West Province, South Africa.

METHODS

We measured IGF-1 and IGF binding protein-3 (IGFBP-3) in 1038 HIV-uninfected participants (age range 32-94 years) and assessed blood pressure, carotid intima-media thickness and mortality.

RESULTS

Over five years 116 deaths occurred. Baseline IGF-1 was similar in survivors and non-survivors (p = 0.50), but tended to be higher in survivors upon adjustment for IGFBP-3 and covariates (p = 0.061). Normotensives and hypertensives (p = 0.072), and those with carotid intima-media thickness < 0.9 mm and ≥ 0.9 mm also displayed similar baseline IGF-1 (p = 0.55). Multivariable-adjusted Cox-regression indicated high IGF-1 predicting lower risk for all-cause mortality (hazard ratio 0.45; 0.23-0.88) and cardiovascular mortality (hazard ratio 0.26; 0.08-0.83) when also adjusting for IGFBP-3. When including normo- and hypertensives at baseline, high IGF-1 was related to normotension at follow-up (hazard ratio 0.68; 0.49-0.95). We found no association with carotid intima-media thickness (hazard ratio 0.59; 0.31-1.14).

CONCLUSION

In a Black South African population with low socio-economic status and harmful health behaviours, we found a protective independent association between IGF-1 and hypertension, cardiovascular and all-cause mortality, with no association with carotid wall thickness.

The Somatotropic Axis in Human Aging: Framework for the Current State of Knowledge and Future Research

Mutations resulting in reduced signaling of the growth hormone/insulin-like growth factor-1 (GH/IGF-1) axis are associated with increased life- and healthspan across model organisms. Similar findings have been noted in human cohorts with functional mutations in the somatotropic axis, suggesting that this pathway may also be relevant to human aging and protection from age-related diseases. While epidemiological data indicate that low circulating IGF-1 level may protect aging populations from cancer, results remain inconclusive regarding most other diseases. We propose that studies in humans and animals need to consider differences in sex, pathway function, organs, and time-specific effects of GH/IGF-1 signaling in order to better define the role of the somatotropic axis in aging. Agents that modulate signaling of the GH/IGF-1 pathway are available for human use, but before they can be implemented in clinical studies that target aging and age-related diseases, researchers need to address the challenges discussed in this Review.

Genetic variation and exercise-induced muscle damage: implications for athletic performance, injury and ageing

Prolonged unaccustomed exercise involving muscle lengthening (eccentric) actions can result in ultrastructural muscle disruption, impaired excitation-contraction coupling, inflammation and muscle protein degradation. This process is associated with delayed onset muscle soreness and is referred to as exercise-induced muscle damage. Although a certain amount of muscle damage may be necessary for adaptation to occur, excessive damage or inadequate recovery from exercise-induced muscle damage can increase injury risk, particularly in older individuals, who experience more damage and require longer to recover from muscle damaging exercise than younger adults. Furthermore, it is apparent that inter-individual variation exists in the response to exercise-induced muscle damage, and there is evidence that genetic variability may play a key role. Although this area of research is in its infancy, certain gene variations, or polymorphisms have been associated with exercise-induced muscle damage (i.e. individuals with certain genotypes experience greater muscle damage, and require longer recovery, following strenuous exercise). These polymorphisms include ACTN3 (R577X, rs1815739), TNF (-308 G>A, rs1800629), IL6 (-174 G>C, rs1800795), and IGF2 (ApaI, 17200 G>A, rs680). Knowing how someone is likely to respond to a particular type of exercise could help coaches/practitioners individualise the exercise training of their athletes/patients, thus maximising recovery and adaptation, while reducing overload-associated injury risk. The purpose of this review is to provide a critical analysis of the literature concerning gene polymorphisms associated with exercise-induced muscle damage, both in young and older individuals, and to highlight the potential mechanisms underpinning these associations, thus providing a better understanding of exercise-induced muscle damage.

Trajectories of function and biomarkers with age: the CHS All Stars Study

BACKGROUND

Multimorbidity is a major driver of physical and cognitive impairment, but rates of decline are also related to ageing. We sought to determine trajectories of decline in a large cohort by disease status, and examined their correspondence with biomarkers of ageing processes including growth hormone, sex steroid, inflammation, visceral adiposity and kidney function pathways.

