Marker Of Muscle Mass Research Articles

ADDUCTOR POLLICIS MUSCLE THICKNESS AS A PREDICTOR OF MUSCLE STRENGTH IN HEMODIALYSIS PATIENTS

Muscle mass remains a challenge in the nutritional assessment of hemodialysis (HD) patients. The adductor pollicis muscle thickness (APMt) has emerged as a promising marker of muscle mass in the general population. Thus, we aimed to evaluate whether APMt is able to predict handgrip strength (HGS), a valid muscle mass marker in HD patients. This cross-sectional study evaluated a total of 73 patients (52.3±17 years, 56 months on HD, 48% malnourished by Subjective Global Assessment [SGA] and without residual renal function). The APMt was assessed by a skinfold caliper considering the mean of three measurements. HGS was obtained using a dynamometer. Both methods and other anthropometric parameters were performed in the arm opposite to vascular access and after HD session. Patients were stratified according to gender-specific median HGS (men 24 kg; women 18 kg). APMt values were lower in the group with lower HGS when compared with the group with higher HGS (8,91±4,08 and 11,22±4,64, P=0,02 respectively). A significant correlation was found between AMPt and HGS (r=0,40; P

Relation of Body Mass Index to Urinary Creatinine Excretion Rate in Patients With Coronary Heart Disease

In patients with prevalent coronary heart disease (CHD), studies have found a paradoxical relation in that patients with higher body mass indexes (BMIs) have lower mortality. One possibility is that patients with higher BMIs have greater muscle mass, and higher BMI may be a marker of better overall health status. The aim of this study was to evaluate whether the paradoxical association of BMI with mortality in patients with CHD is attenuated when accounting for urinary creatinine excretion, a marker of muscle mass. The Heart and Soul Study is an observational study of outpatients with stable CHD. Outpatient 24-hour timed urine collections were obtained. Participants were followed up for death for 5.9 ± 1.9 years. Cox proportional-hazards models were used to evaluate the association between gender-specific BMI quintiles and mortality. There were 886 participants in the study population. Participants in higher quintiles of BMI were younger, were more likely to have diabetes mellitus and hypertension, and had higher urinary creatinine excretion rate. Compared to the lowest BMI quintile, subjects in higher BMI quintiles were less likely to die during follow-up. Adjustment for major demographic variables, traditional cardiovascular risk factors, and kidney function did not attenuate the relation. Additional adjustment for urinary creatinine excretion rate did not materially change the association between BMI and all-cause mortality. In conclusion, low muscle mass and low BMI are each associated with greater all-cause mortality, but low muscle mass does not appear to explain why CHD patients with low BMIs have worse prognosis.

Abdominal fat mass contributes to the systemic inflammation in chronic obstructive pulmonary disease

BACK GROUND & AIMS: Altered body composition in chronic obstructive pulmonary disease (COPD) is often reflected by muscle wasting, while only few studies have focused on abdominal fat mass. The contribution of abdominal fat mass to the systemic inflammation often present in COPD has not been examined yet. The aim of the present study was to investigate if abdominal fat mass contributes to the systemic inflammation in patients with moderate to severe COPD. Muscle wasting (fat free mass index <17.1 kg/m(2) for men and 14.6 kg/m(2) for women) and abdominal fat mass (android/gynoid %fat mass >1.0 for men and >0.8 for women) were assessed by dual-energy X-ray absorptiometry in 295 patients with moderate to severe COPD (175 men). Plasma C-reactive protein (CRP) concentration was analysed by high sensitive (HS)-ELISA. Diffusion capacity was higher in patients with abdominal obesity. In addition, fat mass index was a significant determinant for plasma CRP concentration. In a subgroup of patients with CRP<5 mg/l (n=168), CRP was positively associated with abdominal fat mass. In addition, a significant proportion of abdominal obese patients had muscle wasting, and CRP levels were higher in these patients compared to the patients without abdominal obesity. Abdominal fat mass contributes to the systemic inflammation in COPD. This study provides further evidence for systemic phenotyping of patients with COPD incorporating besides markers of muscle mass also markers of abdominal obesity.

