Influence of body composition, muscle strength, diet and physical activity on total body and forearm bone mass in Chinese adolescent girls

The aim of the present study was to determine association between body composition, muscle strength, diet and physical exercise with bone mineral content (BMC) and bone area (BA) in 283 Chinese adolescent girls aged 15 years in Beijing, China. Body composition, pubertal stage, physical activity and dietary intakes were assessed using standard validated protocols. Total body and forearm bone, lean body mass (LBM) and fat body mass (FBM) were determined by dual X-ray absorptiometry. Multivariate linear regression analyses were carried out to examine the predictors of BMC and BA, after controlling for potential confounders. The subjects had a mean age of 15.0 (sd 0.9) years and 99.6 % of them had reached menarche. Multivariate analyses showed that LBM, FBM, handgrip muscle strength and milk intake were significant independent determinants of BMC and BA of the total body and/or forearm sites. LBM was found to be a stronger independent determinant than FBM of BMC and BA, whereas handgrip muscle strength was only found as significant determinant of BMC and BA at the forearm sites than in total body BMC and BA. Further, total physical activity level had a significant positive association with handgrip and LBM. This suggested that greater muscle strength and higher LBM may reflect higher levels of physical activity. Therefore, continuous healthy lifestyle practices such as adequate intake of milk and continuous participation in physical activity should be encouraged throughout adolescence to optimise bone growth during this period.     

Associations of Sarcopenia and Sarcopenic Obesity With Metabolic Syndrome Considering Both Muscle Mass and Muscle Strength

Objectives:

We investigated the associations of sarcopenia-defined both in terms of muscle mass and muscle strength-and sarcopenic obesity with metabolic syndrome.

Methods:

Secondary data pertaining to 309 subjects (85 men and 224 women) were collected from participants in exercise programs at a health center in a suburban area. Muscle mass was measured using bioelectrical impedance analysis, and muscle strength was measured via handgrip strength. Sarcopenia based on muscle mass alone was defined as a weight-adjusted skeletal muscle mass index more than two standard deviations below the mean of a sex-specific young reference group (class II sarcopenia). Two cut-off values for low handgrip strength were used: the first criteria were <26 kg for men and <18 kg for women, and the second criteria were the lowest quintile of handgrip strength among the study subjects. Sarcopenic obesity was defined as the combination of class II sarcopenia and being in the two highest quintiles of total body fat percentage among the subjects. The associations of sarcopenia and sarcopenic obesity with metabolic syndrome were evaluated using logistic regression models.

Results:

The age-adjusted risk ratios (RRs) of metabolic syndrome being compared in people with or without sarcopenia defined in terms of muscle mass were 1.25 (95% confidence interval [CI], 1.06 to 1.47, p=0.008) in men and 1.12 (95% CI, 1.06 to 1.19, p<0.001) in women, which were found to be statistically significant relationships. The RRs of metabolic syndrome being compared in people with or without sarcopenic obesity were 1.31 in men (95% CI, 1.10 to 1.56, p=0.003) and 1.17 in women (95% CI, 1.10 to 1.25, p<0.001), which were likewise found to be statistically significant relationships.

Conclusions:

The associations of sarcopenia defined in terms of muscle mass and sarcopenic obesity with metabolic syndrome were statistically significant in both men and women. Therefore, sarcopenia and sarcopenic obesity must be considered as part of the community-based management of non-communicable diseases.     