METHODS

We have followed the 5888 participants in the Cardiovascular Health Study (CHS) for healthy ageing and longevity since 1989-90. Gait speed, grip strength, modified mini-mental status examination (3MSE) and the digit symbol substitution test (DSST) were assessed annually to 1998-99 and again in 2005-06. Insulin-like growth hormone (IGF-1), dehydroepiandrosterone sulphate (DHEAS), interleukin-6 (IL-6), adiponectin and cystatin-C were assessed 3-5 times from stored samples. Health status was updated annually and dichotomized as healthy vs not healthy. Trajectories for each function measure and biomarker were estimated using generalized estimating equations as a function of age and health status using standardized values.

RESULTS

Trajectories of functional decline showed strong age acceleration late in life in healthy older men and women as well as in chronically ill older adults. Adiponectin, IL-6 and cystatin-C tracked with functional decline in all domains; cystatin-C was consistently associated with functional declines independent of other biomarkers. DHEAS was independently associated with grip strength and IL-6 with grip strength and gait speed trajectories.

CONCLUSIONS

Functional decline in late life appears to mark a fundamental ageing process in that it occurred and was accelerated in late life regardless of health status. Cystatin C was most consistently associated with these functional declines.

Sarcopenia and mortality among a population-based sample of community-dwelling older adults

BACKGROUND

Sarcopenia is a risk-factor for all-cause mortality among older adults, but it is unknown if sarcopenia predisposes older adults to specific causes of death. Further, it is unknown if the prognostic role of sarcopenia differs between males and females, and obese and non-obese individuals.

METHODS

A population-based cohort study among 4425 older adults from the Third National Health and Nutrition Survey (1988-1994). Muscle mass was quantified using bioimpedance analysis, and muscle function was quantified using gait speed. Multivariable-adjusted Cox regression analysis examined the relationship between sarcopenia and mortality outcomes.

RESULTS

The mean age of study participants was 70.1 years. The prevalence of sarcopenia was 36.5%. Sarcopenia associated with an increased risk of all-cause mortality [hazard ratio (HR): 1.29 (95% confidence interval (95% CI): 1.13-1.47); P < 0.001] among males and females. Sarcopenia associated with an increased risk of cardiovascular-specific mortality among females [HR: 1.61 (95% CI: 1.22-2.12); P = 0.001], but not among males [HR: 1.07 (95% CI: 0.81-1.40; P = .643); P interaction = 0.079]. Sarcopenia was not associated with cancer-specific mortality among males and females [HR: 1.07 (95% CI: 0.78-1.89); P = 0.672]. Sarcopenia associated with an increased risk of mortality from other causes (i.e. non-cardiovascular and non-cancer) among males and females [HR: 1.32 (95% CI: 1.07-1.62); P = 0.008]. Obesity, defined using body mass index (P interaction = 0.817) or waist circumference (P interaction = 0.219) did not modify the relationship between sarcopenia and all-cause mortality.

CONCLUSIONS

Sarcopenia is a prevalent syndrome that is associated with premature mortality among community-dwelling older adults. The prognostic value of sarcopenia may vary by cause-specific mortality and differ between males and females.

Handgrip strength is inversely and independently associated with multimorbidity among older women: Results from the KORA-Age study

BACKGROUND

Data on the association between handgrip strength and multimorbidity (MMB) are missing.

AIM

The purpose of this study was to examine if handgrip strength is related to MMB in a large population-based sample of older persons.

METHODS

The cross-sectional analysis was based on 1079 older people (aged 65-94years), who participated in the KORA-Age study in the Augsburg region, southern Germany. Participants underwent an interview and extensive examinations, including anthropometric measurements, registration of chronic diseases, determination of health-related behaviors (smoking, alcohol intake and physical activity), collection of blood samples, and muscle strength measurement using hand-grip dynamometry.

