Does metabolic health in overweight and obesity persist? - Individual variation and cardiovascular mortality over two decades

The impact of metabolic heterogeneity of obesity and transitions on cardiovascular disease incidence in Chinese middle-aged and elderly population: A nationwide prospective cohort study

BACKGROUND

Previous studies indicated that metabolic heterogeneity of obesity would affect the risk of cardiovascular disease (CVD). However, the alterations in CVD risk associated with transitions between various metabolic health statuses influenced by obesity status remain unclear.

METHODS

We utilized data from the China Health and Retirement Longitudinal Study (CHARLS), a longitudinal cohort study involving Chinese residents aged 45 years and older. Baseline data were collected in 2011-2012, with follow-up surveys conducted up to 2020. Participants in the study were categorized into four body mass index-metabolic phenotypes: metabolically healthy normal weight (MHNW), metabolically healthy overweight/obesity (MHOO), metabolically unhealthy normal weight (MUNW) and metabolically unhealthy overweight/obesity (MUOO). Transitions in these phenotypes over 4 years were analysed. Cox regression models were used to assess the associations of these phenotypes and their transitions with CVD incidence.

RESULTS

Among 7721 participants, 1353 (17.5%) developed CVD during the follow-up period. Both overweight/obese and metabolically unhealthy statuses were associated with increased CVD risk. The highest risk was observed in the MUOO group (hazard ratio [HR]: 1.74, 95% confidence interval [CI]: 1.50-2.09, p < 0.0001), followed by the MUNW (HR 1.35, 95% CI: 1.13-1.66, p < 0.001) and MHOO (HR: 1.29, 95% CI: 1.08-1.56, p = 0.002) groups compared to the MHNW group. The deteriorations of obesity and metabolic health status elevated the incidence of CVD, whereas improvements in these statuses reduced the risk of CVD. Additionally, alterations in metabolic health status conferred greater benefits in overweight/obese individuals compared to those with normal weight.

CONCLUSION

The study highlights the importance of maintaining and promoting metabolic health, particularly in overweight/obese individuals, to reduce CVD risk. Metabolic health status plays a more crucial role than obesity status in predicting CVD incidence.

Influence of body composition and cardiorespiratory fitness on plasma HSP72, norepinephrine, insulin, and glucose responses to an acute aerobic exercise bout performed in the fed state

Being overweight is already considered a metabolic risk factor, which can be overcome by increasing cardiorespiratory fitness (CRF). Acute exercise is known to induce changes in plasma hormones and heat shock proteins release. However, there is a lack of studies investigating the impact of body composition and CRF on these variables following acute aerobic exercise. To assess the influence of body composition and cardiorespiratory fitness on plasma heat shock protein 72 kDa (HSP72), norepinephrine (NE), insulin, and glucose responses to an acute aerobic exercise bout in the fed state. Twenty-four healthy male adults were recruited and allocated into three groups: overweight sedentary (n = 8), normal weight sedentary (n = 8), and normal weight active (n = 8). The volunteers performed an acute moderate exercise session on a treadmill at 70% of VO2 peak. Blood samples were drawn at baseline, immediately post-exercise, and at 1-h post-exercise. The exercise session did not induce changes in HSP72 nor NE but changes in glucose and insulin were affected by body mass index. Also, subjects with elevated CRF maintain reduced NE through exercise. At baseline, the overweight sedentary group showed elevated NE, insulin, and glucose; these last two impacting the HOMA-IR index. Thirty minutes of aerobic exercise at 70% VO2 peak, in the fed state, did not change the levels of plasma NE and HSP72. Elevated body composition seems to impact metabolic profile and increase sympathetic activity. Conversely, subjects with increased cardiorespiratory fitness seem to have attenuated sympathetic activity.

Associations Between Adult Triceps Skinfold Thickness and All-Cause, Cardiovascular and Cerebrovascular Mortality in NHANES 1999–2010: A Retrospective National Study

Background:

The association between triceps skinfold (TSF) thickness and mortality in previous studies was controversial. This study aimed to explore how TSF thickness affects all-cause, cardiovascular, and cerebrovascular mortality among the United States (U.S.) general population.

