Obesity Impact Evaluated from Fat Percentage in Bone Mineral Density of Male Adolescents.
ABSTRACT: OBJECTIVE:To analyze bone mineral density (BMD) values in adolescents and to assess obesity impact, measured through body fat #x2013;on this variable through the assessment by DEXA. METHODOLOGY:A total of 318 males adolescents (12-17 years) were evaluated considering weight, height, body mass index (BMI), bone mineral density (BMD), fat and lean mass. BMD was assessed for the arms, legs, hips, and lumbar regions, as well as for total amount. Stratification of the nutritional status was determined by body fat (%BF) percentage; comparison of groups was scrutinized by analysis of variance; and the association of variables was performed using Pearson's test. RESULTS:There was a progressive increase in weight, height, and BMD for all evaluated age groups following the advance of chronological age. A negative correlation was found between the %BF with BMD in all evaluated segments. Significant differences were found between the eutrophic group compared to the overweight group and the obesity group in the evaluated segments (P <0.01) noting a reduction of up to 12.92% for the lumbar region between eutrophic and obese. CONCLUSION:The results suggest that increase %BF is associated with lower BMD among male adolescents.
Project description:OBJECTIVE:To compare bone mineral density (BMD) and body composition among adolescents: (a) with atypical anorexia nervosa (AAN) versus anorexia nervosa (AN) and (b) those with and without a prior history of overweight. METHOD:Electronic medical records of patients 9-20?years with AN or AAN who underwent dual-energy x-ray absorptiometry scans were retrospectively reviewed and analyzed. RESULTS:A total of 286 adolescents with AN or AAN were included. In linear regression models, AAN was associated with greater Z-scores in whole body bone mineral content (BMC, B?=?0.88, p?<?0.001), lumbar spine BMD (B?=?0.79, p?=?0.002), femoral neck BMD (B?=?0.670, p?=?0.009); fat mass index (B?=?1.33, p?=?0.003), and lean body mass index (LBMI, B?=?1.10, p?<?0.001) compared to AN, adjusting for age, sex, and duration of illness. A prior overweight history was associated with greater Z-scores in whole body BMC; lumbar spine BMD, total hip BMD, femoral neck BMD, and LBMI. DISCUSSION:Adolescents with AAN had higher BMD Z-scores than adolescents with AN; adolescents with a prior overweight history had greater BMD Z-scores than adolescents without a prior overweight history. These findings may inform clinical guidelines for the medical management of AAN.
Project description:In adults, obesity has been associated with several health outcomes including increased bone density. Our objective was to evaluate the association between percent body fat and fat mass with bone mineral density (BMD) in a nationally representative population of children and adolescents.A total of 8,348 participants 8-18 years of age from the National Health and Nutrition Examination Survey (NHANES) 1999-2006 had whole body DXA scans performed. We conducted linear regressions to examine the relationship between percent body fat and fat mass with outcome variables of total body, pelvic and lumbar spine areal BMD (aBMD), controlling for lean body mass and assessing for gender and race/ethnicity interactions.We found evidence of gender and race/ethnicity interactions with percent body fat and total fat mass for the different BMD areas. Generally, there were decreases in total body aBMD (p<0.001) and lumbar spine aBMD (p<0.001) with increasing percent body fat and total fat mass, with less consistent patterns for pelvic aBMD.Our findings of regional differences in the relationship of adiposity to aBMD in children and adolescents with significant interactions by gender and race/ethnicity emphasizes the need for further investigations to understand the impact of adiposity on bone health outcomes.
