BMC Obesity最新文献

Background: This study analysed the relationship between perceived and actual Body Mass Index (BMI) and the effect of a prior identification of obesity by a medical professional for adults using difference in response for two distinct BMI self-perception questions. Typically, self-perception studies only investigate the relation with current weight, whereas here the focus is on the self-perception of weight differences.

Methods: A statistical approach was used to assess responses to the Mexican ENSANUT 2006 survey. Adults in the range of BMI from 13 to 60 were tested on responses to a categorical question and a figure rating scale self-perception question. Differences in response by gender and identification of obesity by a medical professional were analysed using linear regression.

Results: Results indicated that regardless of current BMI and gender, a verbal intervention by a medical professional will increase perceived BMI independently of actual BMI but does not necessarily make the identified obese more accurate in their BMI estimates. A shift in the average self-perception was seen with a higher response for the identified obese. A linear increase in perceived BMI as a function of actual BMI was observed in the range BMI < 35 but with a rate of increase much less than expected if weight differences were perceived accurately.

Conclusions: Obese and overweight Mexican adults not only underestimated their weight, but also, could not accurately judge changes in weight. For example, an increase of 5 kg is imagined, in terms of self-image, to be considerably less. It was seen that an identification of obesity by a health care professional did not improve ability to judge weight but, rather, served as a new anchor from which the identified obese judge their weight, suggesting that even those identified obese who have lost weight, perceive their weight to be greater than it actually is. We believe that these results can be explained in terms of two cognitive biases; the self-serving bias and the anchoring bias.

Background: Knowledge is limited on the role the ability to self-regulate plays in the long-term outcome of obesity treatment in children and adolescents with severe obesity. The purpose of this study was to determine whether the ability to self-regulate after an one year intensive, partly inpatient, combined lifestyle intervention is associated with weight loss maintenance in children and adolescents with severe obesity.

Methods: One hundred twenty participants (8-19 years) with an average SDS-BMI of 3.41 and their parents/caregivers were included in an intervention study. As primary determinant of weight loss maintenance, general self-regulation ability was evaluated using two behavioral computer tasks assessing inhibitory control and sensitivity to reward.

Results: There was no association between inhibitory control at T12 and ∆SDS-BMI between T12 and T24 (β = 0.0002; CI 95% = -0.0010-0.0014; P = 0.761). There was also no relation between sensitivity to reward at T12 and ∆SDS-BMI between T12 and T24 (β = -0.0028; CI 95% = -0.0075-0.0019; P = 0.244). None of the psychosocial factors that were examined as moderators, showed a statistically significant interaction, except for parental feeding style (P = 0.023).

Conclusions: The ability to self-regulate after an intensive, partly inpatient, multidisciplinary one year intervention for severe obesity in children and adolescents was not associated with the ability to maintain the achieved weight loss during the following year. Factors that explain the large range of long term outcomes need to be elucidated.

Trial registration: Netherlands Trial Register (NTR1678, registered 20-Feb-2009).

ᅟ: Both sprint interval training (SIT) and high-intensity intermittent training (HIIT) have been described as time-efficient strategies for inducing favourable metabolic and cardiorespiratory adaptations in healthy and diseased participants.

Background: To date, little attention has been given to profiling the potential health benefits of HIIT or modified HIIT training within overweight and obese cohorts with particular focus on inflammation. Within this pilot trial, we tested the hypothesis that 6 sessions of HIIT performed over 2 weeks with 1-2 days' rest would improve aerobic capacity, glucose metabolism and inflammatory profile in an overweight and obese male cohort. Additionally, we profiled the potential health benefits of 4 HIIT sessions performed over the same period.

Methods: 18 overweight or obese males (BMI = 31.2 ± 3.6; V̇O₂ = 30.3 ± 4.4 ml.kg.min^-1) were studied before and 72 h after HIIT. Training sessions consisted of 10 x 1 min intervals at 90% HR_peak separated by 1 min recovery periods. Exercise was performed either 6 (group 1, n = 8) or 4 (group 2, n = 10) times over a 2 week period.