RESULTS

In men, handgrip strength correlated strongly with the number of co-existing diseases (r=-0.176, p<0.001), and the same pattern was observed for women (r=-0.287, p<0.001). Among women, handgrip strength in the lower tertile compared to the upper tertile was significantly associated with an increased odds of having MMB (OR: 2.57, 95% CI: 1.30-5.07, p=0.007) after controlling for age, BMI, education, alcohol intake, smoking habits, medications number, inflammatory markers, telomere length and levels of physical activity. Contrary, no significant association between handgrip strength and MMB was found among men (OR: 1.32, 95% CI: 0.73-2.40, p=0.362) after multivariable adjustment.

CONCLUSION

Lower levels of handgrip strength are associated with a higher odd of MMB among older women even after adjusting for traditional and novel confounders. Increasing the levels of muscular strength in older women seems to be important in order to reduce the risk for the co-occurrence of multiple chronic diseases.

Insulin-Like Growth Factor-1 Receptor Deficiency in Macrophages Accelerates Atherosclerosis and Induces an Unstable Plaque Phenotype in Apolipoprotein E-Deficient Mice

BACKGROUND

We have previously shown that systemic infusion of insulin-like growth factor-1 (IGF-1) exerts anti-inflammatory and antioxidant effects and reduces atherosclerotic burden in apolipoprotein E (Apoe)-deficient mice. Monocytes/macrophages express high levels of IGF-1 receptor (IGF1R) and play a pivotal role in atherogenesis, but the potential effects of IGF-1 on their function are unknown.

METHODS AND RESULTS

To determine mechanisms whereby IGF-1 reduces atherosclerosis and to explore the potential involvement of monocytes/macrophages, we created monocyte/macrophage-specific IGF1R knockout (MΦ-IGF1R-KO) mice on an Apoe(-/-) background. We assessed atherosclerotic burden, plaque features of stability, and monocyte recruitment to atherosclerotic lesions. Phenotypic changes of IGF1R-deficient macrophages were investigated in culture. MΦ-IGF1R-KO significantly increased atherosclerotic lesion formation, as assessed by Oil Red O staining of en face aortas and aortic root cross-sections, and changed plaque composition to a less stable phenotype, characterized by increased macrophage and decreased α-smooth muscle actin-positive cell population, fibrous cap thinning, and decreased collagen content. Brachiocephalic artery lesions of MΦ-IGF1R-KO mice had histological features implying plaque vulnerability. Macrophages isolated from MΦ-IGF1R-KO mice showed enhanced proinflammatory responses on stimulation by interferon-γ and oxidized low-density lipoprotein and elevated antioxidant gene expression levels. Moreover, IGF1R-deficient macrophages had decreased expression of ABCA1 and ABCG1 and reduced lipid efflux.

CONCLUSIONS

Our data indicate that macrophage IGF1R signaling suppresses macrophage and foam cell accumulation in lesions and reduces plaque vulnerability, providing a novel mechanism whereby IGF-1 exerts antiatherogenic effects.

Systemic inflammation after critical illness: relationship with physical recovery and exploration of potential mechanisms

BACKGROUND

Physical recovery following critical illness is slow, often incomplete and is resistant to rehabilitation interventions. We aimed to explore the contribution of persisting inflammation to recovery, and investigated the potential role of human cytomegalovirus (HCMV) infection in its pathogenesis.

METHODS

In an a priori nested inflammatory biomarker study in a post-intensive care unit (ICU) rehabilitation trial (RECOVER; ISRCTN09412438), surviving adult ICU patients ventilated >48 h were enrolled at ICU discharge and blood sampled at ICU discharge (n=184) and 3 month follow-up (N=123). C-reactive protein (CRP), human neutrophil elastase (HNE), interleukin (IL)-1β, IL-6, IL-8, transforming growth factor β1 (TGFβ1) and secretory leucocyte protease inhibitor (SLPI) were measured. HCMV IgG status was determined (previous exposure), and DNA PCR measured among seropositive patients (lytic infection). Physical outcome measures including the Rivermead Mobility Index (RMI) were measured at 3 months.

