Effect of inflammation on handgrip strength in the non-critically ill is independent from age, gender and body composition

The combined effect of handgrip strength and obesity phenotype on the risk of stroke in Chinese middle-aged and elderly: A cohort study

OBJECTIVE

The aim of this study was to investigate the combined effect of handgrip strength (HGS) and obesity phenotype on the risk of stroke in Chinese middle-aged and elderly people.

METHODS

The data was used from the China Health and Retirement Longitudinal Study (CHARLS). Middle-aged and older adults who participated in surveys between 2011 and 2018 were included in the study. They were divided into 4 different types of obesity phenotypes based on obesity and metabolic status: metabolically healthy non-overweight/obesity (MHNO), metabolically healthy overweight/obesity (MHO), metabolically abnormal non-overweight/obesity (MANO), and metabolically abnormal overweight/obesity (MAO). The HGS level was divided into low and high groups according to the median values. Cox proportional risk regression model was used to analyze the joint effect of HGS and obesity phenotype on the risk of stroke among participants.

RESULTS

A total of 7904 participants aged 58.89±9.08 years were included in this study. After adjusting for potential confounders, high HGS&MHO (HR=1.86, 95 % CI=1.12-3.09), high HGS&MANO (HR=2.01, 95 %CI=1.42-2.86), high HGS&MAO (HR=2.01, 95 % CI=1.37-2.93), low HGS&MHNO (HR=1.57, 95 % CI=1.00-2.46), low HGS&MHO (HR=2.09, 95 % CI=1.29-3.38), low HGS&MANO (HR=2.02, 95 % CI=1.35-3.03), and low HGS&MAO (HR=2.48, 95 % CI=1.72-3.58) group had significantly higher risks of stroke than the high HGS&MHNO group.

CONCLUSION

The coexistence of metabolically unhealthy and low HGS can synergistically increase the risk of stroke in Chinese middle-aged and elderly people.

The relationship between muscle strength and epicardial fat in healthy adults

BACKGROUND

Muscular strength and muscle mass are considered key factors for healthy ageing. Modification of body composition and redistribution of adipose tissue has been described in advanced age. Muscle strength has an important predictive role for health outcomes. However, little is known regarding the relationship between muscle strength and epicardial fat.

METHODS AND MATERIALS

In a cohort of healthy adults following physical capacity evaluations, anthropometric measurements, handgrip strength (HGS), echocardiography and bioimpedance analysis (BIA) were performed. Kruskal-Wallis test, Spearman's correlation and regression analysis adjusted for confounders were applied.

RESULTS

A total population of 226 adults, age range 18-83 years, were included. Epicardial fat thickness resulted significantly associated with age p < 0.001, HGS (p < 0.001). Regression analysis adjusted for confounders revealed an independent relationship between handgrip strength and epicardial fat thickness: regression coefficient: -1.34; R2 = 0.27 and p = 0.044.

CONCLUSIONS

The relationship between epicardial fat and muscle strength is inverse and independent. Implementation of HGS measurement may be useful for the identification of subjects with excessive epicardial fat and cardiovascular risk. Measurement of epicardial fat could be helpful in the early detection of physical decline associated to ageing.

Chronic Astrocytic TNFα Production in the Preoptic-Basal Forebrain Causes Aging-like Sleep-Wake Disturbances in Young Mice

Sleep disruption is a frequent problem of advancing age, often accompanied by low-grade chronic central and peripheral inflammation. We examined whether chronic neuroinflammation in the preoptic and basal forebrain area (POA-BF), a critical sleep-wake regulatory structure, contributes to this disruption. We developed a targeted viral vector designed to overexpress tumor necrosis factor-alpha (TNFα), specifically in astrocytes (AAV5-GFAP-TNFα-mCherry), and injected it into the POA of young mice to induce heightened neuroinflammation within the POA-BF. Compared to the control (treated with AAV5-GFAP-mCherry), mice with astrocytic TNFα overproduction within the POA-BF exhibited signs of increased microglia activation, indicating a heightened local inflammatory milieu. These mice also exhibited aging-like changes in sleep-wake organization and physical performance, including (a) impaired sleep-wake functions characterized by disruptions in sleep and waking during light and dark phases, respectively, and a reduced ability to compensate for sleep loss; (b) dysfunctional VLPO sleep-active neurons, indicated by fewer neurons expressing c-fos after suvorexant-induced sleep; and (c) compromised physical performance as demonstrated by a decline in grip strength. These findings suggest that inflammation-induced dysfunction of sleep- and wake-regulatory mechanisms within the POA-BF may be a critical component of sleep-wake disturbances in aging.

Handgrip strength is associated with cognitive function in older patients with stage 3-5 chronic kidney disease: results from the NHANES

In this study, we aimed to investigate the association between handgrip strength (HGS) and cognitive performance in stage 3-5 chronic kidney disease (CKD) patients aged ≥ 60 years. This cross-sectional study analyzed data from National Health and Nutrition Examination Survey (NHANES) database 2011-2014. Three tests were used to assess the cognitive performance, including consortium to establish a registry for Alzheimer's disease (CERAD), animal fluency test (AFT), and digit symbol substitution test (DSST). The multivariate linear regression analyses adjusting for confounding factors were utilized to evaluate the association of HGS with cognitive performance. A total of 678 older stage 3-5 CKD patients were included in this study. After adjusting for multiple factors, a higher HGS was positively associated with a higher CERAD-delayed recall and DSST score. In addition, our analysis indicated that HGS probably correlated with better performance of immediate learning ability in male, while working memory, sustained attention, and processing speed in female. HGS may be an important indicator for cognitive deficits in stage 3-5 CKD patients, especially for learning ability and executive function. Further research to explore the sex-specific and domain-specific and possible mechanisms are required.

Predictors of elevated C-reactive protein among pre-treatment, newly diagnosed breast cancer patients: A cross-sectional study

BACKGROUND & AIMS

Accumulating evidence showed that inflammation contributes markedly to cancer progression, with C-reactive protein (CRP) being one of the lengthily studied inflammation marker. For breast cancer (BCa), pre-treatment elevated CRP upon diagnosis was linked with increased mortality. This study aimed to identify factors predictive of elevated CRP in pre-treatment BCa population that can serve as potential therapeutic targets to reduce inflammation.

METHODS

This is a cross-sectional study using multiple logistic regression to identify predictors of elevated CRP among pre-treatment, newly diagnosed BCa patients. Studied variables were socio-demographic and medical characteristics, anthropometric measurements [body weight, Body Mass Index, body fat percentage, fat mass/fat free mass ratio, muscle mass, visceral fat], biochemical parameters [albumin, hemoglobin, white blood cell (WBC), neutrophil, lymphocyte], energy-adjusted Dietary Inflammatory Index, handgrip strength (HGS), scored Patient Generated-Subjective Global Assessment, physical activity level and perceived stress scale (PSS).

RESULTS

A total of 105 participants took part in this study. Significant predictors of elevated CRP were body fat percentage (OR 1.222; 95 % CI 1.099-1.358; p < 0.001), PSS (OR 1.120; 95 % CI 1.026-1.223; p = 0.011), low vs normal HGS (OR 41.928; 95 % CI 2.155-815.728; p = 0.014), albumin (OR 0.779; 95 % CI 0.632-0.960; p = 0.019), and WBC (OR 1.418; 95% CI 1.024-1.963; p = 0.036).

CONCLUSION

Overall, predictors of elevated CRP in pre-treatment, newly diagnosed BCa population were body fat percentage, PSS, HGS category, albumin and WBC.

Gingival bleeding as a predictor of handgrip strength-an observational study and a pilot randomized clinical trial

OBJECTIVE

The aim of this study was to (i) assess the association between self-reported periodontal disease and gingival bleeding as predictors of handgrip strength (HGS) in the elderly and (ii) evaluate the impact of baseline periodontal clinical parameters on the improvement of HGS in trained or non-trained treated periodontitis patients.

