Baseline Fat Mass Research Articles

ICU Admission Muscle and Fat Mass, Survival, and Disability at Discharge: A Prospective Cohort Study

Skeletal muscle dysfunction occurring as a result of ICU admission associates with higher mortality. Although preadmission higher BMI correlates with better outcomes, the impact of baseline muscle and fat mass has not been defined. We therefore investigated the association of skeletal muscle and fat mass at ICU admission with survival and disability at hospital discharge. This single-center, prospective, observational cohort study included medical ICU (MICU) patients from an academic institution in the Unites States. A total of 401 patients were evaluated with pectoralis muscle area (PMA) and subcutaneous adipose tissue (SAT) determinations conducted by CT scanning at the time of ICU admission, which were later correlated with clinical outcomes accounting for potential confounders. Larger admission PMA was associated with better outcomes, including higher 6-month survival (OR, 1.03; 95%CI, 1.01-1.04; P< .001), lower hospital mortality (OR, 0.96; 95%CI, 0.93-0.98; P< .001), and more ICU-free days (slope, 0.044 ± 0.019; P= .021). SAT was not significantly associated with any of the measured outcomes. In multivariable analyses, PMA association persisted with 6 months and hospital survival and ICU-free days, whereas SAT remained unassociated with survival or other outcomes. PMA was not associated with regaining of independence at the time of hospital discharge (OR, 0.99; 95%CI, 0.98-1.01; P= .56). In this study cohort, ICU admission PMA was associated with survival during and following critical illness; it was unable to predict regaining an independent lifestyle following discharge. ICU admission SAT mass was not associated with survival or other measured outcomes.

Fat mass, but not fat-free mass, predicts increased foot pain with obesity, independent of bariatric surgery

BackgroundFoot pain is a common manifestation of obesity. ObjectiveTo determine if bariatric surgery is associated with a reduction in foot pain and if body mass index (BMI) or body composition predict a change in foot pain. SettingUniversity hospital. MethodsParticipants with foot pain awaiting bariatric surgery were recruited for this prospective study. Multivariable linear regression was used to determine predictors of change in foot pain between baseline and 6-month follow-up using body composition (fat mass index and fat-free mass index) or BMI, adjusting for, depression, age, sex, and group (surgery versus control). ResultsForty-five participants (38 female), mean ± standard deviation age of 45.7 ± 9.4 years, were recruited for this study. Twenty-nine participants mean ± standard deviation BMI of 44.8 ± 7.0 kg underwent bariatric surgery, while 16 participants mean ± standard deviation BMI of 47.9 ± 5.2 kg were on the waiting list (control). One participant was lost to follow-up. The treatment group lost a mean of 24.3 kg (95% confidence interval [CI] 21.1–27.5), while the control group gained 1.2 kg (95% CI −2.5 to 4.9), respectively. In multivariable analysis, bariatric surgery was significantly associated with reduced foot pain at 6-month follow-up −32.6 points (95% CI −43.8 to −21.4, P < .001), while fat mass index was significantly associated with increased pain at follow-up 1.5 points (95% CI .2 to 2.8, P = .027), after controlling for fat-free mass index, age, sex, and depression. ConclusionsBariatric surgery was significantly associated with reduced foot pain. Higher baseline fat mass index, but not fat-free mass index or BMI, was predictive of increased foot pain at follow-up. Foot pain may be mediated by metabolic, rather than mechanical, factors in bariatric surgery candidates.

Remission of loss of control eating and changes in components of the metabolic syndrome.

Pediatric loss of control (LOC) eating prospectively predicts the worsening of metabolic syndrome components. However, it is unknown if remission of LOC eating is associated with improvements in metabolic health. Therefore, we conducted a secondary analysis of a trial that enrolled adolescent girls with LOC eating, examining whether LOC remission (vs. persistence) at end-of-treatment was associated with changes in metabolic syndrome components at 6-month follow-up. One hundred three adolescent girls (age 14.5±1.7years; BMI-z 1.5±0.3; 56.3% non-Hispanic White, 24.3% non-Hispanic Black) with elevated weight (75th-97th BMI %ile) and reported LOC eating were assessed for metabolic syndrome components at baseline and again six months following the interventions. The main effects of LOC status at end-of-treatment (persistence vs. remission) on metabolic syndrome components (waist circumference, lipids, glucose, and blood pressure) at 6-month follow-up were examined, adjusting for baseline age, depressive symptoms, LOC frequency, fat mass, and height, as well as race, change in height, change in fat mass, and the baseline value of each respective component. Youth with LOC remission at end-of-treatment had lower glucose (83.9±6.4 vs. 86.5±5.8mg/dL; p=.02), higher high-density lipoprotein cholesterol (50.3±11.8 vs. 44.8±11.9mg/dL; p=.01), and lower triglycerides (84.4±46.2 vs. 96.9±53.7mg/dL; p=.02) at 6-month follow-up when compared with youth with persistent LOC, despite no baseline differences in these components. No other component significantly differed by LOC eating status (ps>.05). Reducing LOC eating in adolescent girls may have a beneficial impact on some components of the metabolic syndrome.

