The Effect of Overweight/Obesity on Cardiovascular Responses to Acute Psychological Stress in Men Aged 50-70 Years

BackgroundTo determine the effect of adiposity in males aged 50-70 years on cardiovascular responses to acute psychological stress.MethodsLean (BMI 20-25 kg/m²) (n = 21) and overweight/obese (BMI 27-35 kg/m²) (n = 21) men aged 50-70 years were subjected to psychological stress. Systolic blood pressure, diastolic blood pressure, heart rate, total peripheral resistance, and cardiac output were measured by a Finometer during resting (60 min), stress (30 min), and recovery (90 min).ResultsThe lean group had a significantly higher SBP stress reactivity when compared to the overweight/obese group (51.5 ± 3.7% vs. 41.0 ± 2.9% (mean ± SEM); p < 0.05). A significant effect of time was observed for systolic blood pressure, diastolic blood pressure, heart rate, total peripheral resistance, and cardiac output (p < 0.0001 for all). There were significant time × body type interactions for systolic blood pressure, diastolic blood pressure, heart rate, total peripheral resistance, and cardiac output (p < 0.05 for all). Total peripheral resistance during recovery was higher in the lean compared to the overweight/obese group (p < 0.05). In the lean group, systolic and diastolic blood pressure variability remained elevated after stress (p < 0.05) but returned to resting levels in the overweight/obese group (p > 0.05).ConclusionModerate adiposity in men was associated with reduced systolic blood pressure % reactivity, total peripheral resistance, and blood pressure variability after psychological stress. Overweight/obese men appear to be at no greater risk of unfavorable cardiovascular responses to stress.Key Words: Stress, Blood pressure, Obesity, Adults     

Dietary Habits and Cardiometabolic Health in Obese Children

BackgroundPrevalence rates of cardiometabolic risk factors vary largely among overweight children. This study investigated the relationships between dietary habits and cardiometabolic health among obese children living in a city of Northern Italy.MethodsDietary habits were collected in 448 obese subjects aged 6-18 years, attending an obesity outpatient center in Milan. Anthropometry, blood pressure (BP), lipids, fasting and post-load glucose, and insulin were measured. Physical activity was assessed in adolescents using a questionnaire.ResultsFrequency of glucose intolerance, hypertension and dyslipidemia was 0.7%, 13% and 27.2%, respectively. Plausible reporters consumed more animal protein and sodium and less legumes than recommended in nutritional recommendations and adequate amounts of fiber mainly derived from whole grains. Subjects skipping breakfast had unhealthy diets and greater body fatness. After adjustment for confounders, waist/height and fasting glucose were associated with sodium intake (r =0.149 and r = 0.142, respectively; p < 0.05), 2-hour glucose with fiber (r = −0.172; p < 0.01), and BP with vegetable protein intake (systolic r = −0.120 (p < 0.05); diastolic r = −0.267 (p < 0.01)). Hypertensive children consumed less vegetable protein than normotensive children.ConclusionsThe cardiometabolic health of obese children improves with vegetable protein and whole grain intake, whereas dysglycemia and adiposity increase with sodium intake.Key Words: Dietary habits, Childhood obesity, Glucose metabolism, Hypertension, Cardiometabolic risk     

Correlation of Resistin with Inflammatory and Cardiometabolic Markers in Obese Adolescents with and without Metabolic Syndrome

ObjectiveThe link between plasma resistin and obesity-related cardiometabolic disorders in children remains debatable. This study assessed the relationships of plasma resistin with cardiovascular risk factors, pro-inflammatory markers and insulin resistance index (HOMA-IR) in obese (Ob) adolescents and obese adolescents with metabolic syndrome (Ob-MS) compared to healthy controls (CO).Methods114 obese adolescents (60 Ob, age 13.6 ± 0.9 years, BMI 28.0 ± 2.2 kg/m², and 54 Ob-MS, age 13.8 ± 1.0 years, BMI 32.5 ± 4.8 kg/m²) and 37 CO (age 13.7 ± 0.8 years, BMI 22.8 ± 0.8 kg/m²) were studied. Anthropometrics, cardiac variables as well as fasting plasma concentrations of lipids, glucose, insulin, and adipocytokines (resistin, tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), C-reactive protein (CRP)) were measured. HOMA-IR was calculated, and the presence of MS was assessed.ResultsPlasma resistin was significantly higher in Ob-MS than in both Ob and CO and was correlated with anthropometric, cardiovascular, pro-inflammatory markers and several components of MS as was HOMA-IR in Ob and Ob-MS. With increasing the number of MS components, plasma resistin, pro-inflammatory markers, and HOMA-IR were also increased. Multiple regression models highlighted significant correlation between resistin and both HOMA-IR (r = 0.40, p < 0.05) and systolic blood pressure (r = 0.63, p < 0.01) in Ob-MS. Conclusion:These results support the hypothesis that there is an association between circulating resistin and childhood obesity-related inflammatory and cardiometabolic events.Key Words: Resistin, Metabolic syndrome, Insulin resistance, Childhood obesity, Inflammation     