METHODS

For (i), cross-sectional data from the Brazilian Longitudinal Study of Aging were retrieved and association between HGS (dependent variable) and self-reported gingival bleeding, periodontal disease, and missing teeth was analyzed using multiple linear regressions. For (ii), a pilot study was conducted with 17 patients randomly allocated to two groups-physical training or non-training-and followed for 45 days after subgingival instrumentation. Clinical parameters and HGS were recorded before and after treatment.

RESULTS

The observational study showed a significant association between HGS and tooth loss, edentulism and gingival bleeding. The clinical trial showed that baseline bleeding on probing, but not other parameters, was associated with delta HGS.

CONCLUSION

Taken together, our findings suggest that gingival bleeding could act as a predictor of handgrip strength and its improvement after non-surgical periodontal therapy.

CLINICAL RELEVANCE

Gingival bleeding, either as self-perceived or clinically detected, may impact handgrip strength, an important marker of muscle frailty and mortality.

Relationship between Lean Tissue Mass and Muscle Function in Women with Obesity

It is well documented that lean tissue mass (LTM) decreases with aging in patients with obesity, but there is no information available regarding muscle strength changes, a parameter that may be better associated with sarcopenic obesity (SO). The objectives of this study were to analyze the changes in LTM and fat mass (FM), muscle strength and muscle function with aging in women with obesity and to determine the prevalence of SO. LTM and FM were determined by DXA, muscle strength with the hand-grip test and muscle function with the 6 min walk test (6MWT) in 383 women with obesity. A redistribution of the LTM and FM occurred with age, characterized by a gain at the trunk to the detriment of the lower limbs, thus reducting in appendicular LTM indices. The physical performances evaluated by the muscle strength and muscle function decreased concomitantly, and the prevalence of low values for both these parameters was 22.8% and 13.4%, respectively, in the older patients. In summary, although a reduction in appendicular LTM and muscle performances occurred with age and resulted in an increase in the prevalence of SO, the number of women with obesity affected by SO remained low (n ≤ 15), even in those older than 60 years.

Handgrip Strength Is Related to Hippocampal and Lobar Brain Volumes in a Cohort of Cognitively Impaired Older Adults with Confirmed Amyloid Burden

BACKGROUND

Strength and mobility are essential for activities of daily living. With aging, weaker handgrip strength, mobility, and asymmetry predict poorer cognition. We therefore sought to quantify the relationship between handgrip metrics and volumes quantified on brain magnetic resonance imaging (MRI).

OBJECTIVE

To model the relationships between handgrip strength, mobility, and MRI volumetry.

METHODS

We selected 38 participants with Alzheimer's disease dementia: biomarker evidence of amyloidosis and impaired cognition. Handgrip strength on dominant and non-dominant hands was measured with a hand dynamometer. Handgrip asymmetry was calculated. Two-minute walk test (2MWT) mobility evaluation was combined with handgrip strength to identify non-frail versus frail persons. Brain MRI volumes were quantified with Neuroreader. Multiple regression adjusting for age, sex, education, handedness, body mass index, and head size modeled handgrip strength, asymmetry and 2MWT with brain volumes. We modeled non-frail versus frail status relationships with brain structures by analysis of covariance.

RESULTS

Higher non-dominant handgrip strength was associated with larger volumes in the hippocampus (p = 0.02). Dominant handgrip strength was related to higher frontal lobe volumes (p = 0.02). Higher 2MWT scores were associated with larger hippocampal (p = 0.04), frontal (p = 0.01), temporal (p = 0.03), parietal (p = 0.009), and occipital lobe (p = 0.005) volumes. Frailty was associated with reduced frontal, temporal, and parietal lobe volumes.

CONCLUSION

Greater handgrip strength and mobility were related to larger hippocampal and lobar brain volumes. Interventions focused on improving handgrip strength and mobility may seek to include quantified brain volumes on MR imaging as endpoints.

Sarcopenia and Frailty in Heart Failure: Is There a Biomarker Signature?

PURPOSE OF REVIEW

Sarcopenia and frailty are common in patients with heart failure (HF) and are strongly associated with prognosis. This review aims to examine promising biomarkers that can guide physicians in identifying sarcopenia and frailty in HF.

RECENT FINDINGS

Traditional biomarkers including C-reactive protein, aminotransaminase, myostatin, and urinary creatinine as well as novel biomarkers including microRNAs, suppression of tumorigenicity 2 (ST2), galectin-3, and procollagen type III N-terminal peptide may help in predicting the development of sarcopenia and frailty in HF patients. Among those biomarkers, aminotransferase, urinary creatinine, and ST2 predicted the prognosis in HF patients with sarcopenia and frailty. This review outlines the current knowledge of biomarkers that are considered promising for diagnosing sarcopenia and frailty in HF. The listed biomarkers might support the diagnosis, prognosis, and therapeutic decisions for sarcopenia and frailty in HF patients.

Handgrip weakness, systemic inflammation indicators, and overall survival in lung cancer patients with well performance status: A large multicenter observational study

BACKGROUND

Systemic inflammation and handgrip weakness have been used to predict mortality in many cancers. The purpose of current study was to evaluate the association of co-occurrence of inflammation indicators and handgrip weakness with overall survival (OS) of lung cancer (LC) patients with good performance status.

METHODS

The cutoff points for handgrip strength (HGS) and the four inflammation indicators were calculated using Maxstat. The time-dependent receiver operating characteristic curve and C-index were used to select optimal inflammation indicator for predicting OS of LC patients. The Cox proportional hazard regression model was used to calculate the hazard ratio (HR) of mortality. Kaplan-Meier curves were constructed to evaluate the association of indicators and the OS of LC patients.

RESULTS

Among the 1951 patients, the mean ± standard deviation (SD) age was 60.6 ± 9.9 years, and 1300 (66.6%) patients were male. In patients with good performance status (PS), handgrip weakness (HR, 1.49; 95% confidence interval [95% CI], 1.30-1.70, p < 0.001) and low advanced lung cancer inflammation index (ALI) (HR, 2.05; 95%CI, 1.79-2.34, p < 0.001), high systemic immune-inflammation index (SII) (HR, 1.91; 95%CI, 1.66-2.19, p < 0.001), high platelet: lymphocyte ratio (PLR) (HR, 1.60; 95%CI, 1.40-1.82, p < 0.001), or high neutrophil: lymphocyte ratio (NLR) (HR, 2.01; 95%CI, 1.76-2.30, p < 0.001) were associated with increased mortality risk of LC patients. ALI had better C-index (0.624) and time-AUC in the prediction of OS in LC patients with good PS than other three combinations. The co-occurrence of handgrip weakness and low ALI more than doubled the risk of death in LC with good PS (HR, 2.44; 95% CI, 2.06-2.89, p < 0.001).

CONCLUSION

In LC patients who have good PS, patients with combined handgrip weakness and low ALI have the worst prognosis.

THE TRIAL REGISTRATION NUMBER

ChiCTR1800020329.

Muscle weakness as an additional criterion for grading sarcopenia-related prognosis in patients with cancer

Background

Low muscle strength has been pointed out as a key characteristic of sarcopenia, but the prognostic significance of muscle function next to reduced skeletal muscle mass (SMM) in patients with cancer has been scantily investigated.

Methods

Data on muscle strength by handgrip (HG) dynamometry and total‐body SMM estimated by bioelectrical impedance analysis (BIA) of Italian and German patients with cancer observed prospectively until death or censoring were analysed (N = 1076). Patients were stratified in four risk categories based on low HG (<10th percentiles of age and gender‐specific normative values) and low total‐body SMM according to SMM index cutoffs (<10.75 and <6.75 kg/m² in men and women, respectively).

