Sedentarism affects body fat mass index and fat-free mass index in adults aged 18 to 98 years

OBJECTIVE: Body mass index does not discriminate body fat from fat-free mass or determine changes in these parameters with physical activity and aging. Body fat mass index (BFMI) and fat-free mass index (FFMI) permit comparisons of subjects with different heights. This study evaluated differences in body mass index, BFMI, and FFMI in physically active and sedentary subjects younger and older than 60 y and determined the association between physical activity, age, and body composition parameters in a healthy white population between ages 18 and 98 y. METHODS: Body fat and fat-free mass were determined in healthy white men (n = 3549) and women (n = 3184), between ages 18 and 98 y, by bioelectrical impedance analysis. BFMI and FFMI (kg/m2) were calculated. Physical activity was defined as at least 3 h/wk of endurance-type activity for at least 2 mo. RESULTS: Physically active as opposed to sedentary subjects were more likely to have a low BFMI (men: odds ratio [OR], 1.4; confidence interval [CI], 0.7-2.5; women: OR 1.9, CI 1.6-2.2) and less likely to have very high BFMI (men: OR, 0.2; CI, 0.1-0.2; women: OR, 0.1; CI, 0.02-0.2), low FFMI (men: OR, 0.5; CI, 0.3-0.9; women: OR, 0.7; CI, 0.6-0.9), or very high FFMI (men: OR, 0.6; CI, 0.4-0.8; women: OR, 0.7; CI, 0.5-1.0). Compared with subjects younger than 60 y, those older than 60 y were more like to have very high BFMI (men: OR, 6.5; CI, 4.5-9.3; women: OR, 14.0; CI, 9.6-20.5), and women 60 y and older were less likely to have a low BFMI (OR, 0.4; CI, 0.2-0.5). CONCLUSIONS: A clear association was found between low physical activity or age and height-normalized body composition parameters (BFMI and FFMI) derived from bioelectrical impedance analysis. Physically active subjects were more likely to have high or very high or low FFMI. Older subjects had higher body weights and BFMI.     

Fat-free mass in chronic illness: comparison of bioelectrical impedance and dual-energy x-ray absorptiometry in 480 chronically ill and healthy subjects.

Assessment of fat-free mass (FFM) and fat mass in ambulatory and hospitalized patients permits optimal adaptation of nutrition support. Recent methods for the determination of FFM are dual-energy x-ray absorptiometry (DXA) and bioelectrical impedance analysis (BIA). The purpose of this study was to determine if the BIA-determined FFM as estimated by the formula by Kotler et al. and the Geneva formula could be validated when compared to DXA-determined FFM in subjects with various diagnoses. Body composition was measured by BIA and DXA in 480 subjects including healthy young men and women, elite female runners, and patients with various pathologies (including chronic obstructive and restrictive pulmonary disease patients; cystic fibrosis patients; lung, heart, and liver transplantation patients [both pre- and post-], and hemiplegic and AIDS patients). The present results suggest that BIA is relevant in the clinical assessment of body composition, but BIA formulas appropriate to the subject pool must be used for evaluation of FFM and fat mass. The BIA formula by Kotler et al. is appropriate for healthy subjects and patients with AIDS, cystic fibrosis, and pre- or postliver transplantation. The Geneva formula is more appropriate in pulmonary diseases and hemiplegic subjects with normal weight.     

Fat-free mass in relation to stature: ratios of fat-free mass to height in children, adults, and elderly subjects

A cross-sectional relationship of fat-free mass to height expressed as a ratio (FFM:ht) is presented for 1103 people aged 6-86 y. Data are presented for 13 specific age groups by gender. By providing information for normal, healthy individuals, these data may be of comparative value for nutritionists and clinicians concerned with body composition of patients with wasting diseases. The data were collected over 20 y in our laboratory by using the same densitometric procedure. A significant increase in FFM:ht occurs during the preadolescent and adolescent years. The adolescent spurt continues for a longer period for boys than for girls, resulting in a significant gender difference beginning at approximately age 16 y and continuing throughout adulthood. A decline in FFM:ht, not statistically significant, appears to occur in men greater than 60 y of age, and a significant decline occurs among women greater than 50 y of age (alpha less than 0.01). Thus, both gender- and age-related trends that have implications for the interpretation of comparative body-composition status are suggested.     