Results: After training no changes were detected from baseline for body composition, aerobic capacity, glucose metabolism or inflammatory profile (p > 0.05) in either group.

Conclusion: Both 6 and 4 sessions of HIIT performed over a 2-week period are ineffective in improving selected health markers within an overweight and obese cohort.

Trial registration: This trial reports data from human participants and was retrospectively registered on 22/02/2017 with the ISRCTN registry, trial number ISRCTN90672085.

Background: Resting metabolic rates (RMR) vary across individuals. Understanding the determinants of RMR could provide biological insight into obesity and its metabolic consequences such as type 2 diabetes and cardiovascular diseases.

Methods: The present study measured RMR using reference standard indirect calorimetry and evaluated genetic variations from an exome array in a sample of children and adults (N = 262) predominantly of African and European ancestry with a wide range of ages (10 - 67 years old) and body mass indices (BMI; 16.9 - 56.3 kg/m² for adults, 15.1 - 40.6 kg/m2 for children).

Results: Single variant analysis for RMR identified suggestive loci on chromosomes 15 (rs74010762, TRPM1, p-value = 2.7 × 10-6), 1 (rs2358728 and rs2358729, SH3D21, p-values < 5.8x10-5), 17 (AX-82990792, DHX33, 5.5 × 10-5) and 5 (rs115795863 and rs35433829, C5orf33 and RANBP3L, p-values < 8.2 × 10-5). To evaluate the effect of low frequency variations with RMR, we performed gene-based association tests. Our most significant locus was SH3D21 (p-value 2.01 × 10-4), which also contained suggestive results from single-variant analyses. A further investigation of all variants within the reported genes for all obesity-related loci from the GWAS catalog found nominal evidence for association of body mass index (BMI- kg/m²)-associated loci with RMR, with the most significant p-value at rs35433754 (TNKS, p-value = 0.0017).

Conclusions: These nominal associations were robust to adjustment for BMI. The most significant variants were also evaluated using phenome-wide association to evaluate pleiotropy, and genetically predicted gene expression using the summary statistics implicated loci related to in obesity and body composition. These results merit further examination in larger cohorts of children and adults.

Background: Obesity is a pro-inflammatory state that may predispose patients to acute coronary syndrome characterized by chronic low grade inflammation resulting in endothelial dysfunction (ED). The aim of the study was to evaluate urinary biomarkers of inflammation and ED in adolescents with obesity.

Methods: Sixty three subjects were recruited for the study. Twenty healthy adolescents with normal body mass (NW), 14 overweight (OW), 29 obese (OA) subjects were selected. An EndoPat 2000 device was used to measure the reactive hyperemia index (RHI). First morning fasting urine samples were tested for interleukin 6 (IL-6), endothelin 1 (ET-1), alpha-1-acid glycoprotein (AGP), tumor necrosis factor- α (TNF-α) and corrected to urinary creatinine.

Results: Urinary TNF-α was significantly higher in OA group (52.4 ± 15.3 pg/mg) compared to adolescents with NW (14.1 ± 1.2 pg/mg, P = 0.04). ET-1 levels were found to be higher in OW (5.18 ± 1.6 pg/mg) compared with NW (3 · 47 ± 0.3 pg/mg, P = 0.24); and higher in OA (8.48 ± 3.1 pg/mg) compared to both NW (P = 0.19) and OW (P = 0.40). Similarly a higher AGP level was observed in OW (864.8 ± 156 ng/mg) and OA (808.3 ± 186 ng/mg) compared to NW (653 ± 69 ng/mg) (P = 0.16 & 0.49 respectively). Inflammatory markers namely, TNF-α, IL-6 and AGP significantly and positively correlated with each other and with ET-1, a marker for endothelial dysfunction. This significant correlation was also observed when tested separately in the subgroups (NW, OW and OA). There were no differences in RHI levels among the study groups.