SGA and measures for muscle mass and strength in surgical Vietnamese patients

OBJECTIVE: This study compared the outcome of the Subjective Global Assessment (SGA) in preoperative surgical patients with objective measurements of muscle mass and strength and with biochemical data. A secondary aim was to test the influence of inflammatory activity on muscle strength. METHODS: Two hundred seventy-four consecutive patients who were admitted for elective major abdominal surgery were assessed using the SGA, anthropometry, muscle strength, and laboratory measurements (hemoglobin, protein, albumin, C-reactive protein, and lymphocytes). Normal values for midarm muscle circumference (MAMC) and handgrip strength were obtained in a healthy control group. For all other variables, normal values available for the Vietnamese population were used. RESULTS: Of 274 patients (151 men, 123 women) assessed, 61 (22.3%) were classified as SGA class A (well nourished), 97 patients (35.4%) as class B (moderately malnourished), and 116 patients (42.3%) as class C (severely malnourished). There were significant differences in age, body weight, percentage of weight loss, triceps skinfold thickness, MAMC, and serum albumin across the three SGA classes. Almost all patients rated class A had normal MAMC and handgrip strength. However, a large proportion of patients rated as B or C also had normal MAMC and handgrip strength (38% of men, 50% of women). Handgrip strength per square meter correlated with serum albumin (r = 0.278, P < 0.001) and this correlation persisted when handgrip strength was controlled for MAMC (r = 0.296, P < 0.001 in men; r = 0.237, P < 0.01 in women). CONCLUSION: The SGA correctly identifies patients with normal muscle mass and strength but a substantial number of patients rated SGA B or C have normal muscle mass and strength. Muscle strength is not only positively associated with muscle mass but also negatively with inflammatory activity.     

Prevalence of sarcopenia in the French senior population

Introduction A muscle mass normalized for height² (MMI) or for body weight (SMI) below 2SD under the mean for a young population defines sarcopenia. This study aimed at setting the cutoffs and the prevalence of sarcopenia in the French elderly population. Another objective was to compare the results obtained with SMI and MMI.Methods: Muscle mass was assessed by bioelectrical impedance analysis in 782 healthy adults (<40 years) to determine skeletal mass index (SMI, muscle mass*100/weight) and muscle mass index (MMI, muscle mass/height²). Prevalence was estimated in 888 middle aged (40–59 years) and 218 seniors (60–78 years). All were healthy people.Results: For women mean-2SD were 6.2 kg/m² (MMI) and 26.6% (SMI); for men limits were 8.6 kg/m² (MMI) and 34.4% (SMI). In middle aged persons a small number of them were identified as sarcopenic. In healthy seniors, 2.8% of women and 3.6% of men were sarcopenic (MMI). The prevalence was 23.6% in women and 12.5% in men with SMI. MMI and SMI identified different sarcopenic populations, leaner subjects for MMI while fatter subjects for SMI.Conclusion: Cutoff values for the French population were defined. Prevalence of sarcopenia was different from that in the US population.     

Anthropometric measurements in the elderly of Havana, Cuba: age and sex differences

OBJECTIVE: We present selected anthropometric data, specific for sex and age group, from a representative sample of elderly subjects living in Havana, Cuba. METHODS: This was a cross-sectional, population-based household survey. A total of 1905 subjects (1197 women and 708 men, > or = 60 y of age) were examined between 1999 and 2000 as selected by probabilistic sampling. Data were presented as means and percentiles for body mass; height or stature; body mass index; waist, arm, and calf circumferences; triceps skinfold thickness; and arm muscle circumference; and differences were described according to age (all variables) and sex (body mass index). RESULTS: All anthropometric variables showed a decrease in average values with aging in men and women. The age of 70 y appeared to be the decisive moment for the main anthropometric differences observed. The values in the female group were higher than those in the male group for body mass index and triceps skinfold thickness. An important segment of the population studied had a body mass index lower than normal values. Reductions in subcutaneous fat (indicated by triceps skinfold thickness) and muscle mass (verified by arm, arm muscle, and calf circumferences) with advancing age appeared to be greater among women than among men. CONCLUSION: The present study provides information that can be used for anthropometric evaluation of elderly people in Havana and other urban areas in Cuba. The observations suggest that there is loss of muscle mass and redistribution and reduction of fat mass with age (that is more severe in women).     