Validation of air-displacement plethysmography for estimation of body fat mass in healthy elderly subjects

Summary.Background: Air-displacement plethysmography (ADP) is a non-invasive method for body composition analysis that divides the body into fat-free mass (FFM) and fat mass (FM) (= 2 compartment model, 2C). It places low demands on subject performance and is therefore most convenient in the elderly.Objective: To validate ADP against dual energy X-ray absorptiometry (DEXA) and to compare it to a four-compartment model of body composition (4C; fat mass, total body water, bone mineral content and residual mass) in the elderly.Methods: Body composition was assessed by ADP, DEXA and bioelectrical impedance analysis (BIA) in 26 healthy elderly subjects (15 women, 11 men) aged 60–82 years.Results: Despite a high correlation of %FM assessed by ADP and DEXA we observed significant differences between the results of these methods for both sexes (2.5 ±3.4%; bias ± SD). Deviations of %FM_ADP from %FM_DEXA were dependent on bone mineral content (BMC_DEXA) fraction of FFM. A low BMC_DEXA was related to an overestimation of DEXA-derived %FM by ADP. There was a systematic bias between results from ADP and the 4C model. 76% of its variance was explained by the assumption of a fixed density of FFM. 96% of the variance in the density of FFM was explained by water content and only 4% by BMC_DEXA of FFM. When compared to a 4C model, overestimation of %FM_ADP increases with increasing water fraction of FFM.Conclusion: Although there is a tendency for overestimation of %FM_ADP,ADP is a valid method for body composition measurement in the elderly. The bias in %FM_ADP is mainly related to water content of FFM and indicates that a correction factor for TBW may improve the accuracy of the ADP measurements in the elderly.     

广州市6~9岁儿童肌肉及脂肪含量与分娩方式的关系

分析分娩方式与儿童肌肉及脂肪含量的关系,为探索促进儿童健康生长发育的有效途径提供参考.方法 在广州市招募423名6~9岁儿童,通过面对面访谈获取儿童分娩方式等信息,采用双能X线吸收法(DXA)测量四肢肌肉含量(ASM)、全身肌肉含量(TSM)、四肢脂肪含量(AFM)、全身脂肪含量(TFM)和去头骨矿物质含量(TBLH BMC),并测量身高、体重,计算体质量指数(BMI)、四肢肌肉含量指数(AFM/ASM,ASM/体重)、全身肌肉含量指数(TFM/TSM,TSM/体重)及体脂含量指数(FMI).应用协方差校正混杂因素后分析分娩方式与儿童上述指标的关系.结果 顺产组、非选择性剖宫产组和选择性剖宫产组男童的ASM,AFM,TSM,TFM,TFM/TSM,TBLH BMC,FMI差异均有统计学意义(P值均<0.05);与顺产组相比较,选择性剖宫产组儿童ASM,AFM,TSM,TFM,TFM/TSM,TBLH BMC,FMI分别增加了8.31%,37.02%,8.20%,40.00%,18.42%,7.08%,31.50%(P值均<0.05).各组女童上述指标差异均无统计学意义(P值均>0.05).结论 相较于顺产儿童,选择性剖宫产与男童四肢和全身肌肉及脂肪含量较高密切关联,且脂肪含量的增加更为显著,但对女童肌肉和脂肪含量均无明显影响.     

Reference values of ventilatory variables for healthy adolescents aged 15-19 years

The main goal of this investigation was the formation of the reference values of ventilatory variables for group of adolescents of both sexes at the age between 15 and 19 years, what was done for the first time for the region of Vojvodina. These values are important in evaluation of respiratory data obtained from patients in the everyday routine examinations. The investigation was carried out on 1151 healthy school children--nonsmokers having the same ethnic origin from the region of Vojvodina. There were 567 males and 584 female participants. Vitalograph dry spirometer (Vitalograph Ltd, Moreton House, Buckingham, England) was used in these examinations. The whole procedure was explained and demonstrated to the participants and best results of their consecutive attempts were taken for further statistical analysis, ie., for calculations of the mean, SD, SEM, coefficient of variation and linear regression. All tests were performed in the morning hours between 8-12 a.m. The results obtained served for calculating the reference values of forced vital capacity (FVC), volume expired in first second of FVC (FEV1.0) and forced midexpiratory flow (FMF). A positive correlation between the respiratory variables and the body height values was found in all groups of participants. The equations of the linear regression related to the ventilatory variables and the height (in 5 cm intervals) were formed separately for both genders. Analysis of the data shows significant differences of the values for all respiratory variables between males and females, which increased with the increasing height of the person. The values for the male group were always higher. In taller volunteers the difference between the sexes becomes even statistically significant, what points that it is necessary to calculate the equations for each gender separately.     

