Discordant risk: Overweight and cardiometabolic risk in Chinese adults

Objective:

Recent US work identified “metabolically healthy overweight” and “metabolically at risk normal weight” individuals. Less is known for modernizing countries with recent increased obesity.

Design and Methods:

Fasting blood samples, anthropometry and blood pressure from 8,233 adults aged 18‐98 in the 2009 nationwide China Health and Nutrition Survey, were used to determine prevalence of overweight (Asian cut point, BMI ≥23 kg/m²) and five risk factors (prediabetes/diabetes (hemoglobin A1c ≥5.7%) inflammation (high‐sensitivity C‐reactive protein (hsCRP) ≥3 mg/l), prehypertension/hypertension (Systolic blood pressure/diastolic blood pressure≥130/85 mm Hg), high triglycerides (≥150 mg/dl), low high‐density lipoprotein cholesterol (<40 (men)/ <50 mg/dl (women)). Sex‐stratified, logistic, and multinomial logistic regression models estimated concurrent obesity and cardiometabolic risk, with and without abdominal obesity, adjusting for age, smoking, alcohol consumption, physical activity, urbanicity, and income.

Results:

Irrespective of urbanicity, 78.3% of the sample had ≥1 elevated cardiometabolic risk factor (normal weight: 33.2% had ≥1 elevated risk factor; overweight: 5.7% had none). At the age of 18‐30 years, 47.4% had no elevated risk factors, which dropped to 6% by the age 70, largely due to age‐related increase in hypertension risk (18‐30 years: 11%; >70 years: 73%). Abdominal obesity was highly predictive of metabolic risk, irrespective of overweight (e.g., “metabolically at risk overweight” relative to “metabolically healthy normal weight” (men: relative risk ratio (RRR) = 39.06; 95% confidence interval (CI): 23.47, 65.00; women: RRR = 22.26; 95% CI: 17.49, 28.33)).

Conclusion:

A large proportion of Chinese adults have metabolic abnormalities. High hypertension risk with age, underlies the low prevalence of metabolically healthy overweight. Screening for cardiometabolic‐related outcomes dependent upon overweight will likely miss a large portion of the Chinese at risk population.     

Prevalence of Metabolically Discordant Phenotypes in a Mediterranean Population—the Imap Study

ObjectiveTo study the prevalence and correlates of body size phenotypes in an adult Spanish population.MethodsWe undertook a cross-sectional analysis in a random sample of 2,270 individuals. We defined six body size phenotypes based on body mass index category (normal-weight, 18.5 to 24.9 kg/m²; overweight, 25 to 29.9 kg/m²; obese, ≥30.0 kg/m²) and the presence of ≤1 (meta- bolically healthy) or ≥2 (metabolically abnormal) cardio- metabolic abnormalities: metabolically healthy normal- weight (MHNW), metabolically abnormal normal-weight (MANW), metabolically healthy overweight (MHOW), metabolically abnormal overweight (MAOW), metaboli- cally healthy obese (MHO), and metabolically abnormal obese (MAO). We considered four cardiometabolic abnormalities: systolic and/or diastolic blood pressure ≥130/85 mm Hg, triglycerides ≥150 mg/dL, high-density-lipopro- tein cholesterol levels <40/<50 mg/dL in men/women, and elevated glucose (fasting plasma glucose ≥100 mg/dL or previous diabetes).ResultsSubmitted for publication October 30, 2012 Accepted for publication April 1, 2013From the ¹The prevalence of the MHO, MHOW, and MANW phenotypes was 2.2, 13.9, and 7.9%, respectively. Whereas 9.6% of obese and 32.6% of overweight individuals were metabolically healthy, 21.3% of the normal- weight subjects were metabolically abnormal. A multivariate regression model (adjusted for age, sex, and waist circumference) showed that age >40 years, male sex, and higher waist circumference were independently associated with the metabolically abnormal phenotype MANW, whereas younger age, female sex, and lower waist circumference were independently associated with the metabolically healthy phenotypes.ConclusionThe prevalence of MHO in our population is low and is more common in women and younger people. In contrast, a high proportion of normal-weight individuals (mainly over 40 years of age) in our population show cardiometabolic abnormalities. (Endocr Pract. 2013;19:758-768)     

Body Fat Distribution and Inflammation Among Obese Older Adults With and Without Metabolic Syndrome