Results

During a median follow‐up of 58 months [25th–75th percentile, 37–60], 566 patients had died. Patients presenting low HG in combination or not with low SMM were characterised by shorter median survival (12.7 vs. 27.2 months, respectively; p < 0.001) compared to those with low SMM/normal HG and normal SMM/normal HG (>60 months for both). After adjusting for sex, age, body mass index and percentage of weight loss, disease's stage, performance status and type of cancer, compared to reference category (normal HG and SMM; N = 210) the hazard ratios were: low SMM/normal HG (N = 342), 0.83 [95% confidence interval, CI, 0.67–1.02] (p = 0.073); normal SMM/low HG (N = 158), 1.19 [95% CI, 1.07–1.32] (p = 0.002); low SMM/low HG (N = 366), 1.39 [95% CI, 1.27–1.53] (p < 0.001).

Conclusions

Muscle weakness was found to be a more powerful predictor of survival than BIA‐estimated SMM and should be considered as an additional key feature of sarcopenia in patients with cancer.

Low muscle strength has been pointed out as a key characteristic of sarcopenia, but the prognostic significance of muscle function next to reduced skeletal muscle mass (SMM) in patients with cancer has been scantily investigated. Muscle weakness was found to be a more powerful predictor of survival than SMM and should be considered as additional key feature of sarcopenia in patients with cancer.

Comparisons and Impacts of the Basic Components of Sarcopenia Definition and Their Pairwise Combinations in Gastric Cancer: A Large-Scale Study in a Chinese Population

Background and Aims: Sarcopenia is negatively associated with clinical outcomes. However, the definitions of sarcopenia are inconsistent across international consensuses. Thus, the purpose of this study is to compare the impact of the basic definition components of sarcopenia and their combinations in post-operative complications and overall survival, aiming to find the best sarcopenia definition to stratify the prognosis in an Asian population.

Methods: A total of 1,307 patients who underwent curative surgery for gastric cancer from July 2014 to May 2019 were prospectively included. The basic sarcopenia components were measured pre-operatively, including low skeletal muscle mass index (LSMI), low skeletal muscle radiodensity (LSMD), low handgrip strength (LHGS), and low gait speed (LGS). Among them, LSMI and LSMD were measured using a CT post-processing software, LHGS was measured using an electronic hand dynamometer, and LGS was represented by a 6-m walk speed.

Results: For the single basic component, the muscle function parameters (LHGS or LGS) but not the muscle composition parameters (LSMI or LSMD) showed associations with post-operative complications and mortality. For the combination of the basic combinations, all statistically significant combinations included at least one muscle function parameter. The combination of muscle composition (LSMI or LSMD) and muscle function (LHGS or LGS) had a significantly higher area under the curve in the prediction of post-operative complications compared with the combinations of two muscle function parameters (LSMI plus LSMD) or two muscle composition parameters (LHGS plus LGS).

Conclusions: Compared with muscle composition parameters (LSMI and LSMD), muscle function parameters (LHGS and LGS) are better predictors of post-operative complications and overall survival, which should be considered as the principal determinant in the sarcopenia definition. The definition of sarcopenia consists of muscle function (LHGS or LGS) and muscle composition (LSMI or LSMD) separately, which is better than the combination of the two muscle function parameters (LHGS plus LGS) or two muscle composition parameters (LSMI plus LSMD).

Low hand grip strength is associated with worse functional capacity and higher inflammation in people receiving maintenance hemodialysis

OBJECTIVES

To evaluate the associations of hand grip strength (HGS) with body composition, functional capacity, muscle quality, and inflammatory markers in people receiving maintenance hemodialysis.

METHODS

This is a cross-sectional study in people receiving maintenance hemodialysis. HGS was measured by hydraulic dynamometer on the upper limb without fistula. Participants were stratified into low or adequate HGS, based on population-specific cutoff points. Body composition was assessed by dual-energy X-ray absorptiometry, and functional capacity by the Short Physical Performance Battery and timed up-and-go tests. In addition, serum creatinine, interleukin-6 (IL-6), IL-10, tumor necrosis factor-α, and ultra-sensitive C-reactive protein (us-CRP) were measured before the dialysis session.

RESULTS

A total of 67 participants (41.8% women, 58.2% male; ages 54.1 ± 11.7 y) were included. Those with low HGS had worse functional capacity than those with adequate HGS (timed up-and-go test, 10.7 ± 1.0 versus 8.5 ± 0.8 sec, respectively; P < 0.001). IL-6 and us-CRP were higher in those with low HGS than their counterparts (IL-6: 2.7 ± 0.3 versus 1.9 pg/mL, P = 0.03; us-CRP: 14.8 ± 3.0 versus 4.7 ± 1.9 mg/L, P = 0.03). Multiple linear regression analysis showed that appendicular lean mass, us-CRP, age, sex, and seven-point subjective global assessment score were associated with HGS.

CONCLUSIONS

Participants with low HGS showed higher inflammation and lower functional capacity. In addition to muscle mass, inflammation and nutritional status also affect HGS.<END ABSTRACT>.

Hospitalization-associated muscle weakness and functional outcomes among oldest old patients: A hospital-based cohort study

AIM

To investigate the prognostic significance of hospitalization-associated muscle weakness for short-term and long-term functional declines among oldest old hospitalized patients.

METHODS

We conducted a retrospective cohort study in the Geriatric Evaluation and Management Unit (GEMU) of a tertiary medical center in Taiwan. Data from patients admitted to the GEMU were collected, including demographic characteristics, underlying diseases, functional assessments, and nutritional status. Handgrip strength was measured at admission and before discharge, and hospitalization-associated muscle weakness was defined accordingly. Functional status was ascertained by a telephone survey, and functional decline was defined based on a comparison with each patient's functional status before discharge.

RESULTS

Overall, data from 555 patients were retrieved, and 431 patients (mean age: 86.0 ± 6.2 years, 78.5% males) were included in the study, with a mean Barthel Index score of 74.7 ± 20.8, Mini-Mental State Examination (MMSE) score of 19.1 ± 6.8, Geriatric Depression Scale (GDS-5) score of 2.2 ± 1.6, Mini-Nutritional Assessment-Short Form (MNA-SF) score of 8.9 ± 3.0, Cumulative Illness Rating Scale-Geriatric (CIRS-G) score of 2.2 ± 0.9, and the regular use of 6.7 ± 3.5 medications. Patients with a 1-month postdischarge functional decline had significantly lower body weight and body mass index, more severe frailty and more hospitalization-associated muscle weakness. Patients with a 6-month postdischarge functional decline had lower body weight, BMI, MMSE scores, MNA-SF scores, handgrip strength, Barthel Index scores, and Braden Scale scores. BMI (OR: 0.815, 95% CI: 0.691-0.962, P = 0.015) and hospitalization-associated muscle weakness (OR: 1.227, 95% CI: 1.147-1.332, P < 0.001) were significantly associated with a 1-month postdischarge functional decline. Hospitalization-associated muscle weakness (OR: 1.067, 95% CI: 1.035-1.101, P < 0.001), the risk of pressure sores (Braden Scale, OR: 0.767, 95% CI: 0.646-0.910, P = 0.002), and BMI (OR: 0.914, 95% CI: 0.838-0.998, P = 0.045) were independently associated with a 6-month postdischarge functional decline.

CONCLUSIONS

Hospitalization-associated muscle weakness significantly predicts functional decline among oldest old patients hospitalized for acute conditions. Further interventional studies are needed to examine the causal relationship between hospitalization-associated muscle weakness and clinical outcomes.