Methods

Our research included 25,954 adults in the National Health and Nutrition Examination Survey (NHANES) from 1999 to 2010. Participants were categorized by the baseline TSF quartiles [quartile 1 (Q1): &lt; 11.8, (Q2): 11.8–17.4, (Q3): 17.4–25, and (Q4): ≥25; unit: millimeter (mm)]. Cox regression models were used to assess the association of TSF with all-cause, cardiovascular, and cerebrovascular mortality. The association between mid-arm muscle circumference (MAMC) and mortality was also explored. Subgroup analyses were conducted to assess heterogeneity in different subgroups.

Results

The highest TSF group (Q4) had the lowest risk to experience all-cause (HR, 0.46; 95% CI, 0.38–0.59; P &lt; 0.001) and cardiovascular mortality (HR, 0.35; 95% CI, 0.23–0.54; P &lt; 0.001) than the lowest TSF group (Q1) after multivariate adjustment. However, there was no relationship between TSF quartiles and cerebrovascular mortality (HR, 0.98; 95%CI, 0.42–2.30; P = 0.97). The protective effects of TSF thickness on mortality still existed after adjusting for BMI and MAMC. For every 1 mm increase in TSF thickness, the risk of all-cause and cardiovascular death decreased by 4% (HR, 0.96; 95% CI, 0.95–0.97; P &lt; 0.001) and 6% (HR, 0.94; 95% CI, 0.93–0.96; P &lt; 0.001), respectively. In the stratified analysis, the relationships between TSF and mortality risk were generally similar across all subgroups.

Conclusions

Higher TSF thickness was associated with lower all-cause and cardiovascular mortality, independent of BMI and MAMC. Our study revealed that the TSF thickness may be a convenient and credible indicator to predict mortality, especially in those with severe cardiovascular diseases.

Obesity, Adipose Tissue, and Inflammation Answered in Questions

Background. Obesity is a global health problem of epidemic proportions, which is characterized by increased adipose tissue (AT) mass and significant repercussions in different body apparati and systems. AT is a special connective tissue, which contains several types of cells, in addition to adipocytes, and is a highly active endocrine and immune organ, which directly modulates many processes, including energy balance, metabolism, and inflammation. Summary. In this paper, the authors list and attempt to answer in a brief and simple way several questions regarding the complex relationships between obesity, adipose tissue, and inflammation, with the objective to provide an easy way to understand the main changes that occur in this pathological state. The questions are the following: Is adipose tissue only made up of adipocytes? Are adipocytes just a reservoir of free fatty acids? Do different types of fatty tissue exist? If so, which types? Can we further subcategorize the types of adipose tissue? Is it possible to form new adipocytes during adulthood? What is the role of inflammation? What is the role of macrophages? Are macrophages central mediators of obesity-induced adipose tissue inflammation and insulin resistance? What causes macrophage infiltration into adipose tissue? What is the role of hypoxia in AT alterations? Is there cross talk between adipocytes and immune cells? What other changes occur in AT in obesity? Does metabolically healthy obesity really exist? Is this a benign condition? Key messages. Obesity is a complex disease with numerous metabolic consequences, which are mainly the result of dysfunction that occurs in the adipose tissue of patients with this pathology. Understanding the pathophysiology of AT and the changes that occur in obesity would contribute to a better approach to patients with obesity, with the inherent medical implications that could result from this.

Association between being metabolically healthy/unhealthy and metabolic syndrome in Iranian adults

INTRODUCTION

The prevalence of metabolically healthy obesity (MHO) varies based on different criteria. We assessed the prevalence of MHO and metabolic unhealthiness based on body mass index (BMI) and their association with metabolic syndrome (MetS) in a nation-wide study.

METHODS

Data were taken from the STEPs 2016 study, from 18,459 Iranians aged ≥25 years. Demographic, metabolic, and anthropometric data were collected. Subjects were stratified by BMI, metabolic unhealthiness, and having MetS. The latter was defined based on National Cholesterol Education Program Adult Treatment Panel III 2004 (NCEP ATP III), was then assessed.