Elderly cohort study subjects unable to return for follow-up have lower bone mass than those who can return

Longitudinal studies of osteoporosis in older persons may underestimate bone loss because of a lack of follow-up measurements on subjects too frail to return. The authors addressed this possible bias as part of the population-based Framingham Study; in 1996-1997, they used quantitative ultrasound to assess the bone status of elderly subjects regardless of their ability to return to the clinic. Broadband ultrasound attenuation (BUA) and speed of sound of the calcaneus (heel) were measured in 433 subjects at the Framingham, Massachusetts, clinic and in 167 subjects at their homes or nursing homes. All ultrasound parameters were measured with intramachine coefficients of variation of <6.0%. The mean BUA for those subjects evaluated at the clinic was higher than for those measured at home (9.2% higher for men, p = 0.081; 8.6% higher for women, p = 0.034). After adjustment for age and weight, the differences in BUA were no longer significant. Among the elderly subjects participating in this longitudinal cohort study, those who were unable to return for follow-up were older, weighed less, and had a lower BUA than those who did return, suggesting that longitudinal studies of changes in bone mass with aging may underestimate the true population values.     

Anthropometric measurements in the elderly population of Santiago, Chile

OBJECTIVE: There are few studies on anthropometry and nutritional status in large and representative samples of elderly populations in Chile and South America. We describe age and sex differences in weight, height, body mass index, knee height, waist circumference, midarm circumference, triceps skinfold thickness, arm muscle area, and calf circumference in Chilean elderly subjects. METHODS: This was a population-based, cross-sectional study. A total of 1220 elderly persons (819 women and 411 men; age range, 60-99 y) were recruited in the city of Santiago (Chile) through a probabilistic sampling procedure carried out from October to December 1999. RESULTS: Men were significantly heavier and taller than women in all age groups, whereas body mass index values were significantly higher in women than in men. All anthropometric variables showed a decrease in average values with aging in men and women. The apparent negative slopes for the decline in average values of body weight with aging was of greater magnitude in women than in men (-0.42 kg/y and -0.54 kg/y in male and female subjects, respectively). However, significant age x sex interaction was detected only for triceps skinfold thickness. In women, quadratic terms for age provided a significantly better fit than did the simple linear model for the association between age and weight, body mass index, waist circumference, triceps skinfold thickness, calf circumference, or midarm circumference. CONCLUSION: These observations indicated that body weight changes associated with aging might be more severe in Chilean women than in men, probably determining a differential pattern of lean and fat mass loss.     

A comparison of mortality rates in three prospective studies from Copenhagen with mortality rates in the central part of the city, and the entire country

Valid generalizations of results from population-based epidemiological surveys requires knowledge about how representative the sample is. The Copenhagen Center for Prospective Population Studies have assessed mortality on the basis of pooled data from three research programmes in the region of Copenhagen. In two of the studies, subjects were randomly selected, using the Danish Central Population Registry, within certain age groups and area-restricted sectors of the Greater Copenhagen. In the third study, men employed in 14 companies participated. Participation rates were between 78% and 87% in the three programmes. Standardized mortality rates (SMR) were calculated in relation to mortality rates in the municipality of Copenhagen and in the whole country in three age groups and the two genders. SMR values in the whole sample including non-participants were similar to rates for Copenhagen in the Copenhagen City Heart Study, whereas mortality rates in the Glostrup Population Studies were similar to rates for the whole country. The mortality rates among participants were lower than in the whole sample, and differences existed in relation to region and selection criteria of the cohorts. The Copenhagen Male Study, where only employed men were included, showed the lowest mortality rates, and higher rates were found in the study from the central part of the City (the Copenhagen City Heart Study) compared to the study from the suburbs (the Glostrup Population Studies). The difference between mortality rates in the cohorts and in Copenhagen City decreased with increasing age. The SMR converged towards 1.00 with increasing observation time. In conlusion, high participation rates were found in all three studies, resulting in SMR values for participants only slightly lower than in the source population in the two randomly selected samples, but 30% lower values in the sample of employed men. As mortality rates in the total samples including non-participants were markedly higher than among the participants, generalizations of results for participants to the whole population should be made with caution, especially during the first years of observation.     