Obesity in Older Adults and Associations with Cardiovascular Structure and Function

IntroductionBody mass index (BMI), despite being widely used as a marker of obesity, fails to fully capture cardiovascular risks as it is an insufficient biomarker of abdominal adiposity, unlike waist circumference (WC). We aimed to characterize associations between BMI and WC with cardiovascular structure and function in older adults.MethodsAmong an observational cohort study of a community of older adults, transthoracic echocardiography determined cardiovascular structure and function, while aerobic capacity was determined by peak oxygen uptake (VO₂) metrics. The cut-offs for obesity were 27.5 kg/m² for BMI, and >90 cm for males and >80 cm for females for WC.ResultsOf 970 older adults without cardiovascular disease (mean age 73 ± 4 years, 432 [44%] males), 124 (12.8%) were obese by BMI definition while 347 (35.7%) were obese by WC definition. Inter-definitional agreement was fair (Cohen''s κ = 0.345). Unlike the BMI definition, participants defined as obese by WC were more likely to be women (65% vs. 50%, p < 0.001), older (65 ± 11 vs. 63 ± 14 years, p = 0.007), and had lower handgrip strength (24 ± 0.6 vs. 26 ± 0.4 kg, p = 0.022). Across BMI categories, high WC was associated with more impaired myocardial relaxation (E/A), and VO₂ measurements (all p < 0.05). Among those with low BMI, high WC was associated with larger left atrial (LA) volumes (p = 0.003). WC, but not BMI, was independently associated with E/A (β = −0.114, SE −0.114 ± 0.024, p < 0.001) in regression analysis.ConclusionWC identified a higher prevalence of obesity, possibly related to central adiposity. Across BMI categories, WC identified more adverse measurements in E/A, aerobic capacity, and LA structure.Trial RegistrationClinicalTrials.gov Identifier: {"type":"clinical-trial","attrs":{"text":"NCT02791139","term_id":"NCT02791139"}}NCT02791139.     

BMI or BIA: Is Body Mass Index or Body Fat Mass a Better Predictor of Cardiovascular Risk in Overweight or Obese Children and Adolescents?

BackgroundBody fat (BF) percentiles for German children and adolescents have recently been published. This study aims to evaluate the association between bioelectrical impedance analysis(BIA)-derived BF and cardiovascular risk factors and to investigate whether BF is better suited than BMI in children and adolescents.MethodsData of 3,327 children and adolescents (BMI > 90th percentile) were included. Spearman''s correlation and receiver operating characteristics (ROCs) were applied determining the associations between BMI or BF and cardiovascular risk factors (hypertension, dyslipidemia, elevated liver enzymes, abnormal carbohydrate metabolism). Area under the curve (AUC) was calculated to predict cardiovascular risk factors.ResultsA significant association between both obesity indices and hypertension was present (all p < 0.0001), but the correlation with BMI was stronger (r = 0.22) compared to BF (r = 0.13). There were no differences between BMI and BF regarding their correlation with other cardiovascular risk factors. BF significantly predicted hypertension (AUC = 0.61), decreased HDL-cholesterol (AUC = 0.58), elevated LDL-cholesterol (AUC = 0.59), elevated liver enzymes (AUC = 0.61) (all p < 0.0001), and elevated triglycerides (AUC = 0.57, p < 0.05), but not abnormal carbohydrate metabolism (AUC = 0.54, p = 0.15). For the prediction of cardiovascular risk factors, no significant differences between BMI and BF were observed.ConclusionBIA-derived BF was not superior to BMI to predict cardiovascular risk factors in overweight or obese children and adolescents.Key Words: Bioelectrical impedance analysis, Body fat, Body mass index, Cardiovascular risk, Hypertension, Dyslipidemia, Children, Adolescent     