RESULTS

The prevalence of MHO and metabolic unhealthiness in obese subjects was 7.5% (about 3.6 million) and 18.3% (about 8.9 million), respectively. Most of the metabolic unhealthy individuals were female (53.5%) or urban residents (72.9%). Low physical activity was significantly and positively associated (Odds Ratio: 1.18, 95% CI: 1.04-1.35) with metabolic unhealthiness, while being a rural residence (0.83, 0.74-0.93), and having higher education (0.47, 0.39-0.58) significantly but negatively affected it. Dyslipidemia was the most frequent MetS component with a prevalence rate of 46.6% (42.1-51.1), 62.2% (60.8-63.6), 76.3% (75.1-77.5), and 83.4% (82.1-84.6) among underweight, normal weight, overweight and obese phenotypes, respectively.

CONCLUSION

BMI aside, an additional set of criteria such as metabolic markers should be taken into account to identify normal weight but metabolically unhealthy individuals. Given the highest prevalence of dyslipidemia among obese subjects, further interventions are required to raise public awareness, promote healthy lifestyles and establish lipid clinics.

Combined Effects of Metabolic Abnormalities and Obesity on Cardiovascular Diseases among Korean Postmenopausal Women

Combined effects of metabolic abnormalities, including metabolic syndrome and obesity, should be identified to screen postmenopausal women at risk of developing cardiovascular diseases. The purpose of this study was to identify the combined effects of metabolic abnormalities and obesity on cardiovascular diseases among postmenopausal Korean women (aged 40-83 years). Data of 5959 postmenopausal women from the Korean National Health and Nutrition Examination Survey (2015-2018) were secondarily analyzed. Using complex simple analysis procedures, logistic regression analysis was performed to identify the combined effect of metabolic abnormalities and obesity on cardiovascular diseases among postmenopausal Korean women. In combination, metabolic syndrome (more than three metabolic abnormalities) and obesity (overweight [≥23 kg/m² and <25 kg/m² in body mass index] and obese [>25 kg/m² in body mass index]) increased the likelihood of developing cardiovascular diseases but combining more than one metabolic abnormality and obesity did not. Combining metabolic syndrome and non-obesity (underweight and normal weight) increased the likelihood of the prevalence of cardiovascular diseases but combining more than one metabolic abnormality and non-obesity did not. Increased cardiovascular diseases in postmenopausal women may be more commonly associated with metabolic syndrome having multiple metabolic abnormalities, but not obesity. Thus, instead of simple weight control, early management of metabolic syndrome is recommended to prevent cardiovascular disease among postmenopausal Korean women.

Short-Term Changes in Metabolically Healthy Overweight/Obesity Status Impact the Susceptibility to Type 2 Diabetes in Chinese Adults

PURPOSE

Changes in transition from metabolically healthy overweight/obesity (MHO) to metabolically unhealthy overweight/obesity (MUO) are associated with the risk for cardiometabolic complications. This study aims to investigate the effects of short-term dynamic changes in body mass index (BMI) and metabolic status on the risk of type 2 diabetes (T2D) and to identify biological predictors for the MHO-to-MUO transition.

PATIENTS AND METHODS

A total of 4604 subjects from the REACTION study were included for a 3-year follow-up. Subjects were categorized based on their BMI and metabolic syndrome status. Overweight/obesity was defined as BMI ≥ 24 kg/m². Metabolically healthy was defined as having two or fewer of the metabolic syndrome components proposed by the Chinese Diabetes Society. Thus, subjects were divided into four groups: metabolically healthy normal weight (MHNW), MHO, metabolically unhealthy normal weight (MUNW), and MUO.

RESULTS

Compared with MHNW, MHO was not predisposed to an increased risk for T2D (OR 1.08, 95% CI 0.64-1.83, P = 0.762). However, a 3-year transition probability of 20.6% was identified for subjects who shifted from MHO to MUO; this conversion increased the risk of T2D by 3-fold (OR 3.04, 95% CI 1.21-7.68, P = 0.018). The fatty liver index independently predicted the MHO-to-MUO transition with an OR 3.14 (95% CI 1.56-7.46, P = 0.002) when comparing the fourth quartile to the first quartile.

CONCLUSION

This study reveals that metabolic changes affect the short-term susceptibility to T2D in the overweight/obese Chinese population, and the fatty liver index is an efficient clinical parameter for identifying those with a metabolic deterioration risk.