Longitudinal changes in forearm bone mineral density in women and men aged 45-84 years: the Tromso Study, a population-based study

The aim of this study was to describe changes in bone mineral density in Norwegian women and men aged 45-84 years in a population-based, longitudinal study. Bone mineral density (g/cm2) was measured at distal and ultradistal forearm sites with single x-ray absorptiometric devices in 3,169 women and 2,197 men at baseline in 1994-1995 and at follow-up in 2001 (standard deviation, 0.4 years). The mean annual bone loss was -0.5% and -0.4% in men and -0.9% and -0.8% in women not using hormone replacement therapy at the distal and ultradistal sites, respectively. In men, age was a negative predictor of bone mineral density change at both sites. Women not using hormone replacement therapy had the highest bone loss at the ultradistal site 1-5 years after menopause. The correlation between the two measurements was high: r = 0.93 and r = 0.90 in women and r = 0.96 and r = 0.93 in men for the distal and ultradistal sites, respectively. More than 70% kept their quartile positions, indicating a high degree of tracking of bone mineral density measurements. Although the study population live above the polar circle, the rate of bone loss was not higher at the distal and ultradistal forearm sites compared with that of other cohorts.     

A radiographic method of quantifying protein-calorie undernutrition.

Estimation of midarm adipose tissue and muscle by the anthropometric technique is based on the idealized assumption that the arm and its muscle compartments are circular, and that fat is distributed evenly around the arm. We examined the validity of these assumptions by computerized axial tomography of the midarm in 21 subjects ranging from 65 to 255% of ideal body weight. Computerized axial tomography identified three errors inherent in the anthropometric method: 1) The arm and its muscle compartment were rarely circular, but resembled instead an ellipse and "cloverleaf", respectively; 2) fat was distributed asymmetrically around the arm, and furthermore when triceps skinfold was less than 5 mm, no fat was radiographically detectable, and 3) muscle are calculated by the anthropometric method includes bone area. Since bone area was not influenced by nutritional status, anthropometric "muscle area" underestimated the degree of muscle atrophy in undernutrition. Despite these limitations, in subjects 60 to 120% of ideal body weight anthropometric estimates of midarm muscle area (MAMA) and fat area did not differ greatly from the radiographic values. Anthropometric MAMA was consistently greater than the radiographic value by 15 to 25%, while midarm fat area agreed within +/- 10%. The error in the anthropometric MAMA could be nearly eliminated by two types of correction: expressing MAMA as a percentage of normal, and correcting for bone content by subtracting midarm bone area (6.3 and 4.7 cm2 for men and women). In subjects greater than 150% ideal body weight, however, anthropometric estimates of MAMA and midarm fat area differed from the radiographic values by greater than 50% even after the above two types of correction. Midarm computerized axial tomography scan provides an accurate alternative to the anthropometric method for estimating midarm muscle and fat in these obese individuals.     

Hormonal and lifestyle determinants of appendicular skeletal muscle mass in men: the MINOS study

BACKGROUND: Aging-related sarcopenia is characterized by a loss of muscle mass and strength and increased fatigability. However, studies of its determinants in elderly men are scarce. OBJECTIVE: We investigated risk factors for sarcopenia in a large cohort of men. DESIGN: We analyzed 845 men aged 45-85 y who belonged to the MINOS cohort. Lifestyle factors (physical activity, tobacco smoking, alcohol intake, caffeine intake) were evaluated by using a standardized questionnaire. Appendicular skeletal muscle mass (ASM) was estimated by using dual-energy X-ray absorptiometry. The relative appendicular skeletal muscle mass index (RASM) was calculated as ASM/body height(2.3). Apparent free testosterone concentration (AFTC) and free testosterone index (FTI) were calculated on the basis of concentrations of total testosterone and sex hormone-binding globulin. RESULTS: RASM decreased with age (r = -0.29, P < 0.0001). Current smokers had lower RASM than did subjects who never smoked (-3.2%; P < 0.003). RASM increased with the intensity of physical activity at work (P for trend < 0.001). Men who participated in regular exercise during leisure time had 2.2% higher RASM than did those who did not (P < 0.03). Men whose values for AFTC, FTI, or 25-hydroxycholecalciferol [25(OH)D] were >2 SDs below the mean for young men had significantly lower RASM than did men with higher values. Men with sarcopenia, defined as the lowest quartile of RASM in the studied cohort (<6.32 kg/m(2.3)), were significantly older than men with normal RASM, weighed significantly less, smoked more, and spent significantly less time on leisure-time activities. Sarcopenic men also had lower values for testosterone, AFTC, FTI, and 25(OH)D. CONCLUSION: In elderly men, low physical activity, tobacco smoking, thinness, low testosterone (AFTC and FTI), and decreased 25(OH)D concentrations are risk factors for sarcopenia.     