Validation of a Strict Obesity Definition Proposed for Asians to Predict Adverse Pregnancy Outcomes in Korean Pregnant Women

BackgroundPeople are generally considered overweight and obese if their body mass index (BMI) is above 25 kg/m² and 30.0 kg/m², respectively. The World Health Organization proposed stricter criteria for Asians (≥ 23 kg/m²: overweight, ≥ 25 kg/m²: obese). We aimed to verify whether this criteria could predict adverse pregnancy outcomes in Korean women.MethodsWe included 7,547 Korean women from 12 institutions enrolled between June 2016 and October 2018. Women with no pre-pregnancy BMI data, not Korean, or lost to follow-up were excluded, leaving 6,331. The subjects were categorized into underweight, normal, overweight, class I obesity, and class II/III obesity based on a pre-pregnancy BMI of < 18.5, 18.5–22.9, 23.0–24.9, 25.0–29.9, and ≥ 30.0 kg/m², respectively.ResultsOverall, 13.4%, 63.0%, 11.8%, 9.1%, and 2.6% of women were underweight, normal, and overweight and had class I obesity and class II/III obesity, respectively. In the multivariable analysis adjusted for maternal age, a higher BMI significantly increased the risk of preeclampsia, gestational diabetes, preterm delivery caused by maternal-fetal indications, cesarean section, large for gestational age, and neonatal intensive care unit admission.ConclusionAdverse pregnancy outcomes started to increase in those with a pre-pregnancy BMI ≥ 23.0 kg/m² after adjusting for maternal age. The modified obesity criteria could help predict adverse pregnancy outcomes in Koreans.     

Defining and Predicting Complete Remission of Type 2 Diabetes: A Short-Term Efficacy Study of Open Gastric Bypass

ObjectiveTo investigate the metabolic effects of open Roux-en Y gastric bypass (RYGB) on pancreatic endocrine reserve in overweight/obese Chinese patients with type 2 diabetes during postoperative year 1.MethodsRetrospective analysis comparing pre- and postoperative results of oral glucose tolerance tests (OGTT) with determinations of insulin and C-peptide, glycated hemoglobin (HbA1c), insulin resistance (HOMA-IR), and BMI at 1, 3, 6, and 12 months in 99 overweight patients (BMI 26.3 ± 4.0 kg/m²; 59 men) with type 2 diabetes at the General Hospital of Chengdu Military Region.Results79 patients (80%) achieved complete remission (maintaining random blood glucose levels < 11.1 mmol/l, fasting blood glucose levels < 7.0 mmol/l, 2-hour OGTT blood glucose levels < 11.1 mmol/l, and glycated hemoglobin < 6.5%). Nine cases (9%) were ‘improved’ (reduced medication or diet controlled blood sugar), and 11 cases did not meet either criterion (‘unchanged’). Patients in complete remission were younger and heavier, more often men, had significantly shorter history of diabetes (4.3 ± 3.8 years vs. 7.6 ± 3.8 years, p < 0.05), and exhibited significantly higher fasting and OGTT levels of C-peptide and insulin, and HOMA-IR than the other 2 groups (p < 0.05-0.01).ConclusionOpen gastric bypass achieved complete remission of type 2 diabetes in Chinese overweight/obese, heavier, younger, predominantly male patients with shorter duration of disease exhibiting greater pancreatic endocrine reserve.Key Words: Diabetes, Gastric bypass, Pancreatic function, Remission, Obesity     

Maternal Obesity and Pre-Pregnancy Folic Acid Supplementation

ObjectiveThe purpose of this nested cohort study was to compare the rate of pre-pregnancy supplementation in obese women with that of women with a normal BMI.MethodsPregnant women were enrolled at their convenience in a large university hospital. Weight and height were measured in the first trimester and BMI categorised.ResultsOf the 288 women, 35.1% were in the normal, 29.5% in the overweight and 35.4% in the obese BMI categories. Only 45.1% (n = 46) of the obese women took pre-pregnancy folic acid compared with 60.4% (n = 61) of women with a normal BMI (p < 0.03). The lower incidence of folic acid supplementation in obese women was associated with an unplanned pregnancy in 36.3% of women compared with 22.8% in the normal BMI category (p < 0.04).ConclusionsObese women should take folate supplements whether they are planning to conceive or not.Key Words: Maternal obesity, Pre-pregnancy folic acid, Body mass index, Unplanned pregnancy     