Conclusion: Urinary TNF-alpha is significantly elevated in obese adolescents and correlates with urinary ET-1, which is recognized as a biomarker for endothelial dysfunction. Since obesity is a chronic inflammatory state, elevated urinary TNF-alpha might be used as a non invasive tool to monitor the level of that inflammation.

Background: Glucose homeostasis improves within days following Roux-en-Y gastric bypass (RYGB) surgery. The dynamic metabolic response to caloric intake following RYGB has been assessed using liquid mixed meal tolerance tests (MMTT). Few studies have evaluated the glycemic and hormonal response to a solid mixed meal in subjects with diabetes prior to, and within the first month following RYGB.

Methods: Seventeen women with type 2 diabetes of less than 5 years duration participated. Fasting measures of glucose homeostasis, lipids and gut hormones were obtained pre- and post-surgery. MMTT utilizing a solid 4 oz chocolate pudding performed pre-, 2 and 4 weeks post-surgery. Metabolic response to 4 and 2 oz MMTT assessed in five diabetic subjects not undergoing surgery.

Results: Significant reductions in fasting glucose and insulin at 3 days, and in fasting betatrophin, triglycerides and total cholesterol at 2 weeks post-surgery. Hepatic insulin clearance was greater at 3 days post-surgery. Subjects exhibited less hunger and greater feelings of fullness and satisfaction during the MMTT while consuming 52.9 ± 6.5% and 51.0 ± 6.5% of the meal at 2 and 4 weeks post-surgery respectively. At 2 weeks post-surgery, glucose and insulin response to MMTT were improved, with greater GLP-1 and PYY secretion. Improved response to solid MMTT not replicated by consumption of smaller pudding volume in diabetic non-surgical subjects.

Conclusions: With a test meal of size and composition representative of the routine diet of post-RYGB subjects, improved glycemic and gut hormone responses occur which cannot be replicated by reducing the size of the MMTT in diabetic subjects not undergoing surgery.

Trial registration: Clinical Trials.gov Identifier: NCT00957957 August 11, 2009.

Background: The number of bariatric procedures has exponentially increased in the past decade, as a result of the lack of successful clinical weight-loss interventions. The main reasons for the failure of clinical obesity management are: (1) anti-obesity medications are administered as monotherapies (or pre-combined drugs); (2) lack of combination between pharmacotherapy and non-pharmacological modalities; (3) short duration of pharmacotherapy for obesity; (4) lack of weight-loss maintenance strategies; (5) misunderstanding of the complex pathophysiology of obesity; and (6) underprescription of anti-obesity medications. We developed a protocol that can potentially overcome the drawbacks that may lead to the failure of clinical therapy for obesity. The aim of this study is therefore to report the clinical and metabolic effects of our proposed obesity-management protocol over a 2-year period, and to determine whether this more intensive approach to obesity management is feasible and a possible alternative to bariatric surgery in patients with moderate-to-severe obesity.

Methods: This retrospective study involved 43 patients in whom bariatric surgery was indicated. Patients underwent an intensive anti-obesity protocol that included pharmacotherapy with multiple drugs; intense surveillance with monthly body analysis by air-displacement plethysmography, electrical bioimpedance, and 3D body scans; weekly psychotherapy; diet planning with a dietician every 2 months; and exercises at least 3 times a week with exercises prescribed by a personal trainer at least once a month. Body weight (BW), total weight excess (TWE), obesity class, body mass index, fat weight, muscle weight, waist circumference, and visceral fat were analyzed. Markers of lipid and glucose metabolism, liver function, and inflammation were also evaluated. Therapeutic success was defined as >20% BW loss or >50% decrease in TWE after 1 year.

Results: Significant improvements were observed in all clinical and metabolic parameters. Thirty-eight (88.4%) patients achieved 10% BW loss, and 32 (74.4%) achieved 20% BW loss. TWE decreased by >50% in 35 (81.4%) patients. Forty (93.0%) patients were able to avoid bariatric surgery.

Conclusion: An intensive clinical approach to obesity management can be an effective alternative to bariatric surgery, although further randomized controlled studies are necessary to validate our findings.