Association of circulating C-reactive protein and high-sensitivity C-reactive protein with components of sarcopenia: A systematic review and meta-analysis of observational studies

BACKGROUND

Sarcopenia, a multi-faceted skeletal muscle disorder in the older population, has poor health outcomes. Some previous observational studies investigated the association between circulating inflammatory markers and sarcopenia components to evaluate chronic inflammation as a risk factor for sarcopenia in the elderly population. Nevertheless, the association between circulating C-reactive protein (CRP) and hs-CRP, as the recognized markers of systemic inflammation and components of sarcopenia, is unclear. This meta-analysis aimed to investigate the association of muscle strength, muscle mass, and muscle function with two serum inflammatory markers, circulating C-reactive protein (CRP) and high-sensitive CRP (hs-CRP).

METHODS

We assessed all observational studies across different electronic databases including PubMed, Scopus, and Google Scholar using keywords such as "muscle strength", "muscle mass", "muscle function", CRP and hs-CRP from inception until the 30th of July 2019. Only studies that investigated the association between components of sarcopenia and CRP or hs-CRP levels were included. Participants' country, age, sex, BMI, and screening tool for sarcopenia were retrieved. The correlations between muscle strength, muscle mass, and muscle function with CRP, and hs-CRP were expressed as the correlation coefficient (r) with 95% confidence intervals (CIs). Begg's test and Egger's test were conducted to evaluate risk of publication bias in this study.

RESULTS

Initially, we found fifty-nine studies for the qualitative synthesis. Ultimately, nineteen adult cross-sectional studies comprising 14,650 subjects were included in the meta-analysis. Of them, fourteen studies measured the correlation between CRP or hs-CRP and muscle strength. There were significant inverse correlation between CRP and hs-CRP concentrations with muscle strength (ES (z) = -0.22; 95% CI = -0.34 to -0.09; P < 0.001), (ES (z) = -0.22; 95% CI = -0.34 to -0.09; P < 0.001), respectively. No publication bias was found between muscle strength and CRP (P = 0.53) or hs-CRP (P = 0.62) respectively.

CONCLUSION

Among diagnostic components of sarcopenia, impairment of muscle strength was independently associated with both inflammatory biomarkers. However, future cohort studies are essential to clarify the causal correlation.

Inflammation Mediates Exercise Effects on Fatigue in Patients with Breast Cancer

PURPOSE

The randomized controlled OptiTrain trial showed beneficial effects on fatigue after a 16-wk exercise intervention in patients with breast cancer undergoing adjuvant chemotherapy. We hypothesize that exercise alters systemic inflammation and that this partially mediates the beneficial effects of exercise on fatigue.

METHODS

Two hundred and forty women scheduled for chemotherapy were randomized to 16 wk of resistance and high-intensity interval training (RT-HIIT), moderate-intensity aerobic and high-intensity interval training (AT-HIIT), or usual care (UC). In the current mechanistic analyses, we included all participants with >60% attendance and a random selection of controls (RT-HIIT = 30, AT-HIIT = 27, UC = 29). Fatigue (Piper Fatigue Scale) and 92 markers (e.g., interleukin-6 [IL-6] and tumor necrosis factor α [TNF-α]) were assessed at baseline and postintervention. Mediation analyses were conducted to explore whether changes in inflammation markers mediated the effect of exercise on fatigue.

RESULTS

Overall, chemotherapy led to an increase in inflammation. The increases in IL-6 (pleiotropic cytokine) and CD8a (T-cell surface glycoprotein) were however significantly less pronounced after RT-HIIT compared with UC (-0.47, 95% confidence interval = -0.87 to -0.07, and -0.28, 95% confidence interval = -0.57 to 0.004, respectively). Changes in IL-6 and CD8a significantly mediated the exercise effects on both general and physical fatigue by 32.0% and 27.7%, and 31.2% and 26.4%, respectively. No significant between-group differences in inflammatory markers at 16 wk were found between AT-HIIT and UC.

CONCLUSIONS

This study is the first showing that supervised RT-HIIT partially counteracted the increase in inflammation during chemotherapy, i.e., IL-6 and soluble CD8a, which resulted in lower fatigue levels postintervention. Exercise, including both resistance and high-intensity aerobic training, might be put forward as an effective treatment to reduce chemotherapy-induced inflammation and subsequent fatigue.

Decreased Appendicular Skeletal Muscle Mass is Associated with Poor Outcomes after ST-Segment Elevation Myocardial Infarction

AIM

The importance of sarcopenia in cardiovascular diseases has been recently demonstrated. This study aims to examine whether skeletal muscle mass (SMM), an important component of sarcopenia, is associated with an increased risk of poor outcome in patients after ST-segment elevation myocardial infarction (STEMI).

METHODS

We measured SMM in 387 patients with STEMI using dual-energy X-ray absorptiometry. Patients were divided into low- and high-appendicular skeletal mass index (ASMI: appendicular SMM divided by height squared (kg/m²)) groups using the first quartile of ASMI (≤ 6.64 kg/m² for men and ≤ 5.06 kg/m² for women). All patients were followed up for the primary composite outcome of all-cause death, nonfatal myocardial infarction, nonfatal ischemic stroke, hospitalization for congestive heart failure, and unplanned revascularization.

RESULTS

Low-ASMI group was older and had a more complex coronary lesion, a lower left ventricular ejection fraction, and a higher prevalence of Killip classification ≥ 2 than high-ASMI group. During a median follow-up of 33 months, the event rate was significantly higher in low-ASMI group than in high-ASMI group (24.7% vs 13.4%, log-rank p=0.001). Even after adjustment for patients' background, low ASMI was independently associated with the high risk of primary composite events (adjusted hazard ratio 2.06, 95% confidence interval 1.01- 4.19, p=0.04). In the subgroup analyses of male patients (n=315), the optimal cutoff point of ASMI for predicting primary composite outcome was 6.75 kg/m², which was close to its first quartile value.

CONCLUSIONS

Low ASMI is independently associated with poor outcome in patients with STEMI.

Relationship between oral health behaviour and handgrip strength: a cross-sectional study with 7589 Korean adults

Objective: This cross-sectional study investigated the relationship between handgrip strength and oral health behaviours among Koreans.Methods: The data of 7589 individuals (3384 men and 4205 women) aged ≥19 years who participated in the Korea National Health and Nutrition Examination Survey 2014-2015 were analyzed. Oral health behaviour was assessed based on the number of daily toothbrushing sessions and the use of secondary oral-care products. The association between oral-health behaviour and handgrip strength was investigated adjusting for confounders. Multivariable logistic regression analysis was performed (α = 0.05).Results: The proportion of participants diagnosed with sarcopenia was significantly higher in the group with poor oral-health behaviours. After adjusting for confounders including age, the adjusted odds ratios and 95% confidence intervals of female participants with low handgrip strength in groups toothbrushing thrice or more per day, twice per day, and once or less per day were 1 (reference), 1.18 (0.99-1.4), and 1.24 (0.89-1.71), respectively. There were significantly more participants with low handgrip strength in the group that did not use secondary oral products for both sexes.Conclusions: Oral health behaviour is associated with handgrip strength among adults. Poor oral self-care habits may constitute a risk indicator for low muscle strength.

Prediction and discrimination of skeletal muscle function by bioelectrical impedance vector analysis using a standing impedance analyzer in healthy Taiwanese adults

Background

Bioelectrical impedance vector analysis (BIVA) has been used for prediction of muscle performance. However, little is known about BIVA in Asian adults, and even less is known about using standing BIVA devices. Standing impedance analyzer allows quicker and more convenient way to gather data than conventional supine analyzer and is more suitable for clinical practice. This study aimed to investigate the relations between muscle function and BIVA parameters measured with a standing impedance analyzer in healthy Taiwanese adults.