Longer Length of First Stay in Intermittent Residential Programmes Is Associated with Larger Weight Loss at 1 and 2 Years

Objective:To determine if length of first stay impacts on weight loss and cardiovascular fitness, at 1 and 2 years in severely obese patients enrolled in intermittent residential programs.Methods:In a retrospective follow-up study, we assessed weight loss and changes in cardiovascular fitness (VO₂ peak) at 1 and 2 years in 179 severely obese adults who participated in two intermittent residential programmes. Both programmes consisted of five stays at the Røros Rehabilitation Centre over a 2-year period, but programme A consisted of a much longer first stay compared with programme B (8 vs. 2 weeks).Results:Of 179 participants (BMI 44 ± 6 kg/m²), 162 completed 1-year and 117 2-year evaluation. Programme A led to significantly larger weight reduction (-20.7 ± 10.8 vs. −13.5 ± 8.1 kg and −16.0 ± 12.7 vs. −7.9 ± 11.2 kg, p < 0.0001) and improvement in VO₂ peak (7.8 vs. 3.6 ml/kg/min (p < 0.0001) and 5.6 vs. 2.5 ml/kg/min (p < 0.01)) at both 1 and 2 years, compared with programme B. Intention-to-treat analysis showed similar results.ConclusionA residential intermittent programme with a longer initial stay is associated with better weight loss and improvement in cardiovascular fitness at both 1 and 2 years. A longer follow-up is needed to clearly establish the sustainability of these programmes.Key Words: Cardiovascular fitness, Morbid obesity, Residential programs, Weight loss     

Association between Physical Activity,Sedentary Behaviors,Sleep, Diet,and Adiposity among Children and Adolescents in China

IntroductionPhysical activity (PA), sedentary behaviors (SB), sleep, and diet are related to adiposity among children and adolescents. However, there may be interactions between PA, SB, sleep, and diet, and these lifestyle behaviors may work together to affect body weight. The purpose of this study was to explore the impact of multiple lifestyle behaviors of PA, SB, sleep, and diet on childhood adiposity (body mass index z-score and overweight/obesity), and to investigate the effect of meeting multiple guidelines on adiposity among children and adolescents in China.MethodsCross-sectional results were based on 28,048 children aged 6–17 years from the China National Nutrition and Health Surveillance in 2010–2012. Information about PA, SB, and sleep was measured through interview-administered questionnaire. Dietary intake was assessed with food frequency questionnaire. The associations between multiple lifestyle behaviors and BMI z-score and overweight/obese were examined.ResultsThe prevalence of overweight/obesity in the participants was 19.2%. The average time of moderate-to-vigorous PA (MVPA), leisure SB, and sleep was 76.7 ± 45.5 min, 2.9 ± 1.4 h, and 8.5 ± 1.1 h per day, respectively. The China Dietary Guidelines Index for Youth (CDGI-Y) score was 62.6 ± 11.0. Sleep duration and diet score were negative associated with BMI z-score (both p < 0.001). MVPA and SB time were positive associated with BMI z-score (p = 0.041, 0.004). Meeting the SB, sleep, and diet guidelines had a lower BMI z-score (all p < 0.01) and lower odds of overweight/obesity (all p < 0.05). There were significant interactions between PA and diet. Compared with meeting no guidelines, those who met multiple guidelines had a lower risk of overweight/obesity (all p < 0.01). The more guidelines the participants met, the lower odds of overweight/obesity (p for trend <0.001).ConclusionsPA, SB, sleep, and diet are important behaviors associated with adiposity among children and adolescents. Attaining adequate amounts of appropriate multiple behaviors provided an additional benefit. It is important for children to meet recommended behavioral guidelines or recommendations. Interventions that aim to improve awareness of and compliance with these guidelines are needed in future.     