Parathyroid hormone in surgery-induced weight loss: no glucometabolic effects but potential adaptive response to skeletal loading.

Increased parathyroid hormone (PTH) is commonly associated with obesity, and its role in the pathogenesis of obesity-related glucometabolic abnormalities is uncertain. We aimed to explorethe relationships of PTH with glucose/insulin homeostasis parameters before and after bariatric surgery-induced weight loss, and whether they depend or not on 25-hydroxyvitamin D (25OHD) status. We included 42 subjects (27 women, aged 40 ± 5 years, BMI 48.5 ± 7.3 kg/m2) without diabetes, chronic kidney disease, or hyperparathyroidism undergoing sleeve gastrectomy. The following parameters were evaluated before and 6 months after surgery: circulating levels of PTH, calcium, phosphorus, 25OHD, leptin, insulin growth factor (IGF)-1; 75-g oral glucose tolerance test to derive measures of insulin sensitivity (ISI) and secretion (Stumvoll index); dual-energy X-ray absorptiometry to assess fat distribution and bone mineral density. Weight loss was accompanied by significant reduction of PTH levels (77.9 ± 19.1 vs. 60.5 ± 13.4 pg/ml; p = 0.005), without concomitant modification of 25OHD status. Both baseline PTH and its postoperative percent change resulted associated, with baseline fat mass (β = 0.615, p = 0.003) and its concurrent postoperative reduction (r = 0.419; p = 0.006), but neither with glucose homeostasis parameters nor their respective variations after weight loss. Interestingly, leptin reduction after weight loss was independently related to PTH change (β = 0.396, p = 0.015) and IGF-1 levels (β = 0.176, p = 0.059). Circulating PTH decreases with fat mass reduction independent of 25OHD status, but it is not associated with improvement of insulin resistance and related metabolic parameters. Leptin and PTH may mediate the cross-talk between adipose tissue and parathyroid glands, which possibly contributes to bone adaptation to excess body weight.

The 24-Month Changes in Body Fat Mass and Adipokines in Patients Starting Peritoneal Dialysis.

♦ BACKGROUND: Peritoneal dialysis (PD) is characterized by a gain in fat mass. The fat tissue is a complex endocrine organ that releases various adipokines. In this study, we prospectively examined serial changes of fat composition and adipokines in patients undergoing PD. ♦ METHODS: Body composition was assessed by computed tomography (CT). Nutrition status and adipokines (leptin, adiponectin, interleukin [IL]-6, and tumor necrosis factor [TNF]-α) were assessed on the 7th day and 6 months, 12 months, and 24 months after the start of PD. ♦ RESULTS: Fifty-four patients (28 men), with a mean age of 53.2 ± 13.2 years, were enrolled. Baseline fat mass, especially subcutaneous fat mass, was correlated with baseline leptin (ρ = 0.612), adiponetin (ρ = -0.477), and interleukin-6 (IL-6) (ρ = 0.391). Visceral fat mass was correlated with leptin (ρ = 0.545) and adiponectin (ρ = -0.514). Baseline adiponectin was negatively correlated with baseline leptin (ρ = -0.363). While body weight and leptin increased during the 24 months, serum adiponectin decreased in that period. The changes in visceral and subcutaneous fat mass were greater in the first 12 months and 6 months, respectively. There was no difference in IL-6 and TNF-α. Eight patients died during the follow-up period (mean 47.4 months). Twenty-seven patients continued PD. Increased baseline and serial change of IL-6 level were risk factors for mortality. After adjusting for age, sex, diabetes mellitus (DM), and coronary vascular disease (CVD), the significance of the IL-6 level disappeared. ♦ CONCLUSIONS: Baseline subcutaneous fat in patients starting PD is correlated with baseline adipokine levels rather than visceral fat. The increase in subcutaneous fat was greatest in the first 6 months. While leptin and adiponectin increased and decreased respectively, IL-6 did not change in the first 24 months.

Cardiometabolic risk factors in type 2 diabetes with high fat and low muscle mass: At baseline and in response to exercise.