Methods

A total of 406 healthy subjects (age 34.5 ± 17.3 years, body mass index 24.1 ± 4.1 kg/m²) were recruited for BIVA and handgrip strength (HGS) measurements. Impedance parameters, including resistance (R) and reactance (Xc), were measured and normalized to body size by dividing by height (H). The resulting phase angle (PhA) was calculated. HGS in the dominant, left, and right hands were referred to as HGS_DH, HGS_LH, and HGS_RH, respectively. All subjects were divided into 5 grades according to HGS.

Results

Muscle strength in the dominant, right, and left arms was correlated with variables in the order of sex, weight, age, height, Xc/H, and R/H (all, p < 0.001). Using all 6 variables, the determination coefficients were 0.792, 0.782, and 0.745, respectively, whereas the standard errors of estimates were 56.89, 58.01, and 56.67 N for HGS_DH, HGS_LH, and HGS_RH, respectively. HGS was positively correlated with PhA, and negatively correlated with Xc/H and R/H.

Conclusions

BIVA parameters measured with a standing impedance analyzer and anthropometric variables can predict and discriminate muscle function with good performance in healthy Asian adults.

Association of 10-Year C-Reactive Protein Trajectories With Markers of Healthy Aging: Findings From the English Longitudinal Study of Aging

Background

Elevated systematic inflammation is a hallmark of aging, but the association of long-term inflammation trajectories with subsequent aging phenotypes has been little examined. We assessed inflammatory marker C-reactive protein (CRP) repeatedly over time and examined whether long-term changes predicted aging outcomes.

Methods

A total of 2,437 men and women aged 47–87 years at baseline (1998–2001) who were participants in the English Longitudinal Study of Ageing had CRP measured on two or three occasions between 1998 and 2009. Inflammation trajectories were computed using latent-class growth mixture modeling and were related to aging outcomes measured in 2012/2013: physical functioning, cardiometabolic, respiratory, mental health, and a composite “healthy aging” outcome.

Results

Four CRP trajectories were identified as follows: “stable-low” (71 per cent of the sample) with baseline mean 1.33 mg/L remaining <3 mg/L; “medium-to-high” (14 per cent) with baseline 2.7 mg/L rising to 5.3 mg/L; “high-to-medium” (10 per cent) with baseline 6.6 mg/L decreasing to 2.4 mg/L; and “stable-high” (5 per cent) with levels from 5.7 to 7.5 mg/L. Relative to the stable-low trajectory, individuals in the medium-to-high had a higher risk of limitations in basic activities of daily living (ADL, odds ratio; 95% confidence interval: 2.09; 1.51, 2.88), instrumental ADL (1.62; 1.15, 2.30), impaired balance (1.59; 1.20, 2.11) and walking speed (1.61; 1.15, 2.24), arthritis (1.55; 1.16, 2.06), hypertension (1.57; 1.21, 2.04), obesity (1.95; 1.36, 2.80), poor respiratory function (1.84; 1.36, 2.50), and depression (1.55; 1.13, 2.12). A lower odds of healthy aging was observed in people in the medium-to-high (0.57; 0.40, 0.79) and stable-high (0.50; 0.27, 0.91) trajectories.

Conclusions

Older people who displayed an elevation in CRP levels over a decade experienced an increased risk of adverse aging outcomes.

Early mobilization of critically ill patients in the intensive care unit: A systematic review and meta-analysis

BACKGROUND

Physical therapy can prevent functional impairments and improve the quality of life of patients after hospital discharge. However, the effect of early mobilization on patients with a critical illness remains unclear. This study was performed to assess the evidence available regarding the effect of early mobilization on critically ill patients in the intensive care unit (ICU).

METHODS

Electronic databases were searched from their inception to March 21, 2019. Randomized controlled trials (RCTs) comprising critically ill patients who received early mobilization were included. The methodological quality and risk of bias of each eligible trial were assessed using the Cochrane Collaboration tool. Data were extracted using a standard collection form each included study, and processed using the Mantel-Haenszel (M-H) or inverse-variance (I-V) test in the STATA v12.0 statistical software.

RESULTS

A total of 1,898 records were screened. Twenty-three RCTs comprising 2,308 critically ill patients were ultimately included. Early mobilization decreased the incidence of ICU-acquired weakness (ICU-AW) at hospital discharge (three studies, 190 patients, relative risk (RR): 0.60, 95% confidence interval (CI) [0.40, 0.90]; p = 0.013, I2 = 0.0%), increased the number of patients who were able to stand (one study, 50 patients, 90% vs. 62%, p = 0.02), increased the number of ventilator-free days (six studies, 745 patients, standardized mean difference (SMD): 0.17, 95% CI [0.02, 0.31]; p = 0.023, I2 = 35.5%) during hospitalization, increased the distance the patient was able to walk unassisted (one study, 104 patients, 33.4 (0-91.4) meters vs. 0 (0-30.4) meters, p = 0.004) at hospital discharge, and increased the discharged-to-home rate (seven studies, 793 patients, RR: 1.16, 95% CI [1.00, 1.34]; p = 0.046). The mortality (28-day, ICU and hospital) and adverse event rates were moderately increased by early mobilization, but the differences were statistically non-significant. However, due to the substantial heterogeneity among the included studies, and the low quality of the evidence, the results of this study should be interpreted with caution. Publication bias was not identified.

CONCLUSIONS

Early mobilization appears to decrease the incidence of ICU-AW, improve the functional capacity, and increase the number of ventilator-free days and the discharged-to-home rate for patients with a critical illness in the ICU setting.

Analysis of functional status and muscle strength in adults and older adults in an intensive care unit: a prospective cohort study

The aim of this study was to analyze and assess the association between functional status (FS) and muscle strength (MS) in young adults, adults and older adults in an intensive care unit (ICU). We conducted a prospective cohort study with 48 patients. FS was assessed using the Functional Status Score for the Intensive Care Unit (FSS-ICU) and MS was measured using the Medical Research Council Sum-Score (MRC-SS) and by testing handgrip strength (HS). The assessments were performed on awakening and ICU discharge. The data were analyzed using the Kruskall-Wallis, chi-squared, Wilcoxon and Spearman's correlation tests. FS and MRC-SS scores were higher on ICU discharge in all groups. Gains were lowest in the older adult group. HS was greater in both hands on ICU discharge in all groups except the adults. FSS-ICU on both awakening and ICU discharge was highest in the adults; HS-R was lowest in the older adults. There was a strong association between FS and MS in the young adults and adults. FS and MS showed progressive improvement during ICU stay. Gains in FS and MS on awakening and ICU discharge were lowest among the older adults. Important associations were found between these variables in all groups except the older adults. This can be explained by the multifactorial nature of illness and incapacity in this group.

Assessing cachexia in older patients: Different definitions - But which one is the most practical for clinical routine?

OBJECTIVE

Patients with chronic inflammatory diseases and malignant tumors have an increased risk of cachexia. No consistent definition exists to rapidly identify cachexia in older patients with and without cancer.

METHODS

One-hundred patients (53% male) aged 70 +  years were included in the study by a university hospital. In addition to the detection of malnutrition and determination of body composition by bioelectrical impedance analysis, cachexia was assessed according to the well-established definitions of Evans (weight loss ≥ 5% within the last 12 months plus additional clinical parameters), Fearon (weight loss > 5% in 6 months) and Bozzetti (weight loss ≥ 10% of habitual weight). After a follow-up of 3.5 years, the mortality rate was recorded.

RESULTS

Thirty-three patients had a malignant tumor disease. The patients with a non-malignant underlying disease did not differ in their mental state, physical condition and state of health compared to patients with cancer. A higher percentage of patients with underlying malignancy had cachexia. There were significant differences in the body composition between the patients with or without cachexia. Cachectic patients exhibited a significantly lower skeletal muscle mass and fat mass. The risk of death was increased in cachectic patients of all three cachexia definitions.

CONCLUSION

For clinical daily routine, the assessments by a weight loss according to Fearon and Bozzetti are suggested to be practicable methods to detect cachexia in older patients with and without cancer.