An Overview of the Role of Adipokines in Cardiometabolic Diseases

Obesity as an independent risk factor for cardiovascular diseases (CVDs) leads to an increase in morbidity, mortality, and a shortening of life span. The changes in heart structure and function as well as metabolic profile are caused by obese people, including those free of metabolic disorders. Obesity alters heart function structure and affects lipid and glucose metabolism, blood pressure, and increase inflammatory cytokines. Adipokines, specific cytokines of adipocytes, are involved in the progression of obesity and the associated co-morbidities. In the current study, we review the scientific evidence on the effects of obesity on CVDs, focusing on the changes in adipokines. Several adipokines have anti-inflammatory and cardioprotective effects comprising omentin, apelin, adiponectin, and secreted frizzled-related protein (Sfrp-5). Other adipokines have pro-inflammatory impacts on the cardiovascular system and obesity including leptin, tumor necrosis factor (TNF), retinol-binding protein4 (RBP-4), visfatin, resistin, and osteopontin. We found that obesity is associated with multiple CVDs, but can only occur in unhealthy metabolic patients. However, more studies should be designed to clarify the association between obesity, adipokine changes, and the occurrence of CVDs.

The Association between Excess Body Mass and Disturbances in Somatic Mineral Levels

BACKGROUND

Obesity and excess body weight are significant epidemiological issues, not only because they are costly to treat, but also because they are among the leading causes of death worldwide. In 2016, an estimated 40% of the global population was overweight, reflecting the importance of the issue. Obesity is linked to metabolism malfunction and concomitantly with altered mineral levels in the body. In this paper, we review alterations in somatic levels of iron, calcium, magnesium, copper, iodine, chromium, selenium, and zinc in relation to excess body mass.

METHODOLOGY

An electronic literature search was performed using PubMed. Our search covered original English research articles published over the past five years, culminating in 63 papers included for study.

RESULTS

The reviewed papers presented correlation between obesity and hypomagnesemia and hypozincemia. They also indicated that patients with excess body mass present increased body copper levels. Studies have similarly indicated that obesity appears to be associated with lower selenium levels in both blood and urine, which may be correlated with the decline and weakening of defenses against oxidative stress. It has been found that decreased level of chromium is connected with metabolic syndrome. Chromium supplementation influences body mass, but the effect of the supplementation depends on the chemical form of the chromium. It is hypothesized that obesity poses a risk of iodine deficiency and iodine absorption may be disrupted by increased fat intake in obese women. A range of studies have suggested that obesity is correlated with iron deficiency. On the other hand, some reports have indicated that excess body mass may coexist with iron excess. The relation between obesity and body iron level requires further investigation. Calcium signaling seems to be disturbed in obesity, due to the increased production of reactive oxygen species and low level of fast troponin isoform responsible for mediating calcium sensitivity of muscle relaxation. Correlation between excess body mass and calcium levels needs further research.

CONCLUSIONS

Excess body mass is associated with alterations in mineral levels in the body, in particular hypomagnesemia and decreased selenium (Se) and zinc (Zn) levels. Chromium (Cr) deficiency is associated with metabolic syndrome. Obese patients are at risk of iodine deficiency. Excess body mass is associated with elevated levels of copper (Cu). Data on the association between obesity and iron (Fe) levels are contradictory. Obesity coexists with disturbed calcium (Ca) signaling pathways. The association between obesity and body Ca levels has not been investigated in detail.

The effects of transitions in metabolic health and obesity status on incident cardiovascular disease: Insights from a general Chinese population

Background

Recent studies have investigated the association of transitions in metabolic health and obesity status over time with the risk of cardiovascular disease, focusing on the subgroup demonstrating metabolically healthy obesity. However, these studies have produced inconsistent results. This study evaluates the relation in a general Chinese population.

Methods

We conducted a prospective cohort study in a general population in Northeast China, with examinations of cardiovascular health from 2012–2015 and follow-up for incident cardiovascular disease until 2018. Cox proportional hazards and logistic regression models were used to investigate the association of baseline metabolic health and obesity status and transitions in those statuses with cardiovascular disease risk.