To examine the interplay between high fat and low muscle mass on cardiometabolic risk factors at baseline and in response to exercise in type 2 diabetes. Using baseline percent body fat and skeletal muscle mass index, 248 participants were divided into high fat versus low fat and low muscle versus high muscle. Linear mixed models were used to examine the main effects of fat mass and muscle mass and their interaction on baseline cardiometabolic risk factors and changes in risk factors in response to 6-month exercise training. At baseline, there was a fat mass by muscle mass interaction effect on hemoglobin A1c (HbA1c ; P = 0.009), suggesting that low muscle was associated with elevated HbA1c in those with high fat but not low fat. Significant interactions between baseline fat mass and muscle mass on the exercise-induced changes in visceral adipose tissue, insulin resistance, and triglyceride concentration indicated that low muscle attenuated the exercise responses in participants with high fat at baseline (all P < 0.05). High fat and low muscle may be synergistically associated with higher HbA1c in type 2 diabetes. In participants with high fat mass, low muscle mass may attenuate exercise-induced improvements in some cardiometabolic risk factors.

Effect of Testosterone Treatment on Adipokines and Gut Hormones in Obese Men on a Hypocaloric Diet.

Context:In obese men with lowered testosterone levels, testosterone treatment augments diet-associated loss of body fat.Objective:We hypothesized that testosterone treatment modulates circulating concentrations of hormonal mediators of fat mass and energy homeostasis in obese men undergoing a weight loss program.Design:Prespecified secondary analysis of a randomized, double-blind, placebo-controlled trial.Setting:Tertiary referral center.Participants:Obese men (body mass index ≥30 kg/m2) with a repeated total testosterone level ≤12 nmol/L.Intervention:One hundred participants mean age 53 years (interquartile range 47 to 60 years) receiving 10 weeks of a very low–energy diet followed by 46 weeks of weight maintenance were randomly assigned at baseline to 56 weeks of intramuscular testosterone undecanoate (cases, n = 49) or matching placebo (controls, n = 51). Eighty-two men completed the study.Main outcomes:Between-group differences in leptin, adiponectin, ghrelin, glucagon like peptide-1, gastric inhibitory polypeptide, peptide YY, pancreatic polypeptide, and amylin levels.Results:At study end, compared with controls, cases had greater reductions in leptin [mean adjusted difference (MAD), −3.6 ng/mL (95% CI, −5.3 to −1.9); P < 0.001]. The change in leptin levels between cases and controls was dependent on baseline fat mass, as the between-group difference progressively increased with increasing fat mass [MAD, −0.26 ng/mL (95% CI, −0.31 to −0.26); P = 0.001 per 1 kg of baseline fat mass]. Weight loss–associated changes in other hormones persisted during the weight maintenance phase but were not modified by testosterone treatment.Conclusions:Testosterone treatment led to reductions in leptin beyond those achieved by diet-associated weight loss. Testosterone treatment may reduce leptin resistance in obese men.

Dysglycemia associations with adipose tissue among HIV-infected patients after 2 years of antiretroviral therapy in Mwanza: a follow-up cross-sectional study

BackgroundData on the burden of dysglycemia among HIV-infected patients on antiretroviral therapy (ART) in Africa are limited. We determined the prevalence of pre-diabetes and diabetes among HIV-infected patients who started ART when malnourished 2 to 3 years previously and investigated the association of dysglycemia with body composition.MethodsMalnourished (body mass index (BMI) < 18.5 kg/m2) HIV-infected patients who were enrolled in the Nutritional Support for Africans Starting Antiretroviral Therapy (NUSTART) trial from 2011 to 2013 were followed-up from March to August 2015. Anthropometric, fat mass and fat-free mass by bioelectrical impedance, and C-reactive protein (CRP) data were collected at baseline and follow-up. At follow-up, we defined fasting glucose of 6.1–6.9 mmol/L as impaired fasting glucose (IFG) and 2-h oral glucose tolerance test (OGTT) glucose of ≥7.8 to <11.1 mmol/L as impaired glucose tolerance (IGT). Both of these were considered pre-diabetes. Fasting glucose of ≥7.0 mmol/L or impaired glucose tolerance of ≥11.1 mmol/L was defined as diabetes mellitus. The relation of pre-diabetes and diabetes with body composition was assessed using logistic regression.ResultsTwo hundred seventy-three (57%) of 478 patients who were alive at trial conclusion were followed-up. The mean age was 41.5 (SD 9.8) years and 65.2% (178) were females. The mean follow-up BMI was 19.9 (SD 2.8) kg/m2, 12 (4.4%) were either overweight or obese, and 61 (22.3%) patients had pre-diabetes or diabetes. In multiple regression, upper tertiles of baseline hip circumference (OR: 0.41, 95% CI: 0.2, 0.8) and fat mass index (OR: 0.20 (0.1, 0.5), and upper tertiles of follow-up waist circumference (OR: 0.22 (0.1, 0.5), BMI (OR: 0.32 (0.1, 0.7), fat mass index (OR: 0.19 (0.1, 0.5) and the middle tertile of follow-up fat-free mass (OR: 0.36, 95% CI: 0.1, 0.8) were associated with lower risk of pre-diabetes and diabetes (P < 0.05 for all). Baseline and follow-up CRP were not predictors.ConclusionsLow rather than high measures of adipose tissue were associated with increased risk of pre-diabetes and diabetes. Additional studies are needed to further investigate the role of body composition and control of glucose metabolism in the pathogenesis of diabetes among persons living with HIV in Africa.