The protective mechanisms by which some obese individuals escape the detrimental metabolic consequences of obesity are not understood. This study examined differences in body fat distribution and adipocytokines in obese older persons with and without metabolic syndrome. Additionally, we examined whether adipocytokines mediate the association between body fat distribution and metabolic syndrome. Data were from 729 obese men and women (BMI ≥30 kg/m²), aged 70–79 participating in the Health, Aging and Body Composition (Health ABC) study. Thirty‐one percent of these obese men and women did not have metabolic syndrome. Obese persons with metabolic syndrome had significantly more abdominal visceral fat (men: P = 0.04; women: P < 0.01) and less thigh subcutaneous fat (men: P = 0.09; women: P < 0.01) than those without metabolic syndrome. Additionally, those with metabolic syndrome had significantly higher levels of interleukin‐6 (IL‐6), tumor necrosis factor‐α (TNF‐α), and plasminogen activator inhibitor‐1 (PAI‐1) than individuals without metabolic syndrome. Per standard deviation higher in visceral fat, the likelihood of metabolic syndrome significantly increased in women (odds ratio (OR): 2.16, 95% confidence interval (CI): 1.59–2.94). In contrast, the likelihood of metabolic syndrome decreased in both men (OR: 0.56, 95% CI: 0.39–0.80) and women (OR: 0.49, 95% CI: 0.34–0.69) with each standard deviation higher in thigh subcutaneous fat. These associations were partly mediated by adipocytokines; the association between thigh subcutaneous fat and metabolic syndrome was no longer significant in men. In summary, metabolically healthy obese older persons had a more favorable fat distribution, characterized by lower visceral fat and greater thigh subcutaneous fat and a more favorable inflammatory profile compared to their metabolically unhealthy obese counterparts.     

Associations of visceral and liver fat with the metabolic syndrome across the spectrum of obesity: the AGES-Reykjavik study

Visceral adipose tissue (VAT) is a key pathogenic fat depot in the metabolic syndrome (MetS), but liver fat (LF) may also play an important role. We evaluated associations of VAT and LF with MetS in normal weight, overweight, and obese men and women (BMI <25, 25-29.9, and ≥30 kg/m2, respectively). This analysis included 2,495 participants from the Age, Gene/Environment Susceptibility (AGES)-Reykjavik study with computed tomography measurements for VAT and LF. MetS was defined by ≥3 of the following: larger abdominal circumference, hypertension, elevated triglyceride (TG), low high-density lipoprotein (HDL), impaired fasting glucose (IFG), and microalbuminuria. We estimated the odds of MetS per 1-s.d. increase in VAT and LF, adjusting for key covariates. VAT was associated with an increased odds of MetS in normal weight, overweight, and obese women (odds ratios (OR) = 2.78, 1.63, and 1.43, respectively; all P < 0.01) that diminished in magnitude with increasing BMI (VAT × BMI class interaction P < 0.001). In men, VAT was related to MetS only among the overweight (OR = 1.69, P < 0.01). LF was associated with MetS in the overweight and obese groups in women (OR = 1.38 and 1.45; both P < 0.001) and in men (OR = 1.38, P = 0.01; and OR = 1.27, P = 0.10), but not in the normal weight groups. These BMI-specific relationships persisted when both fat depots were included in the model. VAT and LF were associated with MetS independently of each other, and these relationships were modified by BMI class such that, VAT was the more important depot at lower levels of obesity and LF at higher levels. Importantly, fatty liver may be a novel metabolic risk factor in overweight and obese individuals.     

Incident cardiovascular disease events in metabolically benign obese individuals

Nearly one-third of obese individuals are classified as metabolically benign; however whether this subgroup is at a lower risk of cardiovascular disease (CVD) is unclear. Using pooled data from the Atherosclerosis Risk in Communities and Cardiovascular Health Studies, we assessed incident CVD (coronary heart disease and stroke) using three definitions of the metabolically benign phenotype: (i) the ATP-III metabolic syndrome definition (≤2 of the ATP-III components, excluding abdominal obesity (ii) the expanded ATP-III definition (≤1 of: any ATP-III components, insulin resistance (IR), or systemic inflammation), and (iii) the IR-based definition (sex-specific lowest quartile of the HOMA(IR) distribution). The sample included 6,106 normal weight, 7,115 overweight, and 4,323 obese participants. Among obese, 27.0%, 18.1%, and 20.4% were metabolically benign by the three definitions, respectively. The CVD incidence rates (mean follow-up 11.8 years) were 7.1, 5.8, and 8.4 per 1,000 person-years in metabolically benign obese via the three definitions, respectively, compared to 14.3, 13.8, and 13.3 in at-risk obese, and 7.5, 6.7, and 8.2 in metabolically benign normal weight participants. Multivariable-adjusted hazard ratios of incident CVD in metabolically benign obese compared to their at-risk obese counterparts were 0.59 (95% CI 0.47-0.73), 0.52 (0.39-0.68), and 0.71 (0.57-0.90), respectively; and 1.24 (0.99-1.57), 1.16 (0.86-1.56), and 1.28 (1.01-1.62) compared to metabolically benign normal weight individuals. Only 28.7% of obese participants classified as metabolically benign by at least one definition were "metabolically benign" by all three definitions. Despite similar CVD risk estimates, the three definitions identified different subgroups of the obese population, perhaps suggesting distinct etiologies.     