扎赉诺尔区1~15岁3种疫苗免疫效果检测分析

目的通过对儿童免疫规划三种疫苗免疫后抗体阳性率进行监测分析,总结其免疫效果。方法选取扎赉诺尔区1~15岁4 096名接种3种疫苗的儿童作为研究对象,采用酶联免疫法检测麻疹、风疹、脊髓灰质炎病毒IgG抗体。记录相关数据,进行统计分析。结果被监测的4 096例儿童中,3种疫苗的平均抗体阳性率分别为:麻疹96.00%、风疹96.73%、脊髓灰质炎病毒95.43%;从总体阳性率来看,三种疫苗抗体阳性率之间差异有统计学意义(P=0.011,P0.05)。不同年龄组脊髓灰质炎病毒-IgG抗体阳性率之间差异有统计学意义(P=0.000,P0.05)。不同年龄组麻疹-IgG抗体阳性率之间差异有统计学意义(P=0.000,P0.05)。不同年龄组风疹-IgG抗体阳性率之间差异无统计学意义(P=0.113,P0.05)。三种疫苗不同性别抗体阳性率均无统计学意义。不同性别脊髓灰质炎病毒-IgG抗体阳性率之间差异无统计学意义(P=0.240,P0.05)。不同性别麻疹-IgG抗体阳性率之间差异有统计学意义(P=0.000,P0.05)。不同性别风疹-IgG抗体阳性率之间差异有统计学意义(P=0.000,P0.05)。结论扎赉诺尔区1~15岁儿童3种疫苗3种抗体阳性率均维持在较高水平。     

Self-reported organic and nonorganic sleep problems in schoolchildren aged 11 to 15 years in Vienna.

PURPOSE: To estimate the prevalence of self-reported sleep problems, to examine associations among demographic characteristics, familial factors, and sleep problems, and to investigate the association between the symptoms of obstructive sleep apnea (OSA) and nonorganic sleep disorders. METHODS: An anonymous questionnaire with 22 questions was designed. 332 schoolchildren (aged 11-15 years, mean age 12 years and 9 months; median, 12 years; 56% female, 44% male) from two high schools in Vienna were investigated with regard to self-reported symptoms characteristic for obstructive sleep apnea and for parasomnia/insomnia. Data were analyzed by definition of three groups (problem, occasional problem, and nonproblem sleepers, and by calculation of an insomnia/parasomnia sum score). Statistical analysis included nonparametric tests (Mann Whitney-U and Kruskal), Pearson correlation test, and multiple regression analysis. RESULTS: Twelve percent reported at least one sleep problem every night, 76% reported occasional sleep problems, and 12% had no sleep problems. Girls were affected more frequently than boys (p <.01). Children with sleep problems suffered more often from concentration difficulties (p <.05), daytime fatigue (p <.001), and daytime naps (p <.05). Children who snored had nightmares (10% vs. 2%, p <.01), night terrors (4% vs. 1.5%, p <.001), sleepwalking (1.4% vs. 1%, p <.05), and nocturnal awakening (16% vs. 5%, p <.01) more frequently. On multiple regression analysis, 23% of the variability of a defined parasomnia/insomnia sum score had the characteristic OSA symptoms of nocturnal sweating, dryness of the mouth, snoring, hyperactivity, and daytime fatigue. CONCLUSION: 12% of schoolchildren aged 11-15 years reported sleep problems almost every night. The children suffer from daytime fatigue, naps, and concentration difficulties. Nearly one-fourth of the symptoms of parasomnia/insomnia were associated with characteristic signs of OSA, suggesting the importance of a routine clinical investigation in children with so-called nonorganic sleep disorders.     