Project description:Aerobic exercise training has many known cardiovascular benefits that may promote healthy aging. It is not known if long-term aerobic exercise training is also associated with structural benefits (e.g., lower fat mass, higher areal bone mineral density (BMD) and greater muscle mass). We evaluated these parameters in middle-aged long-term endurance runners compared to sex-, age-, height-, and weight-matched non-running controls. Total and regional lean and fat mass and areal BMD were assessed by dual-energy X-ray absorptiometry. Sagittal magnetic resonance images captured the cross-sectional area and thickness of the lumbar multifidus. Runners (n = 10; all male) had a mean (standard deviation; SD) age of 49 (4) years, height of 178.9 (4.9) cm, weight of 67.8 (5.8) kg, body mass index (BMI) of 21.4 (1.4) kg/m2 and had been running 82.6 (27.9) km/week for 23 (13) years. Controls (n = 9) had a mean (SD) age of 51 (5) years, height of 176.0 (5.1) cm, weight of 72.8 (7.1) kg, and BMI of 23.7 (2.1) kg/m2. BMI was greater in controls (p = 0.010). When compared to controls on average, runners had a 10 percentage-point greater total body lean mass than controls (p = 0.001) and 14% greater trunk lean mass (p = 0.010), as well as less total body (8.6 kg; p < 0.001), arm (58%; p = 0.002), leg (52%; p < 0.001), trunk (73%; p < 0.001), android (91%; p < 0.001), and gynoid fat mass (64%; p < 0.001). No differences were observed between groups for BMD outcomes or multifidus size. These results underscore the benefits of endurance running to body composition that carry over to middle-age.
Project description:BACKGROUND: There is evidence in support of low bone density in young patients with disorders of phenylalanine metabolism; however, little is known about muscle and fat mass in these patients, especially in those with mild hyperphenylalaninemia (mHPA). OBJECTIVES: We aimed to evaluate body composition of children and adolescents with early-diagnosed disorders of phenylalanine metabolism. PATIENTS AND METHODS: The study was conducted in the Institute of Child Health, which is the national center that performs newborn screening. Bone, muscle, and fat mass of 48 patients with phenylketonuria (PKU) and 32 patients with mild mHPA, aged five to 18 years, were compared to 57 age- and sex-matched controls. Dual energy X-ray absorptiometry was used for this purpose. RESULTS: Compared to controls, bone mineral density (BMD) was lower in patients with PKU (mean total body BMD z score, 0.11; P = 0.03) and in those with mild mHPA (mean lumbar BMD z score, -0.34; P = 0.01). Lean body mass and fat mass were not significantly affected in the study group. Comparison between the two patients groups did not reveal any difference in body composition profiles; however, pubertal status appeared important for within-group comparisons. Fat mass was significantly increased in teenagers with PKU, which was more evident in those with poor dietary compliance irrespective of gender (fat mass z score, 0.66; P = 0.018). Finally, positive correlations were found not only between bone, muscle, and fat mass in both groups, but also between fat mass and Phenylalanine levels in patients with PKU (r, 0.46; P = 0.001). CONCLUSIONS: Bone mineral density appears suboptimal in young patients with disorders of phenylalanine metabolism. Adolescents seemed more prone to obesity, especially when their dietary adherence was poor, whereas muscle mass was not considerably affected. To ensure healthier bones and less fat content, close follow-up as well as proper lifestyle advice is needed.
Project description:Achondroplasia is a condition characterized by a genetic mutation affecting long bone endplate development. Current data suggests that the bone mineral content (BMC) and bone mineral density (BMD) of achondroplasic populations are below age matched individuals of average stature (controls). Due to the disproportionate limb-to-torso length compared to controls however, the lower BMC and BMD may be nullified when appropriately presented. The aim of this study was to measure whole-body and segmental body composition in adult males with achondroplasia (N = 10, 22 ±3 yrs), present data relative to whole-body and whole-limb values and compare all values to age matched controls (N = 17, 22 ±2 yrs). Dual X-ray absorptiometry (DEXA) was used to measure the in vivo mass of the whole-body and 15 segments, from which BMD, BMC, fat free mass (FFM) and body fat mass were measured. BMC of lumbar vertebrae (L1-4) was also measured and presented as a volumetric BMD (BMDVOL). The achondroplasic group had less BMC, BMD and FFM, and more body fat mass than controls as a whole-body measure. The lower achondroplasic BMC and BMD was somewhat nullified when presented relative to whole-body and whole-limb values respectively. There was no difference in lumbar BMDVOL between groups. Whole-body BMD measures presented the achondroplasic group as 'osteopenic'. When relative to whole-limb measures however, achondroplasic BMD descriptions were normal. Further work is needed to create a body composition database for achondroplasic population's, or for clinicians to present achondroplasic body composition values relative to the whole-limb.