Metabolic Abnormalities Are Common among South American Hispanics Subjects with Normal Weight or Excess Body Weight: The CRONICAS Cohort Study

Objective

We aimed to characterize metabolic status by body mass index (BMI) status.

Methods

The CRONICAS longitudinal study was performed in an age-and-sex stratified random sample of participants aged 35 years or older in four Peruvian settings: Lima (Peru’s capital, costal urban, highly urbanized), urban and rural Puno (both high-altitude), and Tumbes (costal semirural). Data from the baseline study, conducted in 2010, was used. Individuals were classified by BMI as normal weight (18.5–24.9 kg/m²), overweight (25.0–29.9 kg/m²), and obese (≥30 kg/m²), and as metabolically healthy (0–1 metabolic abnormality) or metabolically unhealthy (≥2 abnormalities). Abnormalities included individual components of the metabolic syndrome, high-sensitivity C-reactive protein, and insulin resistance.

Results

A total of 3088 (age 55.6±12.6 years, 51.3% females) had all measurements. Of these, 890 (28.8%), 1361 (44.1%) and 837 (27.1%) were normal weight, overweight and obese, respectively. Overall, 19.0% of normal weight in contrast to 54.9% of overweight and 77.7% of obese individuals had ≥3 risk factors (p<0.001). Among normal weight individuals, 43.1% were metabolically unhealthy, and age ≥65 years, female, and highest socioeconomic groups were more likely to have this pattern. In contrast, only 16.4% of overweight and 3.9% of obese individuals were metabolically healthy and, compared to Lima, the rural and urban sites in Puno were more likely to have a metabolically healthier profile.

Conclusions

Most Peruvians with overweight and obesity have additional risk factors for cardiovascular disease, as well as a majority of those with a healthy weight. Prevention programs aimed at individuals with a normal BMI, and those who are overweight and obese, are urgently needed, such as screening for elevated fasting cholesterol and glucose.     

Obesity and Lowered Cognitive Performance in a Canadian First Nations Population

The association between obesity, other cardiovascular risk factors, and cognitive function in a Canadian First Nations population was investigated using a cross‐sectional design. Eligible individuals were aged ≥18 years, without a history of stroke, nonpregnant, with First Nations status, and who had undergone cognitive function assessment by the Clock Drawing Test (CDT) and Trail Making Test Parts A and B. Parts A and B were combined into an Executive Function Score (TMT‐exec). Hypertension, a previous history of cardiovascular disease, dyslipidemia, metabolic syndrome, insulin resistance, and the presence and duration of diabetes were examined in addition to obesity. In the case of TMT‐exec only, obese individuals were at an approximately fourfold increased risk for lowered cognitive performance compared to those who were not obese in multivariable models (odds ratio (OR): 3.77, 95% confidence interval (CI): 1.46–9.72) whereas there was no effect for overweight individuals compared to those with a normal weight in unadjusted analysis. Those having an increased waist circumference also had 5 times the risk compared to those without an increased waist circumference (OR: 5.41, 95% CI: 1.83–15.99). Adjusted for age, sex, and insulin resistance, individuals having the metabolic syndrome were at an approximately fourfold increased risk compared to those without the metabolic syndrome (OR: 3.67, 95% CI: 1.34–10.07). No other cardiovascular risk factors were associated. Obesity and metabolic syndrome were associated with lowered cognitive performance. These results highlight the importance of studying the health effects of obesity beyond traditional disease endpoints, even in a relatively youthful population.     