Results

A total of 7472 participants aged ≥35 years who were free of cardiovascular disease at baseline were included in this analysis. Over a median follow-up of 4.66 years, a total of 344 cardiovascular disease events occurred. Among the 3380 participants who were obese at baseline, 37.1% were metabolically healthy. Metabolically healthy obesity was associated with a 48% increased risk of cardiovascular disease (hazard ratio: 1.48; 95% confidence interval: 1.07–2.06) compared with the metabolically healthy non-obese group at baseline. Transition from metabolically healthy obesity to metabolically unhealthy obesity was associated with elevated cardiovascular disease risk with an odds ratio of 1.82 (95% confidence interval: 1.06–3.14) compared with metabolically healthy non-obesity throughout after adjustment. Even maintaining metabolically healthy obesity over time was associated with a higher risk of cardiovascular disease (odds ratio: 1.72; 95% confidence interval: 1.00–2.97).

Conclusions

Weight control and management of existing metabolic disorders should be prioritized in all obese population.

Transition of metabolic phenotypes and risk of subclinical atherosclerosis according to BMI: a prospective study

AIMS/HYPOTHESIS

The cardiometabolic risk associated with metabolically healthy obesity (MHO) remains the subject of debate. It is unclear whether MHO is a transient condition that affects subclinical atherosclerosis risk. In this study, we aimed to investigate the association of MHO and its transition over time with incident subclinical atherosclerosis.

METHODS

A prospective study was conducted with 6220 Chinese adults who were free of cardiovascular disease (CVD) at baseline. Obesity was defined as BMI ≥25.0 kg/m². Metabolic health was defined as an individual having fewer than two of the National Cholesterol Education Program Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (NCEP ATP III) criteria for components of the metabolic syndrome (excluding waist circumference). Subclinical atherosclerosis was measured by brachial-ankle pulse wave velocity, pulse pressure and albuminuria, separately or combined. Participants were cross-classified by BMI categories and by metabolic health status and its transition during follow-up. Inverse probability weighted logistic regression models were used to estimate ORs and 95% CIs for subclinical atherosclerosis.

RESULTS

The MHO phenotype accounted for 16.3% of the total population and 32.8% of the population with obesity at baseline. Baseline MHO was not significantly associated with incident subclinical atherosclerosis. During a follow-up period of 4.4 years, 46.8% of individuals with MHO developed a metabolically unhealthy status. Those with transient MHO had an increased risk of composite subclinical atherosclerosis compared with those in the metabolically healthy non-obesity reference group (OR 2.52 [95% CI 1.89, 3.36]). A transition from metabolically unhealthy to healthy status was shown to decrease the outcome risk. The relationship between BMI and subclinical atherosclerosis was partly mediated by BP and plasma glucose.

CONCLUSIONS/INTERPRETATION

MHO is not a stable condition and transient MHO conferred an increased risk of subclinical atherosclerosis, the early stage of CVD. Hence, individuals may benefit from early behavioural or medical management in order to avoid a deterioration of metabolic status and prevent atherosclerosis and CVD.

Associations between Macronutrient Intakes and Obesity/Metabolic Risk Phenotypes: Findings of the Korean National Health and Nutrition Examination Survey

Obesity is a risk factor for many health issues, as are metabolic abnormalities. However, few studies have addressed the associations between obesity/metabolic risk phenotypes and dietary macronutrient intakes (carbohydrate, protein, and fat). Therefore, this study examined the associations between macronutrient intakes and obesity/metabolic risk phenotypes in a Korean population. We used data from the Korean National Health and Nutrition Examination Survey, a cross-sectional survey of Korean civilians, conducted in 2014 and 2016, and data on a total of 7374 participants were analyzed. Macronutrient intakes were defined as the proportions of energy derived from carbohydrate, protein, and fat. Those exhibiting obesity/metabolic risk phenotypes (or not) were divided into four groups: normal weight without metabolic abnormalities; obese without metabolic abnormalities; normal weight with metabolic abnormalities; and obese with metabolic abnormalities. After adjusting for age, smoking status, alcohol consumption, extent of physical activity, household income, and daily fiber intake, no association was found between the proportions of carbohydrate, protein, or fat intakes and obesity/metabolic risk phenotypes except for a positive association between metabolically healthy but obese status and low protein intake in females. Further studies are required to evaluate the effects of macronutrient intakes on obesity/metabolic risk phenotypes and associated health outcomes.