High Dose Omega-3 Fatty Acid Administration and Skeletal Muscle Protein Turnover in Maintenance Hemodialysis Patients.

Protein energy wasting and systemic inflammation are prevalent in maintenance hemodialysis (MHD) patients. Omega-3 (ω-3) fatty acids have anti-inflammatory properties and have been shown to improve protein homeostasis. We hypothesized that administration of high-dose (2.9 g/d) ω-3 would be associated with decreased muscle protein breakdown in MHD patients with systemic inflammation. This is a substudy from a randomized, placebo-controlled study (NCT00655525). Patients were recruited between September 2008 and June 2011. Primary inclusion criteria included signs of chronic inflammation (average C-reactive protein of ≥5 mg/L over three consecutive measurements), lack of active infectious or inflammatory disease, no hospitalization within 1 month prior to the study, and not receiving steroids (>5 mg/d) and/or immunosuppressive agents. The primary outcomes were forearm muscle and whole body protein breakdown and synthesis before and after the intervention. The patients received ω-3 (n=11) versus placebo (n=9) for 12 weeks. Analysis of covariance was used to compare outcome variables at 12 weeks. Models were adjusted for a propensity score that was derived from age, sex, race, baseline high sensitivity C-reactive protein, diabetes mellitus, and fat mass because the groups were not balanced for several characteristics. Compared with placebo, ω-3 supplementation was significantly associated with decreased muscle protein breakdown at 12 weeks (-31, [interquartile range, -98--13] versus 26 [interquartile range, 13-87] µg/100 ml per min; P=0.01), which remained significant after multivariate adjustment (-46, [95% confidence interval, -102 to -1] µg/100 ml per min). ω-3 Supplementation resulted in decreased forearm muscle protein synthesis while the rate in the placebo group increased; however, there is no longer a statistically significant difference in skeletal muscle protein synthesis or in net protein balance after multivariate adjustment. There was no statistically significant effect of ω-3 supplementation on whole body protein synthesis or breakdown. High-dose ω-3 supplementation over 12 weeks in MHD patients with systemic inflammation was associated with attenuation of forearm muscle protein breakdown but did not influence skeletal muscle protein synthesis, skeletal muscle net protein balance or any component of the whole-body protein balance. These results should be interpreted cautiously given the imbalance in the two groups and the short duration of the intervention.

Associations between body composition measurements of obesity and radiographic osteoarthritis in older adults: Data from the Dong-gu Study

BackgroundWe examined the effects of fat deposition on radiographic osteoarthritis (OA) to determine the role of obesity in the pathogenesis of radiographic OA.MethodsData were taken from the Dong-gu cohort, a cross-sectional study of 2,367 subjects. Baseline characteristics, waist circumference (WC), waist-to-hip ratio (WHR), fat mass, and fat percentage were collected, along with X-rays of the knees and hands. Total knee and hand radiographic OA scores were summed using a semi-quantitative grading system, and then stratified by gender using a multiple linear regression model.ResultsAfter adjusting for confounders, weight was the only factor significantly associated with knee radiographic OA, regardless of gender (all p < 0.01). Regarding the hand, fat percentage had the largest effect on radiographic OA in males (p = 0.008), while WHR was the most significant factor in females (p = 0.001). For the knee, fat mass was the most important factor for radiographic OA in males (p = 0.001), while in females, body mass index was the most important factor (p < 0.001). Among the variables, only fat percentage was significantly related to both hand and knee radiographic OA in both genders (all p < 0.01).ConclusionsRegardless of gender, weight was significantly associated with knee radiographic OA. Otherwise, fat deposition correlated with hand and knee radiographic OA in both genders, while the distribution of fat tissue was significantly associated with hand and knee radiographic OA only in females.

Polygenic Risk, Appetite Traits, and Weight Gain in Middle Childhood: A Longitudinal Study.