Body composition determinants of metabolic phenotypes of obesity in nonobese and obese postmenopausal women

Objective : Although obesity is typically associated with increased cardiovascular risk, a subset of obese individuals display a normal metabolic profile (“metabolically healthy obese,” MHO) and conversely, a subset of nonobese subjects present with obesity‐associated cardiometabolic abnormalities (“metabolically obese nonobese,” MONO). The aim of this cross‐sectional study was to identify the most important body composition determinants of metabolic phenotypes of obesity in nonobese and obese healthy postmenopausal women. Design and Methods : We studied a total of 150 postmenopausal women (age 54 ± 7 years, mean ± 1 SD). Based on a cardiometabolic risk score, nonobese (body mass index [BMI] ≤ 27) and obese women (BMI > 27) were classified into “metabolically healthy” and “unhealthy” phenotypes. Total and regional body composition was assessed with dual‐energy X‐ray absorptiometry (DXA). Results : In both obese and nonobese groups, the “unhealthy” phenotypes were characterized by frequent bodyweight fluctuations, higher biochemical markers of insulin resistance, hepatic steatosis and inflammation, and higher anthropometric and DXA‐derived indices of central adiposity, compared with “healthy” phenotypes. Indices of total adiposity, peripheral fat distribution and lean body mass were not significantly different between “healthy” and “unhealthy” phenotypes. Despite having increased fat mass, MHO women exhibited comparable cardiometabolic parameters with healthy nonobese, and better glucose and lipid levels than MONO. Two DXA‐derived indices, trunk‐to‐legs and abdominal‐to‐gluteofemoral fat ratio were the major independent determinants of the “unhealthy” phenotypes in our cohort. Conclusions : The “metabolically obese phenotype” is associated with bodyweight variability, multiple cardiometabolic abnormalities and an excess of central relative to peripheral fat in postmenopausal women. DXA‐derived centrality ratios can discriminate effectively between metabolic subtypes of obesity in menopause.     

A metabolically healthy obese phenotype in hispanic participants in the IRAS family study

Objective: Some obese individuals appear to be protected from developing type 2 diabetes mellitus and cardiovascular disease (CVD). This has led to characterizing body size phenotypes based on cardiometabolic risk factors specifically as obese or overweight, and as metabolically healthy (MH) or metabolically abnormal (MA) based upon blood pressure, lipids, glucose homeostasis, and inflammatory parameters. The aim of this study was to measure the prevalence of and describe fat distribution across these phenotypes in a minority population. Design and Methods: Hispanic participants (N = 1054) in the IRAS Family Study were categorized into different body size phenotypes. Computed tomography (CT) abdominal scans were evaluated for measures of nonalcoholic fatty liver disease (NAFLD) and abdominal fat distribution. Statistical models adjusting for familial relationships were estimated. Results: Seventy percent (70%) of the Hispanic cohort was overweight (32%) or obese (38%). Forty‐one percent (n = 138) of overweight participants and 19% (n = 74) of obese participants met criteria for MH. Adjusted analyses showed the MH phenotype was associated with lower visceral adipose tissue (VAT) and higher liver density (indicating lower fat content) in obese participants (p = 0.0005 and p = 0.0002, respectively), and lower VAT but not liver density in overweight participants (p = 0.008 and p = 0.162, respectively) compared to their MA counterparts. Odds of NAFLD were reduced in MH obese (OR = 0.34, p = 0.0007) compared to MA obese. VAT did not differ between MH obese or overweight and normal weight groups. Conclusions: These findings suggest that lower levels of visceral and liver fat, despite overall increased total body fat, may be a defining feature of MH obesity in Hispanic Americans.     

Are Sexual Dissatisfaction and Sexual Abuse Associated with Obesity? A Population‐Based Study

Objective: To investigate whether there is any association between obesity and sexual satisfaction and sexual abuse in a normal population. Research Methods and Procedures: A representative sample of 2810 subjects from a population study was interviewed about sexual satisfaction, sexual abuse, and life satisfaction. The answers from normal weight, overweight, and obese participants were compared. Univariate and multivariate analyses were performed. Results: Data were presented separately for two age groups, 18 to 49 and 50 to 74 years, and gender. The older group of obese men reported a greater decrease of sexual desire compared with 5 years prior than normal weight men [odds ratios (OR), 2.44; 95% confidence interval (CI), 1.4 to 4.3]. The older group of overweight men reported involuntary participation in sexual activities more often than normal weight men (OR, 2.06; 95% CI, 1.1 to 3.8). Although older overweight and obese women were diagnosed with a lingering disease (defined as >1 month) more often than normal weight women (overweight: OR, 2.41; 95% CI, 1.3 to 4.4; obese: OR, 4.45; 95% CI, 1.7 to 11.5), there was no difference between BMI groups in satisfaction with physical health. Discussion: Overweight and obese groups seem to be heterogeneous with respect to sexual satisfaction and experiences of sexual abuse. No significant differences were detected between BMI groups, which does not exclude the possibility of significant differences between BMI groups among patients seeking medical attention.     