RESULTS

Many patients had persisting inflammation at 3 months (CRP >3 mg/L in 59%; >10 mg/L in 28%), with proinflammatory phenotype (elevated HNE, IL-6, IL-8, SLPI; low TGFβ1). Poorer mobility (RMI) was associated with higher CRP (β=0.13; p<0.01) and HNE (β=0.32; p=0.03), even after adjustment for severity of acute illness and pre-existing co-morbidity (CRP β=0.14; p<0.01; HNE β=0.30; p=0.04). Patients seropositive for HCMV at ICU discharge (63%) had a more proinflammatory phenotype at 3 months than seronegative patients, despite undetectable HMCV by PCR testing.

CONCLUSIONS

Inflammation is prevalent after critical illness and is associated with poor physical recovery during the first 3 months post-ICU discharge. Previous HCMV exposure is associated with a proinflammatory phenotype despite the absence of detectable systemic viraemia.

TRIAL REGISTRATION NUMBER

ISRCTN09412438, post results.

Insulin-like growth factor 1 prevents diastolic and systolic dysfunction associated with cardiomyopathy and preserves adrenergic sensitivity

AIMS

Insulin-like growth factor 1 (IGF-1)-dependent signalling promotes exercise-induced physiological cardiac hypertrophy. However, the in vivo therapeutic potential of IGF-1 for heart disease is not well established. Here, we test the potential therapeutic benefits of IGF-1 on cardiac function using an in vivo model of chronic catecholamine-induced cardiomyopathy.

METHODS

Rats were perfused with isoproterenol via osmotic pump (1 mg kg(-1) per day) and treated with 2 mg kg(-1) IGF-1 (2 mg kg(-1) per day, 6 days a week) for 2 or 4 weeks. Echocardiography, ECG, and blood pressure were assessed. In vivo pressure-volume loop studies were conducted at 4 weeks. Heart sections were analysed for fibrosis and apoptosis, and relevant biochemical signalling cascades were assessed.

RESULTS

After 4 weeks, diastolic function (EDPVR, EDP, tau, E/A ratio), systolic function (PRSW, ESPVR, dP/dtmax) and structural remodelling (LV chamber diameter, wall thickness) were all adversely affected in isoproterenol-treated rats. All these detrimental effects were attenuated in rats treated with Iso+IGF-1. Isoproterenol-dependent effects on BP were attenuated by IGF-1 treatment. Adrenergic sensitivity was blunted in isoproterenol-treated rats but was preserved by IGF-1 treatment. Immunoblots indicate that cardioprotective p110α signalling and activated Akt are selectively upregulated in Iso+IGF-1-treated hearts. Expression of iNOS was significantly increased in both the Iso and Iso+IGF-1 groups; however, tetrahydrobiopterin (BH4) levels were decreased in the Iso group and maintained by IGF-1 treatment.

CONCLUSION

IGF-1 treatment attenuates diastolic and systolic dysfunction associated with chronic catecholamine-induced cardiomyopathy while preserving adrenergic sensitivity and promoting BH4 production. These data support the potential use of IGF-1 therapy for clinical applications for cardiomyopathies.

Hypertension and aging

Hypertension is a highly prevalent condition with numerous health risks, and the incidence of hypertension is greatest among older adults. Traditional discussions of hypertension have largely focused on the risks for cardiovascular disease and associated events. However, there are a number of collateral effects, including risks for dementia, physical disability, and falls/fractures which are increasingly garnering attention in the hypertension literature. Several key mechanisms--including inflammation, oxidative stress, and endothelial dysfunction--are common to biologic aging and hypertension development and appear to have key mechanistic roles in the development of the cardiovascular and collateral risks of late-life hypertension. The objective of the present review is to highlight the multi-dimensional risks of hypertension among older adults and discuss potential strategies for treatment and future areas of research for improving overall care for older adults with hypertension.

IGFBP-1 predicts all-cause mortality in elderly women independently of IGF-I

OBJECTIVE

Previous studies on the insulin-like growth factor (IGF) system and mortality have shown ambiguous results. We investigated the association between IGF-I and insulin- like growth factor binding protein-1 (IGFBP-1) with all-cause mortality in an elderly female Swedish population.