Genome-wide association studies have identified genetic risks for obesity. These genetic risks influence development of obesity partly by accelerating weight gain in childhood. Research is needed to identify mechanisms to inform intervention. Cross-sectional studies suggest appetite traits as a candidate mechanism. Longitudinal studies are needed to test whether appetite traits mediate genetic influences on children's weight gain. To test whether genetic risk for obesity predicts accelerated weight gain in middle childhood (ages 4-8 years) and whether genetic association with accelerated weight gain is mediated by appetite traits. Longitudinal study of a representative birth cohort at the Trondheim Early Secure Study, Trondheim, Norway, enrolled at age 4 years during 2007 to 2008, with follow-ups at ages 6 and 8 years. Participants were sampled from all children born in 2003 or 2004 who attended regular community health checkups for 4-year-olds (97.2% attendance; 82.0% consent rate, n = 2475). Nine hundred ninety-five children participated at age 4 years, 795 at age 6 years, and 699 at age 8 years. Analyses included 652 children with genotype, adiposity, and appetite data. Outcomes were body mass index and body-fat phenotypes measured from anthropometry (ages 4, 6, and 8 years) and bioelectrical impedance (ages 6 and 8 years). Genetic risk for obesity was measured using a genetic risk score composed of 32 single-nucleotide polymorphisms previously discovered in genome-wide association studies of adult body mass index. Appetite traits were measured at age 6 years with the Children's Eating Behavior Questionnaire. Of the 652 genotyped child participants, 323 (49.5%) were female, 58 (8.9%) were overweight, and 1 (0.2%) was obese. Children at higher genetic risk for obesity had higher baseline body mass index and fat mass compared with lower genetic risk peers, and they gained weight and fat mass more rapidly during follow-up. Each SD increase in genetic risk score was associated with a 0.22-point increase in BMI at age-4 baseline (for the intercept, unstandardized path coefficient B = 0.22 [95% CI, 0.06-0.38]; P = .008. Children with higher genetic risk scores also gained BMI points more rapidly from ages 4 to 6 years (B = 0.11 [95% CI, 0.03-0.20]; P = .01 ; β = 0.12) and from 6 to 8 years (B = 0.09 [95% CI, 0.00-0.19]; P = .05; β = 0.10), compared with their lower genetic risk peers. Children at higher genetic risk had higher levels of alleged obesogenic appetite traits than peers with lower genetic risk at age 6 years, but appetite traits did not mediate genetic associations with weight gain. The sum of the 5 indirect effects was B = -0.001 (95% CI, -0.02 -0.01); P = .86; β = 0.00. Genetic risk for obesity is associated with accelerated childhood weight gain. Interventions targeting childhood weight gain may provide one path to mitigating genetic risk. However, middle childhood appetite traits may not be a promising target for such interventions. Studies of early-childhood samples are needed to test whether appetite traits explain how genetic risks accelerate growth earlier in development.

Impact of the 8-week Administration of Tofogliflozin for Glycemic Control and Body Composition in Japanese Patients with Type 2 Diabetes Mellitus.

Objective The adverse effects of selective sodium-glucose co-transporter 2 (SGLT2) inhibitors generally appear within about two or three months after treatment initiation in Japan. Therefore, we investigated the impact of tofogliflozin, a class of SGLT2 inhibitors, on glycemic control and body composition during this period in Japanese patients with type 2 diabetes mellitus. Methods This single-arm open-label study enrolled 20 patients. Patients received tofogliflozin 20 mg once daily for 8 weeks. At week 8, changes from baseline in body weight, serum metabolic markers, and body composition were evaluated. Results A total of 17 patients completed the 8-week administration of tofogliflodin. No serious adverse events were noted. Hemoglobin A1c (HbA1c) decreased significantly, from 7.8% to 7.3% with 8-week administration of tofogliflozin. Both the body weight and body mass index (BMI) also decreased. In addition, a decreased renal function of the boundary zone and hemoconcentration were detected. As for body composition, the free fat mass, total body water, extracellular water and intracellular water were all decreased significantly. Interestingly, the amount of fat mass did not change. The degree of improvement in HbA1c was correlated with the baseline fat mass and BMI. Conclusion An eight-week administration of tofogliflozin improved glycemic control and reduced the body weight and free fat mass in type 2 diabetic patients without affecting the fat mass. In this period, the hematocrit level and renal function should be monitored to guard against hemoconcentration and renal impairment, respectively.

Associations between adiposity, hormones, and gains in height, whole-body height-adjusted bone size, and size-adjusted bone mineral content in 8- to 11-year-old children.