Relationships between structural and functional measures of nutritional status in a normally nourished population

BACKGROUND AND AIMS: Both anthropometric and functional measurements have been used in nutritional assessment and monitoring. Hand dynamometry is a predictor of surgical outcome and peak expiratory flow rate has been used as an index of respiratory muscle function. This study aims to measure in normal subjects the relationship between anthropometric measurements, voluntary muscle strength by hand grip dynamometry and respiratory muscle function by peak expiratory flow rate. METHODS: Ninety-eight subjects (46 male, 52 female) with a mean age of 45.9 years were studied. Hand grip strength was measured in the dominant and non-dominant hands with a portable strain-gauge dynamometer. Peak expiratory flow rate was measured using a mini-Wright peak flow meter. Three readings were taken, each 1 min apart, and the average recorded. Midarm muscle circumference (MAMC) was derived from triceps skin fold thickness and midarm circumference (MAC) using standard anthropometric techniques. Statistical relationships were measured with Pearson's coefficient of correlation. RESULTS: In both sexes there was significant correlation between hand grip strength in the dominant and non-dominant hands and peak expiratory flow rate (P<0.001). In men, there was a positive correlation between MAMC, hand grip strength (P<0.001) and peak expiratory flow rate (P<0.001). In women muscle function correlated with height (P<0.001) but not MAMC (P>0.05). CONCLUSIONS: In normal subjects bedside tests of skeletal and respiratory muscle function correlated with each other in both sexes, and with muscle mass in men but not in women.     

Effects of resistive training on strength gains in older adults

This study was designed to evaluate the effects of a moderate intensity, 16-week resistive strength training program on the rate and pattern of strength changes in trunk, upper, and lower extremity muscle groups. This study was also designed to determine the importance of muscle mass on strength gains during a training intervention with older adults. A repeated measures experimental design was employed with 43 experimental (ES) and 42 comparison subjects (CS). The active older sample had a relatively high level of strength for their age (72.1 yr) and had no contraindications for strength training. The ES trained five upper, three trunk, and three lower extremity muscle groups. Both ES and CS received pre- and post-testing assessments for muscle strength, muscle morphology, body composition, flexibility, and balance. The ES also received intermittent testing for one repetition maximum (1RM). ANOVA and Scheffé HSD tests were used to evaluate the data. The ES experienced significant strength gains (over 41% for each body segment) following the intervention. The rate of gain in this study was less than but the absolute strength gain was reasonably similar to values reported by studies in the literature [1,2]. There was no change in muscle mass (p>.05) following training. These results suggests that stronger active older adults have a muscle mass sufficient for greater strength and that training enables them to use available muscle mass more effectively. These results further suggest that muscle hypertrophy may be possible following strength training but it is not always necessary for strength improvement in older adults.     

男性吸烟与骨密度及骨生化指标关系

目的探讨男性吸烟与骨密度及骨生化指标关系。方法用DXA仪测定腰椎及髋部骨密（BMD），用ELISA测定389例20～80岁健康男性血清骨特异性碱性磷酸酶（sBAP）和I型胶原氨基末端肽（sNTX）。结果（1）各部位BMD均在20岁～年龄组最高，30岁之后随年龄增加而缓慢下降；40—60岁各年龄组之间的BMD差异无统计学意义。（2）除腰椎侧位BMD外，吸烟组其它各部位BMD显著低于非吸烟组；吸烟组的BAP显著高于非吸烟组，2组之间的sNTX差异无统计学意义。（3）校正年龄与BMI后，烟龄与腰椎正位，髋部总体，股骨颈及ward＇s区BMD均呈负相关（P〈0．05）。每日吸烟量与腰椎正位及Ward＇s区BMD呈负相关（P〈0．05）。结论男性随年龄增长骨量丢失。男性吸烟者骨生化指标与骨转换水平增高，骨量丢失加速。吸烟等生活方式增高骨转换水平，影响骨转换的增龄性变化并加速骨量的丢失。吸烟是骨质疏松的一个危险因素。预防骨质疏松症（OP）应提倡戒烟。     