Combined Impact of Cardiorespiratory Fitness and Visceral Adiposity on Metabolic Syndrome in Overweight and Obese Adults in Korea

Background

Obesity, especially visceral obesity, is known to be an important correlate for cardiovascular disease and increased mortality. On the other hand, high cardiorespiratory fitness is suggested to be an effective contributor for reducing this risk. This study was conducted to determine the combined impact of cardiorespiratory fitness and visceral adiposity, otherwise known as fitness and fatness, on metabolic syndrome in overweight and obese adults.

Methods

A total of 232 overweight and obese individuals were grouped into four subtypes according to their fitness level. This was measured by recovery heart rate from a step test in addition to visceral adiposity defined as the visceral adipose tissue area to subcutaneous adipose tissue area ratio (VAT/SAT ratio). Associations of fitness and visceral fatness were analyzed in comparison with the prevalence of metabolic syndrome.

Results

The high visceral fat and low fitness group had the highest prevalence of metabolic syndrome [Odds Ratio (OR) 5.02; 95% Confidence Interval (CI) 1.85–13.61] compared with the reference group, which was the low visceral adiposity and high fitness group, after adjustments for confounding factors. Viscerally lean but unfit subjects were associated with a higher prevalence of metabolic syndrome than more viscerally obese but fit subjects (OR 3.42; 95% CI 1.27–9.19, and OR 2.70; 95% CI 1.01–7.25, respectively).

Conclusions

Our study shows that visceral obesity and fitness levels are cumulatively associated with a higher prevalence of metabolic syndrome in healthy overweight and obese adults. This suggests that cardiorespiratory fitness is a significant modifier in the relation of visceral adiposity to adverse metabolic outcomes in overweight and obese individuals.     

Racial/Ethnic Differences in Weight Perception

The objective of this research was to estimate the prevalence of weight misperception among adults using the most recent nationally representative data, according to measured weight category and to assess the relationship between weight misperception and race/ethnicity. Height and weight were measured as part of the 1999–2006 National Health and Nutrition Examination Survey. The study sample consisted of 17,270 adults aged ≥20 years. BMI was categorized as underweight (BMI < 18.5), healthy weight (18.5 ≤ BMI < 25), overweight (25 ≤ BMI < 30), and obese (BMI ≥ 30). Subjects reported self‐perception of weight status. Among study subjects, 31.7% of healthy weight adults, 38.1% of overweight adults, and 8.1% of obese adults incorrectly perceived their weight category. Among obese men, the odds of weight misperception were higher for non‐Hispanic blacks (odds ratio (OR) = 3.0; 95% confidence interval (CI) = 2.0–4.5) compared to non‐Hispanic whites and for persons with less than a high school education (OR = 2.1; 95% CI = 1.3–2.1), compared to those with some college education. Among obese women, the odds of weight misperception were higher for non‐Hispanic blacks (OR = 3.4; 95% CI = 1.4, 3.1) and Mexican Americans (OR = 1.9; 95% CI = 1.2, 3.2) compared to non‐Hispanic whites and for persons with less than high school education compared to those with some college education (OR = 5.5; 95% CI = 3.3–9.3). Weight misperception is highly prevalent in the US population, and more frequent in racial/ethnic minorities, males, and in persons with lower educational levels. Addressing the issue of weight misperception may help address the problem of obesity in the United States by increasing awareness of healthy weight levels, which may subsequently have an impact on weight‐related behavior change.     

The association between self‐reported sleep quality and overweight in a Chinese population

Objective:

Sleep quality and obesity are associated with type 2 diabetes, hypertension, and metabolic syndrome. However, there is limited research on the association between sleep quality and obesity, and thus the aim of this study is to investigate this relationship in a Chinese population.

Design and Methods:

Subjects were recruited from the Prevention Health Center of National Cheng Kung University Hospital. Anthropometric data and metabolic parameters were measured. Being overweight or obese was defined according to the recommendations of the Department of Health in Taiwan. Sleep quality was assessed using the Pittsburgh Sleep Quality Index (PSQI).