Racial differences in inflammation and outcomes of aging among kidney transplant candidates

Background

Inflammation is more common among African Americans (AAs), and it is associated with frailty, poor physical performance, and mortality in community-dwelling older adults. Given the elevated inflammation levels among end-stage renal disease (ESRD) patients, inflammation may be associated with adverse health outcomes such as frailty, physical impairment, and poor health-related quality of life (HRQOL), and these associations may differ between AA and non-AA ESRD patients.

Methods

One thousand three ESRD participants were recruited at kidney transplant evaluation (4/2014–5/2017), and inflammatory markers (interleukin-6 [IL-6], tumor necrosis factor-a receptor-1 [TNFR1], C-reactive protein [CRP]) were measured. We quantified the association with frailty (Fried phenotype), physical impairment (Short Physical Performance Battery [SPPB]), and fair/poor HRQOL at evaluation using adjusted modified Poisson regression and tested whether these associations differed by race (AA vs. non-AA).

Results

Non-AAs had lower levels of TNFR1 (9.7 ng/ml vs 14.0 ng/ml, p < 0.001) and inflammatory index (6.7 vs 6.8, p < 0.001) compared to AAs, but similar levels of IL-6 (4.5 pg/ml vs 4.3 pg/ml, p > 0.9) and CRP (4.7 μg/ml vs 4.9 μg/ml, p = 0.4). Non-AAs had an increased risk of frailty with elevated IL-6 (RR = 1.58, 95% CI:1.27–1.96, p < 0.001), TNFR1 (RR = 1.60, 95% CI:1.25–2.05, p < 0.001), CRP (RR = 1.41, 95% CI:1.10–1.82, p < 0.01), and inflammatory index (RR = 1.82, 95% CI:1.44–2.31, p < 0.001). The associations between elevated inflammatory markers and frailty were not present among AAs. Similar results were seen with SPPB impairment and poor/fair HRQOL.

Conclusions

Non-AAs with elevated inflammatory markers may need closer follow-up and may benefit from prehabilitation to improve physical function, reduce frailty burden, and improve quality of life prior to transplant.

Association of cognitive impairment and grip strength trajectories with mortality among middle-aged and elderly adults

ABSTRACTBackground:This study investigates whether maintaining high levels of cognitive impairment and weak grip strength will predict a higher risk for mortality.

METHODS

Data from the Korean Longitudinal Study of Aging (KLoSA) from 2006 to 2014 was assessed using longitudinal data analysis and included 5,812 research subjects. Our modeling approach jointly estimated multi-period trajectories of grip strength and cognitive impairment, and the primary analysis was based on Cox proportional hazards models.

RESULTS

A four-class linear solution fit the data best in both cognitive impairment and grip strength based on the model fitness, respectively. The hazard ratio (HR) of mortality in group 1 (consistently low) of cognitive impairment and of grip strength were 2.114 times higher (p-value 0.001) and 3.405 times higher (p-value &lt;.0001) compared with group 3 (consistently high) and group 4 (consistently high), respectively.

CONCLUSION

This study provides insightful scientific evidence into the specificity of longitudinal changes in grip strength and cognitive impairment on mortality. Our findings suggest that declined cognitive ability and weak grip strength are predictors of mortality in older Korean people.

Acute inflammation is associated with lower muscle strength, muscle mass and functional dependency in male hospitalised older patients

Background

Hospitalisation is associated with adverse health outcomes including loss of muscle strength, muscle mass and functional decline, which might be further aggravated by acute inflammation. This study aimed to determine whether acute inflammation, as denoted by C-reactive protein (CRP), is associated with muscle strength, muscle mass and functional dependency in hospitalised older patients.

Methods

The observational, prospective EMPOWER study included 378 hospitalised patients aged 70 years and older. As part of the hospital assessment, 191 patients (50.5%) had CRP measured. Muscle strength and mass were measured using handheld dynamometry and bioelectrical impedance analysis respectively. Activities of Daily Living (ADL) were assessed using Katz score and Instrumental ADL (IADL) by Lawton and Brody score. Linear regression analyses and logistic regression analyses were performed stratified by sex and adjusted for age and comorbidities.

Results

Mean age was 79.7 years (SD 6.4) and 50.8% were males. On admission and discharge, males with elevated CRP had significantly lower handgrip strength and lower absolute muscle mass compared with males with normal CRP and those with no CRP measured. At three months post-discharge, males with elevated CRP were more likely to be ADL dependent than those with normal CRP and with no CRP measured. In females, no associations were found between CRP and muscle strength, muscle mass, ADL or IADL.

Conclusions

Hospitalised older male patients with acute inflammation had lower muscle strength at admission and discharge and lower absolute muscle mass at admission and higher ADL dependency at three months post-discharge.

The added value of ultrasound muscle measurements in patients with COPD: An exploratory study

BACKGROUND AND AIMS

Malnutrition and sarcopenia are common nutrition (-related) disorders in patients with COPD and are associated with negative health outcomes and mortality. This study aims to correlate ultrasound measured rectus femoris size with fat-free mass and muscle function in patients with COPD.

METHODS

Patients with COPD, at the start of a pulmonary rehabilitation program, were asked to participate in this study. Rectus femoris (RF) size (thickness in cm, cross-sectional area [CSA] in cm²) was determined by ultrasound. Fat-free mass index (FFMI in kg/m²) was estimated with bioelectrical impedance analyses, using a disease-specific equation. Handgrip strength (HGS) was measured in kilograms and the five times sit to stand test (in seconds, higher scores indicating decreased strength) was performed to assess leg muscle power. The Incremental Shuttle Walk Test (ISWT, in m) was used to assess maximal exercise capacity.

RESULTS

In total, 44 patients with COPD (mean age 59.8 ± 8.6 years, 43% male, median FEV1%pred 37 [IQR = 23-52]) were included. Greater RF-CSA and thickness were associated with higher FFMI (r = 0.57, p < 0.001; r = 0.53, p = 0.003, respectively) and HGS (CSA r = 0.58, p < 0.001, thickness r = 0.48, p = 0.009). No significant correlations between RF-thickness, CSA, and leg muscle power were found (r = -0.33, p = 0.091; r = -0.35, p = 0.073, respectively). Furthermore, no correlation between RF size and maximal exercise capacity was observed (thickness r = 0.21, p = 0.297, CSA r = 0.22, p = 0.274).

CONCLUSIONS

This exploratory study shows that in patients with COPD, rectus femoris size is moderately correlated with FFMI and HGS. Future studies should focus on the role of ultrasound in evaluating nutritional status.

Age-related changes in skeletal muscle: changes to life-style as a therapy

As we age, there is an age-related loss in skeletal muscle mass and strength, known as sarcopenia. Sarcopenia results in a decrease in mobility and independence, as well as an increase in the risk of other morbidities and mortality. Sarcopenia is therefore a major socio-economical problem. The mechanisms behind sarcopenia are unclear and it is likely that it is a multifactorial condition with changes in numerous important mechanisms all contributing to the structural and functional deterioration. Here, we review the major proposed changes which occur in skeletal muscle during ageing and highlight evidence for changes in physical activity and nutrition as therapeutic approaches to combat age-related skeletal muscle wasting.