Development of a BMI-Assigned Stunkard Scale for the Evaluation of Body Image Perception Based on Data of the SOS Reference Study

IntroductionStunkard''s figure rating scale is a widely used tool to assess weight status and, more recently, body image perception in people with obesity. However, large population-based studies on Europeans linking this scale''s silhouettes with measured BMI values are lacking. Therefore, we used measured weight and height data from the Swedish Obese Subjects (SOS) reference cohort to assign a mean BMI to each of the 9 Stunkard Scale silhouettes and to define silhouette cutoff values for categorizing people with obesity and overweight.MethodsA total of 1,128 participants from the SOS reference cohort were included (54% females, BMI = 25.2 [ranging from 17.6 to 45.4] ±3.8 kg/m², and age = 50 [ranging from 36 to 62] ±7 years [means ± standard deviation]). Patients estimated their own body size by choosing a silhouette of the Stunkard Scale. A mean BMI, based on measured weight and height, was assigned to each male and female silhouette of the Stunkard Scale. Measured BMI values were compared with BMI values calculated by simple linear regression analysis. ROC analysis was used to test accuracy of discrimination and the Youden index to assess optimal cutoff.ResultsFigure ratings and BMI were strongly correlated in men, r (518) = 0.76, p < 0.001 and women, r (606) = 0.80, p < 0.001. Silhouette selection significantly predicted BMI values in men, β = 16.03, t (518) = 25.30, p < 0.001, and women, β = 12.06, t (606) = 32.98, p < 0.001, and explained a significant proportion of variance in BMI values in men, R² = 0.55, F (1, 518) = 639.98, p < 0.001, and women, R² = 0.64, F (1, 606) = 1,087.88, p < 0.001. ROC curve analyses resulted in an optimal cutoff value of 6 for identifying people with obesity and 5 for overweight.ConclusionStunkard''s figure rating scale can be used with confidence to assess weight status. Silhouette selection accurately classifies subjects as overweight or obese.     

Serum concentrations of adiponectin,leptin, resistin,ghrelin and insulin and their association with obesity indices in obese normo- and hypertensive patients – pilot study

Introduction

Hypertension often coexists with obesity. Adipokines, ghrelin and insulin play important roles in the pathogenesis of both diseases. The aim of this study was to compare adiponectin, leptin, resistin, insulin and ghrelin mean serum concentrations and insulin resistance (HOMA-IR) in normo- and hypertensive patients with obesity.

Material and methods

All included patients were divided on the following groups: non-diabetic hypertensive patients with class I obesity (group A, n = 21) and class II/III obesity (group B, n = 10), and normotensive obese (class I)patients (group C, n = 7). Correlations between obesity indices (body mass index [BMI], waist-to-hip ratio [WHR], waist circumference [WC]), HOMA-IR, and hormone and adipokine serum levels were also analyzed.

Results

Leptin level and HOMA-IR were significantly higher in group B compared to group C (9.74 ±3.88 ng/ml vs. 4.53 ±3.00 ng/ml; p < 0.02 and 3.30 ±1.59 vs. 1.65 ±0.41; p < 0.02, respectively). A negative correlation between WC and adiponectin level (R = –0.6275; p < 0.01) and a positive correlation between WC and insulin concentration (R = 0.5122; p< 0.05) as well as with HOMA-IR (R = 0.5228; p < 0.02) were found in group A. Negative correlations between BMI and ghrelin level (R = –0.7052; p < 0.05), WHR and adiponectin level (R = –0.6912; p < 0.05) and WHR and leptin level (R = –0.6728; p < 0.05) were observed in group B.

Conclusions

Insulin resistance and leptin may be important pathogenic factors in hypertensive patients with severe obesity. Indices of abdominal obesity (WC, WHR) correlate better than BMI with HOMA-IR, insulin, adiponectin and leptin serum levels in hypertensive obese patients.     

Fatty Acids,Obesity and Insulin Resistance

ObjectiveAlthough elevated free fatty acid (FFA) levels in obesity have been considered to be of importance for insulin resistance, a recent meta-analysis suggested normal FFA levels in obese subjects. We investigated fasting circulating FFA and glycerol levels in a large cohort of non-obese and obese subjects.MethodsSubjects recruited for a study on obesity genetics were investigated in the morning after an overnight fast (n = 3,888). Serum FFA (n = 3,306), plasma glycerol (n = 3,776), and insulin sensitivity index (HOMA-IR,n = 3,469) were determined. Obesity was defined as BMI ≥ 30 kg/m² and insulin resistance as HOMA-IR ≥ 2.21.ResultsIn obese subjects, circulating FFA and glycerol levels were higher than in non-obese individuals (by 26% and 47%, respectively; both p < 0.0001). Similar results were obtained if only men, women or medication-free subjects were investigated. Insulin resistance and type 2 diabetes were associated with a further minor increase in FFA/glycerol among obese subjects. When comparing insulin-sensitive non-obese with insulin-sensitive or -resistant obese individuals, FFA and glycerol were 21-29% and 43-49% higher in obese individuals, respectively.ConclusionCirculating FFA and glycerol levels are markedly elevated in obesity but only marginally influenced by insulin resistance and type 2 diabetes. Whether these differences persist during diurnal variations in circulating FFA/glycerol, remains to be established.Key Words: Lipid metabolism, Lipolysis, Glycerol, Adipose tissue     