We examined fat-independent associations of hormones with height and whole-body bone size and mineral content in 633 school children. IGF-1 and osteocalcin predict growth in height, while fat, osteocalcin, and in girls also, IGF-1 predict growth in bone size. Leptin and ghrelin are inversely associated with bone size in girls. Obesity causes larger bone size and bone mass, but the role of hormones in this up-regulation of bone in obesity is not well elucidated. We examined longitudinal associations between baseline body fat mass (FM), and fat-independent fasting levels of ghrelin, adiponectin, leptin, insulin, insulin-like growth factor-I (IGF-1), osteocalcin, and intact parathyroid hormone, and subsequent changes in height and in whole-body height-adjusted bone area "BAheight" and size-adjusted bone mineral content "BMCsize" in 8- to 11-year-olds. Analyses were carried out separately for boys (n = 325) and girls (n = 308) including data from baseline, 3 and 6months from OPUS School Meal Study. In both sexes: gain in BAheight was positively associated with baseline FM (≥2.05cm(2)/kg, both p ≤ 0.003). Furthermore, gain in height was positively associated with baseline IGF-1 (≥0.02cm/ng/ml, p = 0.001) and osteocalcin (≥0.13cm/ng/ml, p ≤ 0.009); and gain in BAheight was positively associated with baseline osteocalcin (≥0.35cm(2)/ng/ml, p ≤ 0.019). In girls only, gain in BAheight was also positively associated with baseline IGF-1 (0.06cm(2)/ng/ml, p = 0.017) and inversely associated with both baseline ghrelin (-0.01cm(2)/pg/ml, p = 0.001) and leptin (-1.21cm(2)/μg/ml, p = 0.005). In boys, gain in BMCsize was positively associated with osteocalcin (0.18g/ng/ml, p = 0.030). This large longitudinal study suggests that in 8- to 11-year-old children, IGF-1 and osteocalcin predict growth in height, while FM, osteocalcin, and in girls also, IGF-1 predict growth in BAheight. Fat-independent inverse associations of leptin and ghrelin with BAheight in girls' are contrary to proposed growth-stimulating effects of leptin. Osteocalcin in boys predicts gain in BMCsize.

Changes of 25-OH-Vitamin D during Overwintering at the German Antarctic Stations Neumayer II and III.

PurposeHumans in Antarctica face different environmental challenges, such as low ultra-violet radiation, which is crucial for vitamin D production in humans. Therefore we assessed changes in 25-OH-vitamin D serum concentration during 13 months of overwintering at the German Stations Neumayer II and III (2007–2012). We hypothesized that (i) 25-OH-vitamin D serum concentration would significantly decrease, (ii) changes would be affected by age, gender, baseline (i.e. pre-overwintering) fat mass, baseline 25-OH-vitamin D serum concentration, and station residence, and (iii) our results would not differ from similar previous studies in comparable high latitudes.Materials & Methods25-OH-vitamin D serum concentrations were determined before, after, and monthly during the campaigns from venous blood samples of n = 43 participants (28 men, 15 women). Baseline fat mass was determined via bio impedance analysis and body plethysmography. Data were analyzed for change over time, dependency on independent parameters, and after categorization for sufficiency (>50nmol/l), insufficiency (25-50nmol/l), and deficiency (<25nmol/l). Results were compared with data from similar previous studies.ResultsWe found a significant decrease of 25-OH-vitamin D with dependency on month. Age, gender, fat mass, and station residence had no influence. Only baseline 25-OH-vitamin D serum concentrations significantly affected subsequent 25-OH-vitamin D values.ConclusionsOverwinterings at the Antarctic German research stations Neumayer II and III are associated with a decrease in 25-OH-vitamin D serum concentrations, unaffected by age, gender, baseline fat mass, and station residence. Higher baseline vitamin D serum concentrations might protect from subsequent deficiencies. Residence at the Neumayer Stations may lead to lower vitamin D serum concentrations than found in other comparable high latitudes.

Low levels of physical activity are associated with dysregulation of energy intake and fat mass gain over 1 year

Previous studies suggest that appetite may be dysregulated at low levels of activity, creating an energy imbalance that results in weight gain. The aim was to examine the relation between energy intake, physical activity, appetite, and weight gain during a 1-y follow-up period in a large sample of adults. Participants included 421 individuals (mean ± SD age: 27.6 ± 3.8 y). Measurements included the following: energy intake with the use of interviewer-administered dietary recalls and calculated by using changes in body composition and energy expenditure, moderate-to-vigorous physical activity (MVPA) with the use of an arm-based monitor, body composition with the use of dual-energy X-ray absorptiometry, and questionnaire-derived perceptions of dietary restraint, disinhibition, hunger, and control of eating. Participants were grouped at baseline into quintiles of MVPA (min/d) by sex. Measurements were repeated every 3 mo for 1 y. At baseline, an inverse relation existed between body weight and activity groups, with the least-active group (15.7 ± 9.9 min MVPA/d, 6062 ± 1778 steps/d) having the highest body weight (86.3 ± 13.2 kg) and the most-active group (174.5 ± 60.5 min MVPA/d, 10260 ± 3087 steps/d) having the lowest body weight (67.5 ± 11.0 kg). A positive relation was observed between calculated energy intake and activity group, except in the lowest quintile of activity. The lowest physical activity group reported higher levels of disinhibition (P = 0.07) and cravings for savory foods (P = 0.03) compared with the group with the highest level of physical activity. Over 1 y of follow-up, the lowest activity group gained the largest amount of fat mass (1.7 ± 0.3 kg) after adjustment for change in MVPA and baseline fat mass. The odds of gaining >3% of fat mass were between 1.8 and 3.8 times as high for individuals in the least-active group as for those in the middle activity group. These results suggest that low levels of physical activity are a risk factor for fat mass gain. In the current sample, a threshold for achieving energy balance occurred at an activity level corresponding to 7116 steps/d, an amount achievable by most adults. This trial was registered at clinicaltrials.gov as NCT01746186.