Urinary creatinine excretion rate and mortality in persons with coronary artery disease: the Heart and Soul Study.

In persons with coronary artery disease, low body mass index is associated with greater mortality; however, it is uncertain whether low muscle mass is a risk factor for mortality in this setting. In this study, 903 individuals with coronary artery disease provided 24-hour urine collections. We measured urine creatinine and volume and calculated creatinine excretion rate, a marker of muscle mass. Cox proportional-hazards models evaluated the association of creatinine excretion rate with mortality risk. Over a median follow-up of 6.0 years, 232 participants (26%) died. Compared with the highest sex-specific creatinine excretion rate tertile, the lowest tertile (<1068 mg/d in men, <766 mg/d in women) was associated with >2-fold risk of mortality (hazard ratio, 2.30; 95% confidence interval, 1.51 to 3.51) in models adjusted for age, sex, race, cystatin C-based estimated glomerular filtration rate, body mass index, traditional cardiovascular disease risk factors, and C-reactive protein levels. The association was essentially unaltered with further adjustment for physical fitness, left ventricular mass, left ventricular ejection fraction, or fasting insulin and glucose levels. Lower creatinine excretion rate is strongly associated with mortality in outpatients with coronary artery disease, independently of conventional measures of body composition, kidney function, and traditional coronary artery disease risk factors. Future studies should determine whether low creatinine excretion rate may be a modifiable risk factor for mortality among persons with coronary artery disease, potentially through resistive exercise training or nutrition interventions.

Reliability of results and interpretation of measures of 3-methylhistidine in muscle interstitium as marker of muscle proteolysis

TO THE EDITOR: We were interested in the contribution by Tesch and colleagues to the evidence base concerning the events subsequent to acute immobilization in human muscle. Tesch and colleagues (14) used a microdialysis technique applied to human muscle in an attempt to measure an index of myofibrillar proteolysis 72 h after immobilization using the unilateral leg suspension technique. The authors discuss their results as though they had good evidence that the technique they used produces results that are sufficiently firm to be the basis of conjecture about mechanisms of protein balance in muscle after immobilization. We demur and propose that they are on very shaky ground. First, we wonder about the size of the effect reported. The authors claim it to be 44%, but calculation of the change shows it to be actually 29% with the SEs sufficiently large that they almost span the difference; SDs must overlap. Significance at the 5% level can only barely have been reached. Are the authors convinced that they have not ignored a type I error? The authors (14) begin their explanation of the advantages of the dialysis technique using 3-methylhistidine (3MeHis) by describing the gold standard method, i.e., the stable isotopelabeled amino acid tracer dilution method, as cumbersome and possibly unjustified in study of otherwise healthy subjects. We find this notion strange since Ferrando and colleagues (6, 12) have used the technique in many studies of how immobilization affects muscle protein turnover subsequent to disuse. We have also used the techniques in a wide variety of studies of proteolysis in healthy and infirm subjects (1, 2, 10, 11, 15) with no problems and, we would propose, producing results with a greater degree of certainty and biological appropriateness than those obtained by the 3MeHis dialysis technique.

Myoglobin plasma level related to muscle mass and fiber composition – a clinical marker of muscle wasting?