Association between Sleeping Hours and Siesta and the Risk of Obesity: The SUN Mediterranean Cohort

ObjectivesOur aim was to investigate the association between sleeping hours at night and during the siesta and the incidence of obesity in a Mediterranean cohort.MethodsAfter a median of 6.5 years of follow-up, we included 10,532 or 9,470 participants without chronic disease or obesity at baseline for analyzing the association between the incidence of obesity and nocturnal sleep duration or having siesta. Sleeping hours and siesta were assessed at baseline. Weight was recorded at baseline and every 2 years during the follow-up. The outcome was the incidence of obesity during follow-up among participants with initial BMI <30 kg/m².ResultsDuring follow-up we observed 446 new cases of obesity in the analysis of nocturnal sleep duration. Sleeping less than 5 h at night was associated with a higher risk of becoming obese compared to sleeping between 7 and <8 h (HR 1.94; 95% CI 1.19-3.18; p for quadratic trend = 0.06) after adjusting for potential confounders. During follow-up, we observed 396 incident cases of obesity in the analysis of siesta. Those who took a siesta for 30 min/day had a 33% lower risk of becoming obese (HR 0.67; 95% CI 0.46-0.96; p for quadratic trend = 0.13) compared to those who did not take siesta.ConclusionOur results suggest that short nocturnal sleep duration could be a modifiable risk factor for obesity. It is possible that this association may be stronger among men and subjects who experienced previous weight gain. Additionally, siesta might be a novel and independent protective factor for obesity; however, confirmatory studies are needed.Key Words: Sleeping hours, Siesta, Obesity     

Brain-derived neurotrophic factor in relation to central obesity in children with sleep disordered breathing

IntroductionSleep disordered breathing (SDB) represents common comorbidities of childhood obesity leading to interrupted sleep and sleep deprivation. Sleep deprivation alters secretion of brain-derived neurotrophic factor (BDNF), which is an appetite regulator. However, little is known about the relation between BDNF and central obesity in children with SDB. The aim of the study was to evaluate BDNF level and anthropometric indices in relation to SDB in children with obesityMaterial and methodsA prospective case-control study was conducted on 30 children with obesity (BMI > 95^th percentile) and 30 healthy lean children (BMI 5^th-85^th percentile). Polysomnographic, anthropometric data and BDNF serum level were obtained from all included children. Serum level of BDNF and anthropometric indices of obesity were assessed in relation to SDB in children with obesity. Regression analysis was done to determine predictors for SDB in children with obesity.ResultsIn comparison to healthy controls, anthropometric indices of central obesity were significantly higher while BDNF was significantly lower in obese children, especially those with SDB. Respiratory disturbance index has a significant positive correlation with anthropometric indices of central obesity and a significant negative correlation with BDNF level. Central obesity and decreased BDNF were associated with 2-fold increased risk for SDB. Waist circumference/height ratio and neck circumference/height ratio have 89.5%, 75% sensitivity and 81.23%, 84.62% specificity at a cutoff point > 0.62, > 0.24 respectively for prediction of SDB in children with obesity.ConclusionsCentral obesity and decreased BDNF represent independent predictors for SDB in children with obesity. Anthropometric indices adjusted to height are a simple screening tool for SDB in obese children.     

Disparities in Obesity Prevalence in Iranian Adults: Cross-Sectional Study Using Data from the 2016 STEPS Survey

IntroductionThis paper outlines the prevalence, disparities, and social determinants of preobesity and obesity in Iranian adults.MethodsData on 28,321 adults who participated in the 2016 National Survey of the Risk Factors of Noncommunicable Diseases (STEPS) survey were analyzed. The body mass index (BMI) was calculated from physically measured height and weight. To assess the association between sociodemographic factors and the prevalence of preobesity and obesity, a χ² test and a logistic regression model were used. Socioeconomic inequality was quantified by a concentration index. Disparities in provincial mean BMI and concentration indices were shown on the map of Iran using geographic information system analysis.ResultsOverall, 60.3% of the participants were affected by preobesity or obesity. The preobesity prevalence was 39% in men and 35.2% in women. The obesity prevalence was 15.6% in men and 30.4% in women. The mean BMI for the country was 26.5. Higher ranges were observed across the northwestern and central territories. Female individuals in the age group 48–57 years who were married and lived in urban settings had an increased risk of being preobese or obese. The concentration index revealed a prorich inequality, with a greater magnitude among women.ConclusionThe findings suggest that policies aimed at reducing preobesity and obesity should remain a public health priority in Iran. However, a greater emphasis should be placed on the northwestern and central territories and on higher socioeconomic groups.     