Relationships Between Markers of Inflammation and Muscle Mass, Strength and Function: Findings from the Hertfordshire Cohort Study

We investigated the longitudinal relationships between inflammation markers and the following outcomes in a UK cohort study: appendicular lean mass (ALM); walking speed; level and change in grip strength; and sarcopenia defined by the European Working Group on Sarcopenia in Older People. Analyses were based on 336 community-dwelling older men and women (aged 59-70 years) who participated in the Hertfordshire Cohort Study (HCS). Inflammation markers were ascertained at baseline using enzyme-linked immunosorbent assay techniques and Bio-Plex Pro Assays. Grip strength was measured at baseline and follow-up [median follow-up time: 10.8 years (inter-quartile range 10.2-11.6)] and change in grip strength was ascertained using a residual change approach. At follow-up, ALM was ascertained using dual-energy X-ray absorptiometry, customary walking speed was measured and sarcopenia status was ascertained. Gender-adjusted linear and Poisson regression was used to examine the associations between inflammation markers and outcomes with and without adjustment for anthropometric and lifestyle factors. Higher C-reactive protein was associated (p < 0.04) with lower grip strength and accelerated decline in grip strength from baseline to follow-up. Higher cortisol was associated with lower ALM (p < 0.05). Higher interleukin-8 (IL-8) was associated with lower ALM (p < 0.05) and increased risk of sarcopenia [fully-adjusted relative risk per SD increase in IL-8: 1.37 (95% CI 1.10, 1.71), p = 0.005]. All associations were robust in fully-adjusted analyses. Inflammation markers were associated with measures of muscle mass, strength and function in HCS. Further work is required to replicate these associations and to delineate the underlying mechanisms.

Does peripheral arterial occlusive disease influence muscle strength and exercise capacity in COPD patients?

Background

The pathophysiology of chronic obstructive pulmonary disease (COPD) is complex and understanding of it has been changing in recent years, with regard to its multisystemic manifestations, especially peripheral dysfunction and its influence on intolerance to exercise.

Objectives

To evaluate the relationship between peripheral arterial occlusive disease (PAOD) and peripheral muscle strength and exercise capacity in COPD patients.

Methods

We conducted a cross-sectional study of 35 patients with COPD who were evaluated with the Ankle-Brachial Index, handgrip strength test, 1 repetition maximum (1RM) of knee extensors and flexors, and distance covered in the incremental shuttle walking test (dISWT).

Results

COPD patients with coexisting PAOD had lower dominant handgrip strength test results (33.00 vs. 26.66 kgf, p = 0.02) and worse performance in the dISWT (297.32 vs. 219.41 m, p = 0.02) when compared to the COPD patients without PAOD. Strong correlations were found between the result of the handgrip strength test and both the dISWT (r = 0.78; p < 0.001) and the 1RM/knee extension (r = 0.71; p = 0.03); and also between the dISWT and both the 1RM/knee extension (r = 0.72; p = 0.02) and the 1RM/knee flexion (r = 0.92; p < 0.001). The linear regression model showed that the dISWT variable alone explains 15.3% of the Ankle-Brachial Index result (p = 0.01).

Conclusion

COPD patients with PAOD exhibit reduced muscle strength and lower exercise capacity than COPD patients without PAOD.

Nutritional status is the major factor affecting grip strength of African HIV patients before and during antiretroviral treatment

OBJECTIVES

Low grip strength is a marker of frailty and a risk factor for mortality among HIV patients and other populations. We investigated factors associated with grip strength in malnourished HIV patients at referral to ART, and at 12 weeks and 2-3 years after starting ART.

METHODS

The study involved HIV-infected Zambian and Tanzanian participants recruited to the NUSTART trial when malnourished (body mass index <18.5 kg/m² ) and requiring ART. The relationship of grip strength to nutritional, infectious and demographic factors was assessed by multivariable linear regression at referral for ART (n = 1742) and after 12 weeks (n = 778) and 2-3 years of ART (n = 273).

RESULTS

In analyses controlled only for sex, age and height, most nutrition and infection-related variables were associated with grip strength. However, in multivariable analyses, consistent associations were seen for fat-free mass index, mid-upper arm circumference, haemoglobin and systolic blood pressure, and a variable association with fat mass index in men. C-reactive protein and CD4 count had limited independent effects on grip strength, while receiving tuberculosis treatment was associated with weaker grip strength.

CONCLUSIONS

In this population of originally malnourished HIV patients, poor grip strength was more strongly and independently associated with nutritional than with infection and inflammation variables. Programmes to improve health and survival of HIV patients should incorporate nutritional assessment and management and could use grip strength as a functional indicator of improving nutrition.

MicroRNA Dysregulation in Aging and Pathologies of the Skeletal Muscle

Skeletal muscle is one of the biggest organs of the body with important mechanistic and metabolic functions. Muscle homeostasis is controlled by environmental, genetic, and epigenetic factors. Indeed, MiRNAs, small noncoding RNAs robust regulators of gene expression, have and have been shown to regulate muscle homeostasis on several levels: through controlling myogenesis, muscle growth (hypertrophy) and atrophy, as well as interactions of muscle with other tissues. Given the large number of MiRNA target genes and the important role of MiRNAs in most physiological processes and various diseases, MiRNAs may have an enormous potential as therapeutic targets against numerous disorders, including pathologies of muscle. The purpose of this review is to present the current knowledge of the role of MiRNAs in skeletal muscle homeostasis and pathologies and the potential of MiRNAs as therapeutics for skeletal muscle wasting, with particular focus on the age- and disease-related loss of muscle mass and function.

Age-related sarcopenia and its pathophysiological bases

Age-related loss of the skeletal muscle and its function is known as sarcopenia. Definition and diagnostic criteria for sarcopenia have been outlined as consensus statements from several study groups, including usual gait speed, grip strength, and skeletal muscle mass. Whereas underlying mechanisms and pathophysiology of sarcopenia remains to be clarified, recent studies have suggested that chronic inflammatory status as well as lifestyle-related factors in older individuals might contribute to the process and progress of sarcopenia.

Association between phthalate exposure and lower handgrip strength in an elderly population: a repeated-measures study

BACKGROUND

Decreased muscle strength can lead to adverse health outcomes in the elderly. A potential association between phthalate exposure and muscle strength was suggested previously, but has not been investigated directly. We hypothesized that phthalate exposure is associated with lower handgrip strength and that the association is modified by the dietary omega-6 to omega-3 ratio.

METHODS

We analyzed 1,228 participants (≥60 years of age) recruited in Seoul and Asan, Republic of Korea. The study participants were surveyed up to three times between 2012 and 2015. At every survey, we collected urine samples and measured handgrip strength twice for each hand. The associations between urine phthalate metabolite concentrations and handgrip strength were evaluated using linear mixed models. Based on dietary information from 391 individuals who participated in the first survey in Seoul, we evaluated the heterogeneity of the association for those with high and low omega-6 to omega-3 ratios, using 8.81 (the 75th quantile) as a cutoff value.

RESULTS

Log-transformed creatinine-adjusted concentrations of mono-(2-ethyl-5-oxohexyl phthalate (MEOHP), mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP), and mono-n-butyl phthalate (MnBP) were inversely associated with all measured handgrip strengths (β = -0.69 to -0.42, all p-values < 0.05). Associations between phthalate biomarkers and handgrip strength did not differ by sex. When the dietary subgroup was stratified by the omega-6 to omega-3 ratio, the associations were stronger among participants with high ratios.

CONCLUSIONS

We found inverse associations between phthalate biomarkers and handgrip strength in the elderly; this association was modified by the dietary omega-6 to omega-3 ratio.

Associations of Blood Cadmium Levels With Depression and Lower Handgrip Strength in a Community-Dwelling Elderly Population: A Repeated-Measures Panel Study

BACKGROUND

Although biologically plausible, few studies have linked cadmium exposure to depression or muscle strength. Herein, we hypothesized that blood cadmium concentrations are associated with depression and lower handgrip strength in a community-dwelling elderly population.

METHODS

Data from 983 elderly participants who completed up to 3 surveys between 2012 and 2015 were analyzed. At every survey, we assessed depressive status using the Korean version of the Geriatric Depression Scale-Short Form (SGDS-K) and measured handgrip strength and blood cadmium levels (mean, 1.24 μg/L). We evaluated the associations of cadmium with depression using generalized linear mixed models, and handgrip strength using linear mixed models. All models were adjusted for sociodemographic factors, lifestyle factors including active and passive smoking, weight, height, and comorbidity status.