DESIGN AND METHODS

A prospective cohort study of elderly women (n=338) aged between 68 and 79 years (mean age 72 years) with a mean follow-up time of 9.9 years. Baseline data in the PRIMOS (Primary Health Care and Osteoporosis) study were collected between 1999 and 2001. Data of risk factors for cardiovascular disease were collected. Death rates were registered from the Swedish Cause of Death register for the period 1999-2009. Cox regression models were used to calculate hazard ratios. IGF-I and IGFBP-1 levels were separately divided into 3 groups (high, medium and low), with cut offs at the 30th and the 70th percentiles.

RESULTS

In a fully adjusted Cox proportional hazard model, increased risk of mortality was shown for women with high serum levels of IGFBP-1, HR 3.03 (95% CI 1.64-5.63) and also with low serum levels of IGFBP-1, HR 1.98 (95% CI 1.03-3.81), compared to women with moderate levels. No significant association between IGF-I and mortality was observed.

CONCLUSIONS

High and low serum insulin-like IGFBP-1 levels were associated with an increased risk of all-cause mortality in elderly women, compared to moderate levels.

Effect of ZIP2 Gln/Arg/Leu (rs2234632) polymorphism on zinc homeostasis and inflammatory response following zinc supplementation

Zinc dyshomeostasis may lead to an augmented production of proinflammatory cytokines promoting chronic inflammation and increasing the susceptibility to age-related diseases. Several studies suggest that the zinc transporter protein ZIP2 may play a relevant role in the immune system especially during zinc deficiency, while a polymorphism on the coding region of ZIP2 gene (Gln/Arg/Leu) has been associated with severe carotid artery disease. The aim of this study is to investigate the role of ZIP2 SNP on zinc and inflammatory status in 1090 elderly healthy free-living subjects enrolled in the ZincAge project and to assess the effect of zinc supplementation on zinc status, inflammatory mediators, and zinc transporter expression depending on ZIP2 genotype. ZIP2 Leu- (Arg43Arg) carriers showed enhanced IL-6, TNF-α, and RANTES plasma levels associated with decreased free cytosolic zinc in PBMCs and an upregulation of zinc transporters ZIP2, ZIP8, and Znt1. Moreover, Leu- subjects displayed significant decrement of inflammatory mediators such as MCP-1, TNF-α, and RANTES following zinc supplementation. In summary, this investigation provides new evidence on the effect of ZIP2 Gln/Arg/Leu polymorphism on proinflammatory mediators and zinc homeostasis in elderly population with a more pronounced anti-inflammatory effect of zinc supplementation in subjects carrying ZIP2 Leu- (Arg43Arg) genotype. These novel findings could be useful in identifying elderly subjects who may benefit of zinc intervention to decrease the inflammatory status and to prevent or delay the development of age-related diseases.

Risk of Mortality According to Body Mass Index and Body Composition Among Postmenopausal Women

Obesity, often defined as a body mass index (BMI; weight (kg)/height (m)(2)) of 30 or higher, has been associated with mortality, but age-related body composition changes can be masked by stable BMI. A subset of Women's Health Initiative participants (postmenopausal women aged 50-79 years) enrolled between 1993 and 1998 who had received dual-energy x-ray absorptiometry scans for estimation of total body fat (TBF) and lean body mass (LBM) (n = 10,525) were followed for 13.6 (standard deviation, 4.6) years to test associations between BMI, body composition, and incident mortality. Overall, BMI ≥35 was associated with increased mortality (adjusted hazard ratio (HR) = 1.45, 95% confidence interval (CI): 1.16, 1.82), while TBF and LBM were not. However, an interaction between age and body composition (P < 0.001) necessitated age stratification. Among women aged 50-59 years, higher %TBF increased risk of death (HR = 2.44, 95% CI: 1.38, 4.34) and higher %LBM decreased risk of death (HR = 0.41, 95% CI: 0.23, 0.74), despite broad-ranging BMIs (16.4-69.1). However, the relationships were reversed among women aged 70-79 years (P < 0.05). BMI did not adequately capture mortality risk in this sample of postmenopausal women. Our data suggest the clinical utility of evaluating body composition by age group to more robustly assess mortality risk among postmenopausal women.