Project description:A longitudinal observational study was performed comparing BMD and body composition in Turner syndrome girls before and after 1 year of HRT treatment. Whole body BMD, femur neck BMD, total hip BMD, and lean mass were significantly increased, but there was no difference in fat mass, and lumbar spine BMD. Purpose: Low bone mineral density (BMD) is one of the major health problems in Turner syndrome (TS) patients, and a certain percentage of TS girls are treated with hormone replacement therapy (HRT) to improve their BMD, among other health benefits. While it is generally accepted that HRT improves BMD and body composition in adolescent and young adult TS patients, studies of HRT in Chinese TS patients are limited. Methods: To investigate the effects of HRT in Chinese TS girls, we performed a longitudinal observational study which compared measurement of BMD and body composition by dual energy X-ray absorptiometry (DXA) using a Lunar DXA densitometer in 20 Chinese adolescent and young adult TS patients (average age = 18) before and after 1 year of HRT treatment. Results: Whole body BMD (0.85 vs. 0.87 g/cm2, P < 0.001), femur neck BMD (0.6 vs. 0.62 g/cm2, P = 0.02), total hip BMD (0.68 vs. 0.71 g/cm2, P = 0.003) and whole body lean mass (30.39 vs. 31.66 kg, P = 0.002) were significantly increased in these patients after 1 year HRT treatment, but there was no difference in whole body fat mass, android:gynoid ratio and lumbar spine BMD. Conclusions: In summary, our study found that HRT was an effective way to increase whole body BMD, femur neck BMD, total hip BMD and whole body lean mass in Chinese TS girls, with no effect on whole body fat mass, android:gynoid ratio or lumbar spine BMD.
Project description:To assess factors associated with bone mineral density (BMD) in postmenopausal women in a longitudinal study, and to examine the relative contribution of lean mass, fat mass, dietary patterns, and years since menopause to BMD.Two hundred and eighty-two postmenopausal women were randomly selected from Hongqi Community Health Center, in Harbin City, China. All participants were followed up from 2009 to 2011. Dietary data were collected using a Food Frequency Questionnaire. BMD of the left hip, the lumbar spine, and the total body, and the body composition were measured by dual-energy X-ray absorptiometry at baseline and follow-up.Lean mass and fat mass were positively associated with BMD of the spine, hip, and the total body at both baseline and follow-up. The association between fat mass and BMD at the spine at baseline (P = 0.210) and at the spine (P = 0.116) and hip (P = 0.073) in the second year was not statistically significant when height was adjusted. Six dietary patterns were identified but only cereal grains-fruits pattern (P = 0.001 in the spine, P = 0.037 in hip) and milk-root vegetables pattern (P = 0.010 in hip) were associated with BMD of the spine and hip. The linear mixed model of follow-up data showed that lean mass, years since menopause, and age of menophania were the significant determinants of BMD of all sites. Moreover, lean mass was the best determinant of BMD (VIP = 1.936).Lean mass, years since menopause, age of menophania and dietary patterns are the important determinants of BMD of the spine, hip, and the total body. Lean mass is the best determinant of BMD.