Body composition changes in adolescents after laparoscopic sleeve gastrectomy

BackgroundSleeve gastrectomy (SG) is a commonly used bariatric procedure in severely obese adolescents. Weight loss after SG is associated with marked changes in body composition, but factors associated with such changes have not yet been described in adolescents. ObjectiveTo identify factors associated with changes in body weight and composition in adolescents 1 year after SG. SettingUniversity Hospital, Tel Hashomer, Israel. MethodsAge, sex, weight, height, preoperative body mass index (BMI), and body fat percent measured by bioimpedance were collected in 25 adolescents (16 males, 9 females, age 16.6±1.5 yr) before and 1 year after SG. Obesity-related complications, preoperative weight loss, and physical activity after surgery were also recorded. Repeated-measures analyses of variance and linear mixed model analyses were performed. ResultsOne year after SG, weight decreased by 32%, fat mass by 55%, and fat-free mass by 9% from baseline. Male participants lost significantly more weight than female participants, with larger decreases in fat mass (–65% versus –41%, P<.001) and body fat percent (–48% versus –21%, P<.001). The amount of physical activity at 1-year follow-up was also associated with larger reductions in body fat percent in both genders. Age or baseline BMI, fat mass, and fat-free mass were not associated with changes in BMI or body composition. ConclusionAmong obese adolescents 1 year after SG, the only modifiable factor associated with larger decreases in body fat percent was physical activity. Larger studies are needed to formally identify other possible predictors of body composition changes after SG.

Early cartilage abnormalities at the hip are associated with obesity and body composition measures - a 3.0T MRI community-based study.

IntroductionAlthough obesity is a risk factor for hip osteoarthritis (OA), the role of body composition, if any, is unclear. This study examines whether the body mass index (BMI) and body composition are associated with hip cartilage changes using magnetic resonance imaging (MRI) in community-based adults.Methods141 community-based participants with no clinical hip disease, including OA, had BMI and body composition (fat mass and fat free mass) measured at baseline (1990 to 1994), and BMI measured and 3.0 T MRI performed at follow-up (2009–2010). Femoral head cartilage volume was measured and femoral head cartilage defects were scored in the different hip regions.ResultsFor females, baseline BMI (β = −26 mm3, 95% Confidence interval (CI) -47 to −6 mm3, p = 0.01) and fat mass (β = −11 mm3, 95% CI −21 to −1 mm3, p = 0.03) were negatively associated with femoral head cartilage volume. Also, while increased baseline fat mass was associated with an increased risk of cartilage defects in the central superolateral region of the femoral head (Odds Ratio (OR) = 1.08, 95% CI 1.00–1.15, p = 0.04), increased baseline fat free mass was associated with a reduced risk of cartilage defects in this region (OR = 0.82, 95% CI 0.67–0.99; p = 0.04). For males, baseline fat free mass was associated with increased femoral head cartilage volume (β = 40 mm3, 95% CI 6 to 74 mm3, p = 0.02).ConclusionsIncreased fat mass was associated with adverse hip cartilage changes for females, while increased fat free mass was associated with beneficial cartilage changes for both genders. Further work is required to determine whether modifying body composition alters the development of hip OA.

Adipose tissue morphology predicts improved insulin sensitivity following moderate or pronounced weight loss.