The effects of sulfur dioxide on pulmonary function in healthy nonsmoking male subjects aged 55 years and older

To determine whether normal nonsmoking individuals aged 55 years or greater have heightened bronchial reactivity to inhaled SO2, ten male subjects, 55 to 73 years of age, were exposed for 20 min at rest and 10 min during moderate exercise on a treadmill to the following: NaCl droplet aerosol, or 1.0 ppm of SO2 and NaCl droplet aerosol. Seven of the subjects also were exposed to 0.5 ppm SO2 and NaCl droplet aerosol. Significant decrease in forced expiratory volume in one sec (FEV1) were seen 2-3 min post-exercise following all three test modes. The reduction in FEV1 seen after NaCl aerosol + 1.0 ppm SO2 was significantly greater than that seen after NaCl aerosol alone. The results show that men aged 55 years or older are somewhat more sensitive to NaCl aerosol + 1.0 ppm SO2 than similarly exposed normal adolescents, but not nearly as sensitive as asthmatic subjects. This study also demonstrates that investigations of air pollutants and exercise can be undertaken in subjects of this age.     

Reference range of total serum homocysteine level and dietary indexes in healthy Greek schoolchildren aged 6-15 years

Elevated total serum homocysteine (tHcy) may be a possible risk factor for CVD. A 5 micromol/l increase in tHcy is associated with an approximately 70 % increase in relative risk of CVD in adults. Data for children and adolescents are, however, limited. The purpose of the present study was to provide a reference range for tHcy and investigate any relationship between tHcy and nutritional indexes in a Greek paediatric population. tHcy, folate, vitamin B12 levels and dietary indexes were measured in 520 healthy schoolchildren (274 boys, 246 girls) aged 6-15 years. As in adults, the tHcy distribution skewed to the right, with a geometric mean for both genders of 7.4 (range 3.4-29 micromol/l). Concentrations were lower in young children and increased with age. No statistically significant difference in tHcy level was observed between gender. The 95th percentiles for the three age groups were as follows: 6-9 years, 9.98 micromol/l; 10-12 years, 10.62 micromol/l; 13-15 years, 14.4 micromol/l. Using Pearson's coefficient analysis, tHcy level was correlated with age, serum folate, BMI and systolic blood pressure. Dietary analysis showed that folate, vitamin B12 and fibre intake were inversely related with tHcy; conversely, sugar and fat were positively associated with tHcy. However, in multiple linear regression analysis, only age (odds ratio 0.246, P < 0.05) and folate (odds ratio -0.346, P < 0.05) were significantly and independently associated with tHcy. This study provides age-specific reference data regarding tHcy concentration in a Greek paediatric population. tHcy levels increased as a function of age. Serum folate levels were significantly and independently associated with tHcy levels.     

结构甘油三酯与长链甘油三酯在健康志愿者中的代谢研究

目的：通过比较结构甘油三酯与长链甘油三酯在健康志愿者中的代谢效应,以评估结构脂肪乳剂代谢特征。方法：选择１６例健康志愿者进行前瞻性随机交叉对照研究,采用高甘油三酯钳闭技术比较ＳＴＧ和ＬＣＴ的代谢特征。结果;ＳＴＧ的血浆清除率较ＬＣＴ快１倍左右,ＳＴＧ组血清总游离脂到,游离甘油及β－羟基丁酸盐浓度明显高于ＬＣＴ组,血浆脂蛋白脂酶活性明显大于ＬＣＴ组并与所输注的甘油三酯量密切相关。     

郑州市城区7~15岁儿童青少年中心性肥胖流行现况

目的 了解郑州市城区中小学生超重肥胖和中心性肥胖的流行现况,为城区学生的超重肥胖防控提供参考。方法 采用分层整群抽样方法,于2019年选取郑州市城区小学和初中学校的6 859名7~15岁学生进行问卷调查和体格检查,采用体重指数(BMI)、腰围(WC)和腰围身高比(WHtR)3种指标标准分析中小学生的超重肥胖和中心型肥胖流行现况。用R 4.0.3软件进行t检验、完全随机设计χ²检验、配对χ²检验和加权Kappa一致性检验。结果 以BMI标准筛查郑州市城区中小学生的总体超重和肥胖率分别为14.4%和10.3%,以WC标准和WHtR标准筛查的中心型肥胖率分别为19.4%和14.3%。3种筛查标准对各年龄段男生的肥胖和中心型肥胖检出率均高于女生,差异有统计学意义(P<0.01);10~15岁学生的中心型肥胖检出率均高于7~9岁学生,差异有统计学意义(P< 0.01)。在筛查中小学生中心型肥胖上,WC标准 vs. WHtR标准的Kappa值为0.73,其中7~9岁、10~12岁和13~15岁男生的Kappa值分别为0.84、0.85和0.76,一致性程度较高。结论 郑州市城区7~15岁学生超重肥胖和中心型肥胖状况不容乐观,尤其是男生和小学生应重点关注,应及早开展综合干预进行防控。     