Body mass index: comparing mean values and prevalence rates from telephone and examination surveys

BACKGROUND: Cost effective means of assessing the levels of risk factors in the population have to be defined in order to monitor these factors over time and across populations. This study is aimed at analyzing the difference in population estimates of the mean levels of body mass index (BMI) and the prevalences of overweight, between health examination survey and telephone survey. METHODS: The study compares the results of two health surveys, one by telephone (N=820) and the other by physical examination (N=1318). The two surveys, based on independent random samples of the population, were carried out over the same period (1992-1993) in the same population (canton of Vaud, Switzerland). RESULTS: Overall participation rates were 67% and 53% for the health interview survey (HIS) and the health examination survey (HES) respectively. In the HIS, the reporting rate was over 98% for weight and height values. Self-reported weight was on average lower than measured weight, by 2.2 kg in men and 3.5 kg in women, while self-reported height was on average greater than measured height, by 1.2 cm in men and 1.9 cm in women. As a result, in comparison to HES, HIS led to substantially lower mean levels of BMI, and to a reduction of the prevalence rates of obesity (BMI>30 kg/m(2)) by more than a half. These differences are larger for women than for men. CONCLUSION: The two surveys were based on different sampling procedures. However, this difference in design is unlikely to explain the systematic bias observed between self-reported and measured values for height and weight. This bias entails the overall validity of BMI assessment from telephone surveys.     

Grip strength, body composition, and mortality

BACKGROUND: Several studies in older people have shown that grip strength predicts all-cause mortality. The mechanisms are unclear. Muscle strength declines with age, accompanied by a loss of muscle mass and an increase in fat, but the role that body composition plays in the association between grip strength and mortality has been little explored. We investigated the relation between grip strength, body composition, and cause-specific and total mortality in 800 men and women aged 65 and over. METHODS: During 197374 the UK Department of Health and Social Security surveyed random samples of men and women aged 65 and over living in eight areas of Britain to assess the nutritional state of the elderly population. The survey included a clinical examination by a geriatrician who assessed grip strength and anthropometry. We used Cox proportional hazards models to examine mortality over 24 years of follow-up. RESULTS: Poorer grip strength was associated with increased mortality from all-causes, from cardiovascular disease, and from cancer in men, though not in women. After adjustment for potential confounding factors, including arm muscle area and BMI, the relative risk of death in men was 0.81 (95% CI 0.700.95) from all-causes, 0.73 (95% CI 0.600.89) from cardiovascular disease, and 0.81 (95% CI 0.660.98) from cancer per SD increase in grip strength. These associations remained statistically significant after further adjustment for fat-free mass or % body fat. CONCLUSION: Grip strength is a long-term predictor of mortality from all-causes, cardiovascular disease, and cancer in men. Muscle size and other indicators of body composition did not explain these associations.     

Sarcopenic obesity and metabolic syndrome in adult Caucasian subjects

Objectives

Recently metabolic aspects linked to sarcopenic obesity (SO) were investigated. Extant studies involved especially older people from Asian or White-mixed American cohorts. The aims of our study were: to explore the prevalence of sarcopenia in Caucasian adult obese subjects using two different indices of sarcopenia, and to investigate the relationship among SO, metabolic syndrome (MS), inflammation, and serum albumin concentrations.

Design

Cross- sectional study.

Subjects/methods

The study was performed from 2011 to 2014 in a hospitalized care setting. Inclusion criteria were: age>18 and <65 years, BMI=30 Kg/m². Fat mass (FM) and fat-free mass (FFM) were assessed by DXA. Appendicular skeletal muscle mass (ASMM) was calculated. Sarcopenia was defined as ASMM/height² or ASMM/weight <2SD than the sex-specific mean of a young population. The cutoffs were ASMM/h2<6.54 Kg/m² for men and 4.82 Kg/m² for women, and ASMM/weight<0.2827 for men and 0.2347 for women. ISI-Matsuda was calculated. MS was diagnosed (NCEP-ATPIII).