Cross-sectional studies show that white adipose tissue hypertrophy (few, large adipocytes), in contrast to hyperplasia (many, small adipocytes), associates with insulin resistance and increased risk of developing type 2 diabetes. We investigated if baseline adipose cellularity could predict improvements in insulin sensitivity following weight loss. Plasma samples and subcutaneous abdominal adipose biopsies were examined in 100 overweight or obese individuals before and 10 weeks after a hypocaloric diet (7±3% weight loss) and in 61 obese subjects before and 2 years after gastric by-pass surgery (33±9% weight loss). The degree of adipose tissue hypertrophy or hyperplasia (termed the morphology value) in each individual was calculated on the basis of the relationship between fat cell volume and total fat mass. Insulin sensitivity was determined by homeostasis model assessment-estimated insulin resistance (HOMAIR). In both cohorts at baseline, subjects with hypertrophy displayed significantly higher fasting plasma insulin and HOMAIR values than subjects with hyperplasia (P<0.0001), despite similar total fat mass. Plasma insulin and HOMAIR were normalized in both cohorts following weight loss. The improvement (delta insulin or delta HOMAIR) was more pronounced in individuals with hypertrophy, irrespective of whether adipose morphology was used as a continuous (P=0.0002-0.027) or nominal variable (P=0.002-0.047). Absolute adipocyte size associated (although weaker than morphology) with HOMAIR improvement only in the surgery cohort. Anthropometric measures at baseline (fat mass, body mass index, waist-to-hip ratio or waist circumference) showed no significant association with delta insulin or delta HOMAIR. In contrast to anthropometric variables or fat cell size, subcutaneous adipose morphology predicts improvement in insulin sensitivity following both moderate and pronounced weight loss in overweight/obese subjects.

Association between fat mass, lean mass, and bone loss: the Dubbo osteoporosis epidemiology study

Lower body fat mass is a risk factor for bone loss at lumbar spine in postmenopausal women, but not in men. Body lean mass and fat mass were not associated with femoral neck bone loss in either gender. Bone density and body mass are closely associated. Whole body lean mass (LM) and fat mass (FM) together account for approximately 95 % of body mass. Bone loss is associated with loss of body mass but which of the components of body mass (FM or LM) is related to bone loss is not well understood. Therefore, in this study, we sought to assess whether baseline FM or LM has predictive value for future relative rate of bone mineral density (BMD) changes (%/year). The present population-based cohort study was part of the ongoing Dubbo Osteoporosis Epidemiology Study (DOES). BMD, FM, and LM were measured with dual energy X-ray absorptiometry (GE-LUNAR Corp, Madison, WI). BMD measurements were taken in approximately every 2 years between 2000 and 2010. We only included the participants with at least two BMD measurements at the femoral neck and lumbar spine. In total, 717 individuals (204 men and 513 women) aged 50 years or older were studied. Rate of bone loss at femoral neck and lumbar spine was faster in women than in men (all P < 0.01). In bivariable regression analysis, each 5 kg greater FM in women was associated with 0.4 %/year (P = 0.003) lower bone loss at lumbar spine. This magnitude of association remained virtually unchanged after adjusting for LM and/or other covariates (P = 0.03). After adjusting for covariates, variation of FM accounted for ∼1.5 % total variation in lumbar spine bone loss. However, there was no significant association between FM and change in femoral neck BMD in either men or women. Lower FM was an independent but modest risk factor for greater bone loss at the lumbar spine in women but not in men. If further studies confirm our findings, FM can help predict lumbar spine bone loss in women.

The role of leptin and other hormones related to bone metabolism and appetite regulation as determinants of gain in body fat and fat-free mass in 8-11-year-old children.

Regulation of body composition during childhood is complex. Numerous hormones are potentially involved. Leptin has been proposed to restrain weight gain, but results are inconsistent. We examined whether baseline fasting levels of ghrelin, adiponectin, leptin, insulin, IGF-I, osteocalcin, and intact parathyroid hormone (iPTH) were associated with body composition cross sectionally and longitudinally in 633 8-11-year-olds. Data on hormones and body composition by dual-energy x-ray absorptiometry from the OPUS School Meal Study were used. We looked at baseline hormones as predictors of baseline fat mass index (FMI) or fat-free mass index (FFMI), and also subsequent changes (3 and 6 months) in FMI or FFMI using models with hormones individually or combined. Cross-sectionally, baseline leptin was positively associated with FMI in girls (0.211 kg/m(2) pr. μg/mL; 97.5% confidence interval [CI],0.186-0.236; P < .001) and boys (0.231 kg/m(2) pr. μg/mL; 97.5% CI, 0.200-0.261; P < .001). IGF-I in both sexes and iPTH in boys were positively associated with FMI. An inverse association between adiponectin and FFMI in boys and a positive association between IGF-I and FFMI were found in girls. In longitudinal models, baseline leptin was inversely associated with subsequent changes in FMI (-0.018 kg/m(2) pr. μg/mL; 97.5% CI, -0.034 - -0.002; P = .028) and FFMI (-0.014 kg/m(2) pr. μg/mL; 97.5% CI, -0.024 - -0.003; P = .006) in girls. Cross-sectional findings support that leptin is produced in proportion to body fat mass, but the longitudinal observations support that leptin inhibits gains in FMI and FFMI in girls, a finding that may reflect preserved leptin sensitivity in this predominantly normal weight population.