Genes that make you fat, but keep you healthy

Obesity prevalence continues to rise worldwide, posing a substantial burden on people's health. However, up to 45% of obese individuals do not suffer from cardiometabolic complications, also called the metabolically healthy obese (MHO). Concurrently, up to 30% of normal-weight individuals demonstrate cardiometabolic risk factors that are generally observed in obese individuals, the metabolically obese normal weight (MONW). Besides lifestyle, environmental factors and demographic factors, innate biological mechanisms are known to contribute to the aetiology of the MHO and MONW phenotypes, as well. Experimental studies in animal models have shown that adipose tissue expandability, fat distribution, adipogenesis, adipose tissue vascularization, inflammation and fibrosis, and mitochondrial function are the main mechanisms that uncouple adiposity from its cardiometabolic comorbidities. We reviewed current genetic association studies to expand insights into the biology of MHO/MONW phenotypes. At least four genetic loci were identified through genome-wide association studies for body fat percentage (BF%) of which the BF%-increasing allele was associated with a protective effect on glycemic and lipid outcomes. For some, this association was mediated through favourable effects on body fat distribution. Other studies that characterized the genetic susceptibility of insulin resistance found that a higher susceptibility was associated with lower overall adiposity due to less fat accumulation at hips and legs, suggesting that an impaired capacity to store fat subcutaneously or a preferential storage in the intra-abdominal cavity may be metabolically harmful. Clearly, more work remains to be done in this field, first through gene discovery and subsequently through functional follow-up of identified genes.

Obesity and Aging in the Drosophila Model

Being overweight increases the risk of many metabolic disorders, but how it affects lifespan is not completely clear. Not all obese people become ill, and the exact mechanism that turns excessive fat storage into a health-threatening state remains unknown. Drosophila melanogaster has served as an excellent model for many diseases, including obesity, diabetes, and hyperglycemia-associated disorders, such as cardiomyopathy or nephropathy. Here, we review the connections between fat storage and aging in different types of fly obesity. Whereas obesity induced by high-fat or high-sugar diet is associated with hyperglycemia, cardiomyopathy, and in some cases, shortening of lifespan, there are also examples in which obesity correlates with longevity. Transgenic lines with downregulations of the insulin/insulin-like growth factor (IIS) and target of rapamycin (TOR) signaling pathways, flies reared under dietary restriction, and even certain longevity selection lines are obese, yet long-lived. The mechanisms that underlie the differential lifespans in distinct types of obesity remain to be elucidated, but fat turnover, inflammatory pathways, and dysregulations of glucose metabolism may play key roles. Altogether, Drosophila is an excellent model to study the physiology of adiposity in both health and disease.

Metabolically Healthy Obesity, Transition to Metabolic Syndrome, and Cardiovascular Risk

BACKGROUND

Debate over the cardiometabolic risk associated with metabolically healthy obesity (MHO) continues. Many studies have investigated this relationship by examining MHO at baseline with longitudinal follow-up, with inconsistent results.

OBJECTIVES

The authors hypothesized that MHO at baseline is transient and that transition to metabolic syndrome (MetS) and duration of MetS explains heterogeneity in incident cardiovascular disease (CVD) and all-cause mortality.

METHODS

Among 6,809 participants of the MESA (Multi-Ethnic Study of Atherosclerosis) the authors used Cox proportional hazards and logistic regression models to investigate the joint association of obesity (≥30 kg/m2) and MetS (International Diabetes Federation consensus definition) with CVD and mortality across a median of 12.2 years. We tested for interaction and conducted sensitivity analyses for a number of conditions.

RESULTS

Compared with metabolically healthy normal weight, baseline MHO was not significantly associated with incident CVD; however, almost one-half of those participants developed MetS during follow-up (unstable MHO). Those who had unstable MHO had increased odds of CVD (odds ratio [OR]: 1.60; 95% confidence interval [CI]: 1.14 to 2.25), compared with those with stable MHO or healthy normal weight. Dose response for duration of MetS was significantly and linearly associated with CVD (1 visit with MetS OR: 1.62; 95% CI: 1.27 to 2.07; 2 visits, OR: 1.92; 95% CI: 1.48 to 2.49; 3+ visits, OR: 2.33; 95% CI: 1.89 to 2.87; p value for trend <0.001) and MetS mediated approximately 62% (44% to 100%) of the relationship between obesity at any point during follow-up and CVD.

CONCLUSIONS

Metabolically healthy obesity is not a stable or reliable indicator of future risk for CVD. Weight loss and lifestyle management for CVD risk factors should be recommended to all individuals with obesity.