广州市城区6-11岁小学生体脂百分比与体质指数关系的分析

【目的】了解广州市城区小学生体脂的分布情况,分析体脂百分比(percentage of body fat,PBF)和体质指数(body mass index,BMI)的关系,为制定适合我国儿童的肥胖诊断标准提供依据。【方法】抽取广州市2区全日制小学各1所,采用生物电阻抗法对1 036名6~11岁小学生进行体脂含量测定。【结果】广州市男女小学生在各年龄段BMI与PBF呈中、高度相关(r=0.65~0.75)。以PBF与BMI标准判断肥胖的一致性,得统计量Kappa系数K=0.67,表明两种标准所判定的儿童肥胖率具有较强的一致性。【结论】应用中国肥胖工作组提出的分年龄、性别判定儿童肥胖的BMI切点对于确定广州市6~11岁小学生体脂水平具有较好的特异性以及灵敏性。制定我国儿童肥胖的评价标准仍需更深入的研究。     

Adrenocortical activity in healthy children is associated with fat mass

BACKGROUND: Excess endogenous or exogenous cortisol is a potent stimulus for fat gain. OBJECTIVE: We examined whether physiologic variations in endogenous cortisol secretion may be associated with changes in body composition during growth. DESIGN: Anthropometric measurements and 24-h excretion rates of urinary free cortisol (UFF) and cortisone (UFE) and the sum of 3 major glucocorticoid metabolites (GC), which reflects overall daily cortisol secretion, were determined cross-sectionally in healthy preschool (50 boys and 50 girls aged 4-5 y), late prepubertal (50 boys and 50 girls aged 8-9 y), and pubertal (50 males aged 13-14 y and 50 females aged 12-13 y) subjects. RESULTS: Significant positive associations (P < 0.001) were found between GC excretion and fat mass, percentage body fat, and body mass index by using covariance analysis adjusted for the grouping factors sex and age. The relations between GC and indexes of body fat remained significant (P < 0.05) even after GC was corrected for individual body surface area and the effect of maternal body mass index on fatness was considered. No consistent associations with fat indexes were seen for UFF, UFE, or the ratio of major urinary cortisol to cortisone metabolites, which reflects 11 beta-hydroxysteroid dehydrogenase type 1 activity. CONCLUSIONS: Although direct effects of UFF and UFE on body composition were not shown, our findings strongly suggest that a higher adrenocortical activity is one endocrine-metabolic feature of healthy children with higher body fat. Whether urinary GC is a long-term predictor of fat gain during childhood should be analyzed in future studies.     

Gut emptying affects dietary fat contribution to postprandial lipemia following sequential meals in healthy subjects

OBJECTIVE: The present study examined the kinetic of plasma triacylglycerol (TAG) and gut emptying after sequential ingestion of breakfast and lunch, and the contribution of dietary fat ingested at breakfast to subsequent TAG after lunch. METHODS: Nine subjects ingested a breakfast (0730 h) and a lunch (1200 h) containing 25 and 44 g of fat, respectively. [1-(13)C] palmitate was added in breakfast only. Plasma TAG and chylomicron-TAG (CM-TAG) concentrations and [1-(13)C] palmitate enrichment were sequentially measured. On a consecutive day, an identical breakfast labeled with (123)I-Lipiodol was ingested, followed by a lunch for three controls. (123)I-Lipiodol dynamics was followed in vivo by scintigraphic imaging focused on the stomach, small bowel, and thoracic duct arch. RESULTS: An early rise in plasma and CM-TAG was observed after lunch ingestion. After breakfast, [1-(13)C] palmitate enrichment was maximal 150 and 210 min in plasma TAG and CM-TAG, respectively, decreased thereafter, and increased rapidly (50 min for plasma TAG and 30 min for CM-TAG) after lunch ingestion. Scintigraphic imaging appeared to show that fat ingested at breakfast was retained in part within the gut at lunch time. For the three subjects who ingested a lunch, a decrease of activity in the stomach and small bowel and a tendency for increased activity in the thoracic arch were observed. CONCLUSION: Contribution of fat ingested at breakfast to lipemia after lunch is confirmed. Fat ingested at breakfast was partly retained within the gut and was mobilized after lunch ingestion, as assessed by acceleration of gut emptying and thoracic duct flow after lunch.