Project description:To date, the only published reports of bone mineral density (BMD) in MPS IV involve patients with MPS IVA; no reports exist describing BMD for MPS IVB. In this prospective study of BMD in three patients with MPS IVB, BMD was acquired by dual-energy X-ray absorptiometry (DXA) at whole body (WB), lumbar spine (LS), and lateral distal femur (LDF). Functional abilities, ambulatory status, medical history, and height z-score were evaluated. Three patients with MPS IVB (two females), aged 17.7, 31.4 and 31.7 years, were evaluated. Every patient was ambulatory and one sustained two fractures caused by trauma. Whole body and hip DXA scans were technically invalid in every patient due to the presence of prosthetic hip hardware. Lumbar spine was valid in only 1 patient due skeletal abnormalities, and was normal (Z-score of - 0.8). The LDF was valid in every patient and was low at all three regions of interest: average LDF z-scores were - 3.1 (range, - 2.9 to - 3.6), - 2.3 (range, - 2.0 to - 2.5), and - 2.1 (range, - 2.0 to - 2.3) for region 1-region 3, respectively. Patients with MPS IVB have low BMD of the lower extremities even with full-time ambulation. Routine body sites to measure by DXA were problematic; hip and WB were invalid due to artifact, and LS had limited utility. The LDF was the only body site consistently available on all patients. Patients did not experience low-energy fractures despite low BMD.
Project description:Fracture risk is rising in countries undergoing rapid rural to urban migration, but whether this reflects an adverse effect of urbanization on intrinsic bone strength, as reflected by bone mineral density (BMD), is currently unknown.Lumbar spine (LS) and total hip (TH) BMD, and total body fat and lean mass, were obtained from DXA scans performed in the Hyderabad arm of the Indian Migration Study (54% male, mean age 49 years). Sib-pair comparisons were performed between rural-urban migrants (RUM) and rural non-migrated (RNM) siblings (N = 185 sib-pairs).In analyses adjusted for height, gender, age and occupation, rural to urban migration was associated with higher lumbar and hip BMD and greater predicted hip strength; ?LS BMD 0.030 (0.005, 0.055) g/cm2, ?TH BMD 0.044 (0.024; 0.064) g/cm2, ?cross-sectional moment of inertia 0.162 (0.036, 0.289) cm4. These differences were largely attenuated after adjusting for body composition, insulin levels and current lifestyle factors ie. years of smoking, alcohol consumption and moderate to vigorous physical activity. Further analyses suggested that differences in lean mass, and to a lesser extent fat mass, largely explained the BMD differences which we observed.Rural to urban migration as an adult is associated with higher BMD and greater predicted hip strength, reflecting associated alterations in body composition. It remains to be seen how differences in BMD between migration groups will translate into fracture risk in becoming years.
Project description:Introduction:Preterm infants are at increased risk of osteopenia of prematurity due to insufficient bone mineral accretion. Data on long term effects of prematurity on bone health are conflicting. This study aimed to compare bone mineral density (BMD) in young adults born very preterm and full-term controls and to examine factors associated with long-term bone health. Methods:This observational cross-sectional study enrolled 101 young adults (18-29 years) born <29 weeks of gestation and 95 sex- and age-matched full-term controls. Participants underwent dual-energy X-ray absorptiometry to measure areal BMD and body composition. Generalized estimated equations were used to compare groups adjusting for height Z-score, lean body mass and fat mass. Results:Adults born preterm were shorter and lighter than full-term controls. Areal BMD was reduced at the lumbar spine, the femoral neck and whole body in the preterm versus full-term group, but after adjustment, areal BMD Z-score was only significantly lower at the femoral neck by -0.3 unit (95% confidence interval -0.6 to -0.0). Low BMD (Z-score ≤ -1 standard deviation) at any site was observed in 53% of adults born preterm versus 28% of full-term controls, but this was not statistically significantly different. We did not identify any neonatal factors associated with lower BMD within the preterm group. Conclusions:Very preterm birth is associated with lower areal BMD at the femoral neck in young adulthood, even after accounting for body size. Whether this will translate into higher risk of osteoporotic fractures later in life remains unknown.