Results

727 subjects (age: 45.72±13.56 years, BMI: 37.74±5.82 kg/m²) were enrolled. The prevalence of SO was 1.0% or 34.8% in men and 0.6% or 50.1% in women, using ASMM/height2 ratio or ASMM/weight. Subjects with SO based on ASMM/height2 were scarce, only data relying on ASMM/weight were considered. Subjects with SO had higher BMI, waist circumference, FM, and lower FFM and ASMM than nonsarcopenic obese individuals (all p<0.05). ISI-Matsuda was lower and hs-CRP levels were higher in subjects with SO (all p<0.05). MS was more prevalent in subjects with SO than nonsarcopenic obese subjects (47.6% vs 34.3%, p<0.001). ASMM/weight was decreased in subjects with MS (0.2522±0.0410 vs 0.2423±0.0352, p=0.001).

Conclusion

SO is associated with MS and low- grade inflammation in adult Caucasian subjects. Metabolic profile evaluation should be recommended in subjects with SO.

     

Age-Related Variations of Muscle Mass,Strength, and Physical Performance in Community-Dwellers: Results From the Milan EXPO Survey

Objectives

Declining muscle mass and function are hallmarks of the aging process. The preservation of muscle trophism may protect against various negative health outcomes. Age- and sex-specific curves of muscle mass, strength, and function, using data from a large sample of community-dwelling people, are necessary.

Elevated homocysteine levels are associated with low muscle strength and functional limitations in older persons

Objective

The current study aimed to examine homocysteine in relation to different aspects of physical functioning.

Design, setting and participants

Cross-sectional and longitudinal data (3-years follow-up) from the Longitudinal Aging Study Amsterdam (LASA) were used. The study was performed in persons aged ≥ 65 years (N= 1301 after imputation).

Measurements

Different measures of physical functioning, including muscle mass, grip strength, functional limitations, and falling were regarded as outcomes. Gender and serum creatinine level were investigated as effect modifiers.

Results

Results were stratified by gender. In men, higher homocysteine levels were associated with lower grip strength (Quartile 4: regression coefficient (B)= ?3.07 (?4.91; ?1.22)), and more functional limitations at baseline (Quartile 4: B= 1.15 (0.16–2.14)). In women, higher homocysteine levels were associated with more functional limitations after 3 years (Quartile 4: B= 1.19 (0.25; 2.13)). Higher homocysteine levels were not associated with low muscle mass or falling.

Conclusions

These data suggest an inverse association of homocysteine levels with functional limitations in older men and women, and with muscle strength in older men.     

中国10个地区成年人骨骼肌质量和手握力的描述性分析

目的 描述中国10个地区成年人骨骼肌质量和手握力的地区和人群分布特征。方法 对来自中国慢性病前瞻性研究项目第2次重复调查的24 533名研究对象进行分析。采用生物电阻抗分析法测量四肢和躯干的肌肉质量,通过Jamar手持握力计测量手握力来衡量肌肉力量水平,并根据亚洲肌少症工作组（AWGS）推荐的标准判断人群低肌肉质量和力量的比例。分地区和人群特征,报告肌肉质量和手握力的均值及标准误,以及低肌肉质量和力量的百分比。结果 男性的四肢和全身肌肉质量分别为（22.0±0.02）kg和（49.7±0.05）kg,高于女性的（15.9±0.02）kg和（37.2±0.04）kg;男性手握力为（32.6±0.06）kg,高于女性的（19.9±0.05）kg。绝对肌肉质量和手握力均呈现北方高于南方、城市高于农村的地区差异（P<0.001）。而身高和体重调整的肌肉质量的地区差异规律相反。随着年龄的增加,肌肉质量各项指标和手握力均呈线性下降趋势（线性趋势P<0.001）,且手握力下降幅度更大。进一步按照AWGS判断,低肌肉质量和力量的比例随年龄增加而不断上升,≥ 80岁的老年男性低肌肉质量和力量的比例分别达到56.2%和74.5%,女性分别达到35.7%和66.0%。结论 中国成年人肌肉质量和手握力的分布存在明显的地区和人群差异,尤其以老年人低肌肉质量和手握力的比例最高。