Progressive muscle wasting is a central feature of cancer-related cachexia and has been recognized as a determinant of poor prognosis and quality of life. However, until now, no easily assessable clinical marker exists that allows to predict or to track muscle wasting. The present study evaluated the potential of myoglobin (MG) plasma levels to indicate wasting of large locomotor muscles and, moreover, to reflect the loss of MG-rich fiber types, which are most relevant for daily performance. In 17 cancer-cachectic patients (weight loss 22%) and 27 age- and gender-matched healthy controls, we determined plasma levels of MG and creatine kinase (CK), maximal quadriceps muscle cross-sectional area (CSA) by magnetic resonance imaging, muscle morphology and fiber composition in biopsies from the vastus lateralis muscle, body cell mass (BCM) by impedance technique as well as maximal oxygen uptake (VO(2)max). In cachectic patients, plasma MG, muscle CSA, BCM, and VO(2)max were 30-35% below control levels. MG showed a significant positive correlation to total muscle CSA (r = 0.65, p < 0.001) and to the CSA fraction formed by type 1 and 2a fibers (r = 0.80, p < 0.001). However, when adjusted for body height and age by multiple regression, MG yielded a largely improved prediction of total CSA (multiple r = 0.83, p < 0.001) and of fiber type 1 and 2a CSA (multiple r = 0.89, p < 0.001). The correlations between CK and these muscle parameters were weaker, and elevated CK values were observed in 20% of control subjects despite a prior abstinence from exercise for 5 days. In conclusion, plasma MG, when adjusted for anthropometric parameters unaffected by weight, may be considered as a novel marker of muscle mass (CSA) indicating best the mass of MG-rich type 1 and 2a fibers as well as VO(2)max as an important functional readout. CK plasma levels appear to be less reliable because prolonged increases are observed in even subclinical myopathies or after exercise. Notably, cancer-related muscle wasting was not associated with increases in plasma MG or CK in this study.

Normalization of Protein Intake by Body Weight and the Associations of Protein Intake With Nutritional Status and Survival

To examine the associations of total protein intake (TPI) and dietary protein intake (DPI) with baseline nutrition and subsequent mortality. Retrospective analysis of incident dialysis patients. National cohort from The United States Renal Data System data. Incident dialysis patients (n = 5,059) with blood urea nitrogen (BUN) and urea clearances reported on form 2728. TPI was calculated from BUN and urea clearance. DPI was defined as TPI divided by weight. Urinary creatinine (UCr) calculated from creatinine clearance and serum creatinine was used as a marker of muscle mass. The associations of TPI and DPI with each of serum albumin < or = 3.3 g/dL (50th percentile), UCr < or = 0.56 g/d (25th percentile), body mass index < 18.5, and death were examined. Compared with patients in the highest quartile of TPI (> 60.2 g/d), those in the lowest quartile (< or = 32.4 g/d) had 1.89-fold higher odds (P < .001) of low serum albumin, 10.22-fold higher odds (P < .001) of low UCr, and 3.83-fold higher odds (P < .001) of low body mass index in multivariable logistic regression models, and an 18% increase (P < .001) in hazard of death. Compared with patients with DPI > 1.2 g/kg/d, those with DPI < 0.8 g/kg/d had nonsignificantly higher odds of low serum albumin, 2.38-fold higher odds (P < .001) of low UCr, and 0.44-fold lower odds (P < .001) of low body mass index, and a 15% (P = .04) decrease in hazard of death. Higher TPI is associated with better nutrition at baseline and subsequent survival. Normalization of TPI by body weight provides contradictory information on nutritional status as well as survival.

Analysis of muscle strength and bone structure in children with renal disease.

Bone structure and muscular strength of 30 children with renal disease were investigated by peripheral computed tomography and grip strength. Sixteen children suffered from nephrotic syndrome (NS) and had previously been treated with corticosteroids. Fourteen children suffered from chronic renal failure (CRF) ranging from mild renal failure to end-stage renal disease. Six children had received kidney transplants and corticosteroids for immunosuppression. There was a significant decrease in grip strength of children with NS (SD -0.91+/-1.5; P=0.042) and children with CRF (SD -1.38+/-1.4; P<0.001) compared with normal children. Furthermore, there was a significant correlation between cortical area and grip strength in all children with renal disease (r=0.92; P<0.0001). Trabecular bone mineral density did not correlate well with grip strength. These findings resemble results found in healthy children. Trabecular bone mineral density was significantly elevated in children with CRF compared with normal children (SD 1.14+/-1.4; P=0.008). Grip strength as a marker of muscle mass and cortical area as a marker of bone strength correlate well in children with renal disease, similar to the correlation in healthy children. Grip strength is significantly lower in children with NS and CRF compared with normal children. These data suggest that muscular impairment could be involved in renal osteopathy.