RESULTS

Interquartile-range increase (0.645 μg/L) in blood cadmium levels was associated with depression defined as SGDS-K score ≥8 (odds ratio = 1.27, 95% confidence interval: 1.06, 1.52) and lower handgrip strength (right hand: β = -0.40, 95% confidence interval: -0.75, -0.09; left hand: β = -0.36, 95% confidence interval: -0.69, -0.04). The association between cadmium levels and handgrip strength was robust after further adjustment for depressive status, although it attenuated in size by 14.7%-18.0%.

CONCLUSIONS

After adjusting for potential confounders, blood cadmium concentrations were associated with depression and lower handgrip strength in an elderly population. The participants' depressive status partially mediated the association between cadmium levels and handgrip strength.

Body composition and functional assessment of nutritional status in adults: a narrative review of imaging, impedance, strength and functional techniques

The accurate and valid assessment of body composition is essential for the diagnostic evaluation of nutritional status, identifying relevant outcome measures, and determining the effectiveness of current and future nutritional interventions. Developments in technology and our understanding of the influences of body composition on risk and outcome will provide practitioners with new opportunities to enhance current practice and to lead future improvements in practice. This is the second of a two-part narrative review that aims to critically evaluate body composition methodology in diverse adult populations, with a primary focus on its use in the assessment and monitoring of under-nutrition. Part one focused on anthropometric variables [Madden and Smith (2016) J Hum Nutr Diet 29: 7-25] and part two focuses on the use of imaging techniques, bioelectrical impedance analysis, markers of muscle strength and functional status, with particular reference to developments relevant to practice.

Cross-sectional association between physical strength, obesity, periodontitis and number of teeth in a general population

AIM

Muscle strength declines and gums recede with increasing age across the life course. Possible associations exist between handgrip strength as an indicator of physical fitness and periodontitis and number of teeth.

MATERIAL AND METHODS

Handgrip strength (GS), anthropometric measures, clinical attachment loss, number of teeth, C-reactive protein and glycated haemoglobin were assessed in 2089 participants of the Study of Health in Pomerania (SHIP-2). Linear regression including interaction with age was used to estimate the association between clinical attachment level, number of teeth and GS.

RESULTS

In multiple regression adjusted for age, body mass index (BMI) and waist-to-hip ratio (WHR) each mm of diminished periodontal attachment was associated with reduction in GS by 1.47 kg (95% CI -2.29 to -0.65) and 0.38 kg (-0.89 to 0.14) in men and women respectively. Correspondingly, each additional remaining tooth was significantly associated with higher GS. Using handgrip strength relative to BMI as outcome, these relationships become even more apparent. Indicators of obesity such as BMI and WHR associated with both GS and periodontitis modulate the relationship between GS and periodontitis with a different impact between the sexes.

CONCLUSION

Periodontitis is associated with GS modified mainly by anthropometric measures related to adiposity and inflammation. Putative mechanisms encompass interactions of factors declining with increasing age.

Declines in Strength and Mortality Risk Among Older Mexican Americans: Joint Modeling of Survival and Longitudinal Data

BACKGROUND

Grip strength is a noninvasive method of risk stratification; however, the association between changes in strength and mortality is unknown. The purposes of this study were to examine the association between grip strength and mortality among older Mexican Americans and to determine the ability of changes in strength to predict mortality.

METHODS

Longitudinal data were included from 3,050 participants in the Hispanic Established Population for the Epidemiological Study of the Elderly. Strength was assessed using a hand-held dynamometer and normalized to body mass. Conditional inference tree analyses were used to identify sex- and age-specific weakness thresholds, and the Kaplan-Meier estimator was used to determine survival estimates across various strata. We also evaluated survival with traditional Cox proportional hazard regression for baseline strength, as well as with joint modeling of survival and longitudinal strength change trajectories.

RESULTS

Survival estimates were lower among women who were weak at baseline for only 65- to 74-year-olds (11.93 vs 16.69 years). Survival estimates were also lower among men who were weak at baseline for only ≥75-year-olds (5.80 vs 7.39 years). Lower strength at baseline (per 0.1 decrement) was significantly associated with mortality (hazard ratio [HR]: 1.10; 95% confidence interval [CI]: 1.01-1.19) for women only. There was a strong independent, longitudinal association between strength decline and early mortality, such that each 0.10 decrease in strength, within participants over time, resulted in a HR of 1.12 (95% CI: 1.00-1.25) for women and a HR of 1.15 (95% CI: 1.04-1.28) for men.

CONCLUSIONS

Longitudinal declines in strength are significantly associated with all-cause mortality in older Mexican Americans.

Optimal nutrition in the paediatric ICU

PURPOSE OF REVIEW

This article describes the current best available evidence on optimal nutrition in the paediatric intensive care based on different levels of outcome, which can be divided in surrogate and hard clinical outcome parameters.

RECENT FINDINGS

Undernutrition is associated with increased morbidity and mortality, whereas in specific cohorts of critically ill children, such as those with burn injury, obesity is associated with more complications, longer length of stay, and decreased likelihood of survival. There is a relation with adequacy of delivery of enteral nutrition and the amount of protein on length of hospital stay, neurological status, and mortality. Studies relating organ function, other than skin healing after thermal injury, with the nutritional status are scarce. There is also a scarcity of data concerning long-term follow-up and health economics.

SUMMARY

Until now, there are no randomized controlled trials which have investigated a causal relation between different feeding regimens on the nutritional status and short and long-term outcome. As a result current optimal nutritional strategies are based on small trials with surrogate outcome parameters. Prospective randomized studies are needed with nutritional and/or metabolic interventions to come to an optimal feeding strategy for critically ill children.

Mood, food, and cognition: role of tryptophan and serotonin

PURPOSE OF REVIEW

Food is not only necessary as a metabolic fuel for the body, it becomes more and more evident that there exists an association between food and brain functions like mood and cognition. Tryptophan represents a key element for brain functioning, because of its role as a precursor for production of neurotransmitter serotonin (5-hydroxytryptamine). In clinical conditions, which involve chronic immune system activation or under cytokine therapy, lower tryptophan levels because of high catabolism of tryptophan as indicated by the kynurenine to tryptophan ratio are common and often associate with depressive mood.

RECENT FINDINGS

Studies in the in vitro model of mitogen-stimulated peripheral blood mononuclear cells revealed that several phytocompounds, mainly antioxidants like polyphenols and vitamins, can interfere with inflammatory signaling cascades including tryptophan breakdown. If extrapolated to the in vivo situation, such compounds could increase blood and brain tryptophan availability for serotonin production. Although there is some in vivo evidence for the effect of such compounds, outcomes are hardly predictable and most likely depend on the individual's immunological state.

SUMMARY

Not only a diet rich in tryptophan but also a diet rich in antioxidants can have a positive impact on mood and cognition. This could be of special relevance for individuals who present with low grade inflammation conditions.

The pathogenetic bases of sarcopenia

Aging is accompanied by involuntary loss of skeletal muscle mass, strength and function, called sarcopenia. The mechanisms underlying the development of sarcopenia are not completely understood and most likely multi-factorial, but significant progress has been made over the past few years to identify some of the major contributors. Besides life style-related factors, as diet and physical activity, sarcopenia seems to be also determined by hormonal dysregulation, chronic inflammatory status, ectopic adipose tissue accumulation, neurological and vascular changes associated with aging. The present mini-review focused on the basic factors that primarily impact muscle homeostasis in older subjects. A better understanding of cellular mechanism leading to sarcopenia is required to establish evidence-based intervention in order to prevent onset of symptoms associated with sarcopenia and to extend the time free from disability in older adults.