Results:

Of the total 2,803 subjects, 1,059 were classified as normal weight, 1,127 were overweight, and 617 were obese. The global PSQI score were 6.30 ± 2.56, 6.61 ± 2.96, and 7.02 ± 2.95 in subjects who were normal weight, overweight, and obese, respectively (test for trend, P < 0.001). Of the variables tested in the multivariate linear regression model, female gender, being overweight, obesity, sleep duration, and alcohol drinking were significantly associated with global PSQI scores, and in the multivariate logistic regression model, female gender, being overweight, obesity, and sleep duration were independent predictors of poor sleepers after controlling for age, gender, BMI or different weight statuses, sleep duration, alcohol drinking, smoking, habitual exercise, hypertension, newly diagnosed diabetes, total cholesterol, high‐density lipoprotein, triglyceride, estimated glomerular filtration rate, and alanine aminotransferase.

Conclusions:

In conclusion, female gender, being overweight, obesity, and sleep duration were associated with poor sleep quality independent of cardiometabolic risk factors. In clinical practice, subjects who are obese, or even only overweight, should be evaluated for the presence of sleep disturbance.     

Correlation among soluble receptors for advanced glycation end-products,soluble vascular adhesion protein-1/semicarbazide-sensitive amine oxidase (sVAP-1) and cardiometabolic risk markers in apparently healthy adolescents: a cross-sectional study

In non-diabetics, low levels of soluble receptor for advanced glycations end products (sRAGE) associate with an increased risk of development of diabetes, cardiovascular afflictions, or death. The majority of studies in non-diabetics report an inverse relationship between measures of obesity, cardiometabolic risk factors and sRAGE and/or endogenous secretory RAGE (esRAGE) levels. To elucidate whether this inconsistency is related to the metabolically healthy obese phenotype, or a different impact of the risk factors in presence and absence of obesity, we analyzed data from 2206 apparently healthy adolescents (51 % girls) aged 15-to-19 years. The association of sRAGE levels with soluble vascular adhesion protein-1/semicarbazide sensitive amine oxidase (sVAP-1/SSAO) was also investigated. Centrally obese, including metabolically healthy, adolescents present significantly lower sRAGE and esRAGE, but not sVAP-1, levels in comparison with their lean counterparts. An increasing number of cardiometabolic risk factors did not associate with significant changes in sRAGE, esRAGE or sVAP-1 levels either in lean or in obese subjects. In multivariate analyses, WHtR, hsCRP, markers of glucose homeostasis, renal function, adiponectin, and sVAP-1 associated significantly with sRAGE and esRAGE. SVAP-1 correlated significantly with glycemia, adiponectin, hsCRP, and sRAGE. Thus, in adolescents, a decline in sRAGE and esRAGE precedes the development of metabolic syndrome. When combined, standard and non-standard cardiometabolic risk factors explain only minor proportion in a variability of sRAGE and esRAGE (8 %–11 %); or sVAP-1 (12 %–20 %). Elucidation of pathogenetic mechanisms underlying early decline in sRAGE and esRAGE levels in obese adolescents and their clinical impact with regard to future cardiometabolic health requires further studies.     

Evaluation of Bioelectrical Impedance Analysis for Identifying Overweight Individuals at Increased Cardiometabolic Risk: A Cross-Sectional Study

Objective

To investigate whether bioelectrical impedance analysis could be used to identify overweight individuals at increased cardiometabolic risk, defined as the presence of metabolic syndrome and/or diabetes.

Design and Methods

Cross-sectional study of a Scottish population including 1210 women and 788 men. The diagnostic performance of thresholds of percentage body fat measured by bioelectrical impedance analysis to identify people at increased cardiometabolic risk was assessed using receiver-operating characteristic curves. Odds ratios for increased cardiometabolic risk in body mass index categories associated with values above compared to below sex-specific percentage body fat thresholds with optimal diagnostic performance were calculated using multivariable logistic regression analyses. The validity of bioelectrical impedance analysis to measure percentage body fat in this population was tested by examining agreement between bioelectrical impedance analysis and dual-energy X-ray absorptiometry in a subgroup of individuals.

Results

Participants were aged 16-91 years and the optimal bioelectrical impedance analysis cut-points for percentage body fat for identifying people at increased cardiometabolic risk were 25.9% for men and 37.1% for women. Stratifying by these percentage body fat cut-points, the prevalence of increased cardiometabolic risk was 48% and 38% above the threshold and 24% and 19% below these thresholds for men and women, respectively. By comparison, stratifying by percentage body fat category had little impact on identifying increased cardiometabolic risk in normal weight and obese individuals. Fully adjusted odds ratios of being at increased cardiometabolic risk among overweight people with percentage body fat ≥25.9/37.1% compared with percentage body fat <25.9/37.1% as a reference were 1.93 (95% confidence interval: 1.20–3.10) for men and 1.79 (1.10–2.92) for women.