Bone Response to High-Intensity Interval Training versus Moderate-Intensity Continuous Training in Adolescents with Obesity

IntroductionSince adolescents with obesity are prone to bone fragility during weight loss, the aim was to compare the impact of high-intensity interval training (HIIT) versus moderate-intensity continuous training (MICT) on bone density, geometry, and strength.MethodsSixty-one adolescents were randomly assigned to 2 cycling trainings (HIIT and MICT) and a control (CTR, without training) group. Anthropometry, dual-energy X-ray absorptiometry with hip structural analysis and the trabecular bone score (TBS) were assessed before and after the 16-week intervention.ResultsBody mass index (BMI) and fat mass (FM) percentage decreased at T1 versus T0 in both training groups (p < 0.001 for HIIT, p = 0.01 for MICT), though to a larger extent in HIIT (p < 0.05). Total body bone mineral density (BMD) and bone mineral content (BMC) increased in both training groups (p < 0.001), but to a greater extent in HIIT for BMC (p < 0.05). Lumbar spine BMD and BMC increased in both training groups (p < 0.001 for HIIT, p < 0.01 for MICT), with a time × group interaction between HIIT and CTR (p < 0.05) only. TBS increased in both training groups (p < 0.01 for HIIT, p < 0.05 for MICT). Hip BMD and BMC increased in both HIIT (p < 0.001 and p < 0.01) and MICT (p < 0.01 and p < 0.05). At the narrow neck (NN), endocortical diameter, width (p < 0.01), cross-sectional moment of inertia, and section modulus (Z) (p < 0.05) increased only in the HIIT group, such as BMD and Z (p < 0.05) at the intertrochanteric region (IT) and average cortical thickness (p < 0.001) and width (p < 0.05) at the femoral shaft. At the NN and IT, the buckling ratio decreased only in the HIIT group (p < 0.05), predicting higher resistance to fracture.ConclusionsIn addition to inducing greater BMI and FM percentage decreases in comparison to MICT, HIIT improves multisite bone density, geometry, and strength, which heighten the justification for HIIT as part of weight loss interventions in adolescents with obesity.     

Effect of BMI on the Thermogenic Response to Cold Exposure and Associated Changes in Metabolism and Browning Markers in Adult Humans

IntroductionBrown adipose tissue (BAT) serves to produce heat by nonshivering thermogenesis. Activation of BAT increases energy expenditure and is seen as a putative strategy to treat obesity. There are conflicting data on the capacity for cold-induced thermogenesis in individuals with higher BMI.MethodsTo investigate the effect of BMI on cold-induced stimulation of energy expenditure, changes in the metabolic profile, and the expression of browning markers in subcutaneous white adipose tissue (scWAT), healthy adults (N = 173, 50.9% females) with a median age of 26.0 (interquartile range [IQR]: 23.0; 28.0) years and a median body mass index (BMI) of 23.6 [IQR: 21.9; 26.6] kg/m² were exposed to short-term mild cold exposure (CE). Resting energy expenditure (REE) was measured by indirect calorimetry and blood sampling was conducted at baseline and after CE. In a subgroup of participants with obesity, subcutaneous abdominal fat biopsies were taken before and after CE.ResultsThe cold-induced median increase in REE was 74 (IQR: −28; 241) kcal/day (p < 0.001). This increase negatively correlated with BMI (p < 0.001). Participants with BMI 18.5–24.9 kg/m² displayed a significant median increase of 103 kcal/day (p < 0.001), participants with overweight or obesity were not able to increase REE (23, p = 0.468 or −30 kcal/day, p = 0.917, respectively). In participants with obesity, expression of cell death activator in scWAT after CE was upregulated in females (p = 0.034).ConclusionsPersons with overweight and obesity do not increase REE in response to CE, presumably reflecting lower BAT activity. Likewise, the metabolic response to cold is diminished in participants with elevated BMI.