Conclusion

Percentage body fat measured using bioelectrical impedance analysis above a sex-specific threshold could be used in overweight people to identify individuals at increased cardiometabolic risk, who could benefit from risk factor management.     

The Changing Body Mass–Mortality Association in the United States: Evidence of Sex-Specific Cohort Trends from Three National Health and Nutrition Examination Surveys

The association between body mass index (BMI) categories and mortality remains uncertain. Using three National Health and Nutrition Examination Surveys covering the 1971–2006 period for cohorts born between 1896 and 1968, this study estimates separately for men and women models for year-of-birth (cohort) and year-of-observation (period) trends in how age-specific mortality rates differ across BMI categories. Among women, relative to the normal weight (BMI 18.5–24.9 kg/m²), there are increasing trends in mortality rates for the overweight (BMI 25–29.9) or obese (BMI ≥ 30). Among men, mortality rates relative to the normal weight decrease for the overweight, do not change for the moderately obese (BMI 30–34.9), and increase for the severely obese (BMI ≥ 35). Period and cohort trends are similar, but the cohort trends are more consistent. In the latest cohorts, compared with the normal weight, mortality rates are 50 percent lower for overweight men, not different for moderately obese men, and 100–200 percent higher for severely obese men and for overweight or obese women. For U.S. cohorts born after the 1920s, a lower overweight than normal weight mortality is confined to men. I speculate on possible reasons why the mortality association with overweight and obesity varies by sex and cohort.     

Effect of obesity on short- and long-term mortality postcoronary revascularization: a meta-analysis

Objective: Overweight and obesity are often assumed to be risk factors for postprocedural mortality in patients with coronary artery disease (CAD). However, recent studies have described an “obesity paradox”—a neutral or beneficial association between obesity and mortality postcoronary revascularization. We reviewed the effect of overweight and obesity systematically on short‐ and long‐term all‐cause mortality post‐coronary artery bypass grafting (CABG) and post‐percutaneous coronary intervention (PCI). Methods: We searched the Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, Scopus, and Web of Science to identify cohort, case control, and randomized controlled studies evaluating the effect of obesity on in‐hospital/short‐term (within 30 days) and long‐term (up to 5 years) mortality. Full‐text, published articles reporting all‐cause mortality between individuals with and without elevated BMI were included. Two reviewers independently assessed studies for inclusion and performed data extraction. Results: Twenty‐two cohort publications were identified, reporting results in ten post‐PCI and twelve post‐CABG populations. Compared to individuals with non‐elevated BMI levels, obese patients undergoing PCI had lower short‐ (odds ratio (OR) 0.63; 95% confidence interval (CI) 0.54–0.73) and long‐term mortality (OR 0.65; 95% CI 0.51–0.83). Post‐CABG, obese patients had lower short‐term (OR 0.63; 95% CI 0.56–0.71) and similar long‐term (OR 0.88; 95% CI 0.60–1.29) mortality risk compared to normal weight individuals. Results were similar in overweight patients for both procedures. Conclusions: Compared to non‐obese individuals, overweight and obese patients have similar or lower short‐ and long‐term mortality rates postcoronary revascularization. Further research is needed to confirm the validity of these findings and delineate potential underlying mechanisms.     

Prevalence and determinants of obesity in children in public schools of Sintra, Portugal

Objective: To assess the prevalence of and the factors related to overweight and obesity in a sample of children from the region of Sintra, Portugal. Methods and Procedures: Cross‐sectional study, stratified for freguesia with random selection of schools. Height, weight, triceps skinfold, upper arm and waist circumferences were measured, and overweight/obesity defined according to international criteria. Breast‐feeding, number of daily meals and parents' height and weight data were also collected. Results: One thousand two hundred and twenty‐five children aged 6–10 years were assessed. Overall prevalence of overweight and obesity was 35.6% (23% overweight and 12.6% obesity). Overweight or obese children had higher triceps skinfold, upper arm circumference, arm muscle area, and waist circumference than their normal weight counterparts (P < 0.001). On multivariate analysis, relatively to a child without obese progenitors, a child with one obese progenitor had an obesity risk multiplied by 2.78 (95% confidence interval (CI): 1.76–4.38), while a child with two obese progenitors had a risk multiplied by 6.47 (95% CI: 5.59–16.19). Conversely, being picky was significantly related with a smaller risk of obesity: for boys, odds ratio (OR) = 0.15 (95% CI: 0.04–0.63); for girls, OR = 0.19 (95% CI: 0.06–0.64). Finally, no relationships were found between obesity, birth weight, birth height or breast‐feeding. Discussion: Prevalence of overweight and obesity are elevated among children of the Sintra region in Portugal compared to most other regions of Europe. The relationship with the parents' nutritional state stresses the need to target families for preventing obesity.     

Genetic Effects on Longitudinal Changes from Healthy to Adverse Weight and Metabolic Status — The HUNT Study

IntroductionThe complexity of obesity and onset and susceptibility of cardio-metabolic disorders are still poorly understood and is addressed here through studies of genetic influence on weight gain and increased metabolic risk longitudinally.Subjects/MethodsTwenty seven previously identified obesity, eating disorder or metabolic risk susceptibility SNPs were tested for association with weight or metabolically related traits longitudinally in 3999 adults participating both in the HUNT2 (1995–97) and HUNT3 (2006–08) surveys. Regression analyses were performed with changes from normal weight to overweight/obesity or from metabolically healthy to adverse developments with regards to blood pressure, glucose, HDL cholesterol, triglycerides or metabolic syndrome as outcomes. Additionally, a sub-sample of 1380 adolescents was included for testing association of nine SNPs with longitudinal weight gain into young adulthood.ResultsThe most substantial effect on BMI-based weight gain from normal to overweight/obesity in adults was observed for the DRD2 variant (rs6277)(OR: 0.79, 95% CI: 0.69–0.90, P = 3.9x10^-4, adj. P = 0.015). DRD2 was not associated with BMI on a cross-sectional level. In the adolescent sample, FTO (rs1121980) was associated with change to overweight at adulthood in the combined male-female sample (OR: 1.27, 95% CI: 1.09–1.49, P = 3.0x10^-3, adj. P = 0.019) and in females (OR: 1.53, 95% CI: 1.23–1.91, P = 1.8x10^-4, adj. P = 0.003). When testing for association to longitudinal adverse developments with regard to blood pressure, blood lipids and glucose, only rs964184 (ZNF259/APOA5) was significantly associated to unfavourable triglyceride changes (OR: 1.66, 95% CI: 1.36–2.03, P = 5.7x10^-7, adj. P = 0.001). Pleiotropic effects on metabolic traits, however, were observed for several genetic loci cross-sectionally, ZNF259/APOA5, LPL and GRB14 being the most important.Conclusions DRD2 exhibits effects on weight gain from normal weight to overweight/obesity in adults, while, FTO is associated to weight gain from adolescence to young adulthood. Unhealthy longitudinal triglyceride development is strongly affected by ZNF259/APOA. Our main finding, linking the DRD2 variant directly to the longitudinal weight gain observed, has not previously been identified. It suggests a genetic pre-disposition involving the dopaminergic signalling pathways known to play a role in food reward and satiety linked mechanisms.     

Defining Metabolically Healthy Obesity: Role of Dietary and Lifestyle Factors

Background

There is a current lack of consensus on defining metabolically healthy obesity (MHO). Limited data on dietary and lifestyle factors and MHO exist. The aim of this study is to compare the prevalence, dietary factors and lifestyle behaviours of metabolically healthy and unhealthy obese and non-obese subjects according to different metabolic health criteria.

Method

Cross-sectional sample of 1,008 men and 1,039 women aged 45-74 years participated in the study. Participants were classified as obese (BMI ≥30kg/m²) and non-obese (BMI <30kg/m²). Metabolic health status was defined using five existing MH definitions based on a range of cardiometabolic abnormalities. Dietary composition and quality, food pyramid servings, physical activity, alcohol and smoking behaviours were examined.

Results

The prevalence of MHO varied considerably between definitions (2.2% to 11.9%), was higher among females and generally increased with age. Agreement between MHO classifications was poor. Among the obese, prevalence of MH was 6.8% to 36.6%. Among the non-obese, prevalence of metabolically unhealthy subjects was 21.8% to 87%. Calorie intake, dietary macronutrient composition, physical activity, alcohol and smoking behaviours were similar between the metabolically healthy and unhealthy regardless of BMI. Greater compliance with food pyramid recommendations and higher dietary quality were positively associated with metabolic health in obese (OR 1.45-1.53 unadjusted model) and non-obese subjects (OR 1.37-1.39 unadjusted model), respectively. Physical activity was associated with MHO defined by insulin resistance (OR 1.87, 95% CI 1.19-2.92, p = 0.006).

Conclusion

A standard MHO definition is required. Moderate and high levels of physical activity and compliance with food pyramid recommendations increase the likelihood of MHO. Stratification of obese individuals based on their metabolic health phenotype may be important in ascertaining the appropriate therapeutic or intervention strategy.