Skinfold thickness measurements and mortality in white males during 27.7 years of follow-up

INTRODUCTION

Obesity is a major risk factor for mortality from a range of causes. We investigated whether skinfold measurements were associated with mortality independently of variation in body mass index (BMI).

METHODS

A prospective analysis of mortality in 870 apparently healthy adult Caucasian men participating in an occupational health cohort was undertaken. At baseline, skinfold measurements were taken at biceps, triceps, iliac and subscapular sites. Derived measurements included the sum of all four skinfolds and subscapular to triceps, subscapular to iliac and BMI to iliac ratios. All-cause mortality was analysed by Cox proportional hazards modelling and death in specific mortality subcategories by competing risks analysis.

RESULTS

During a mean of 27.7 years follow up, there were 303 deaths (119 cancer, 101 arteriovascular, 40 infection, 43 other). In univariable analysis, BMI was associated with all-cause, cancer, arteriovascular and other mortality and subscapular skinfold with all-cause and arteriovascular mortality. On bivariable analysis, with inclusion of BMI, subscapular skinfold ceased to be a associated with mortality but iliac skinfold emerged as strongly, negatively associated with all-cause and arteriovascular mortality. In multivariable analysis, with inclusion of age, BMI, smoking, alcohol and exercise, iliac skinfold was negatively associated with all-cause (Hazard ratio HR 0.77, 95% confidence interval CI 0.66-0.90, p = 0.002), arteriovascular (HR 0.75, 95%CI 0.58,0.97, p = 0.02) and infection (HR 0.63, 95%CI 0.42,0.94, p = 0.02) death. Among obese participants (BMI ≥ 30 kg/m²), iliac skinfold of ≤9.7 mm was associated with a six-fold increase in all-cause mortality risk.

CONCLUSION

Low iliac skinfold thickness is an independent risk factor for all-cause mortality in adult white males with risk apparently concentrated among people who are obese.

A Prospective Study of Obesity, Metabolic Health, and Cancer Mortality

OBJECTIVE

This study examined whether metabolic health status is associated with risk of cancer mortality and whether this varies by body mass index (BMI) category.

METHODS

A prospective study of 22,514 participants from the Reasons for Geographic and Racial Differences in Stroke (REGARDS) cohort was performed. Metabolically unhealthy status was defined as having three or more of the following: (1) elevated fasting glucose, (2) high triglycerides, (3) dyslipidemia, (4) hypertension, and (5) elevated waist circumference. Participants were categorized into normal weight (BMI 18.5-24.9 kg/m² ), overweight (BMI 25.0-29.9 kg/m² ), and obesity (BMI ≥ 30 kg/m² ) groups. Cox proportional hazards regression was performed to estimate hazards ratios (HRs) and 95% confidence intervals (CIs) for cancer mortality during follow-up.

RESULTS

Among participants with normal weight, participants who were metabolically unhealthy had an increased risk of cancer mortality (HR: 1.65; 95% CI: 1.20-2.26) compared with metabolically healthy participants. The overall mortality risk for participants who were metabolically unhealthy and had normal weight was stronger for obesity-related cancers (HR: 2.40; 95% CI: 1.17-4.91). Compared with participants with normal weight, those who were metabolically healthy and overweight were at a reduced risk of any cancer mortality (adjusted HR: 0.79; 95% CI: 0.63-0.99).

CONCLUSIONS

There was an increased risk of overall and obesity-related cancer mortality among metabolically unhealthy participants with normal weight.

Obesity and Metabolic Unhealthiness Have Different Effects on Colorectal Neoplasms

CONTEXT

Obesity and insulin resistance are risk factors for colorectal neoplasms (CRN), but data regarding metabolic status, obesity, and CRN are lacking.

OBJECTIVE

To investigate the relationship between metabolic status, obesity, and CRN in Koreans who underwent colonoscopy.

DESIGN

Retrospective, cross-sectional.

PARTICIPANTS

Subjects were divided based on metabolic and obesity criteria, as follows: metabolically healthy nonobese (MHNO), metabolically healthy obese (MHO), metabolically unhealthy nonobese (MUNO), and metabolically unhealthy obese (MUO).

MAIN OUTCOME MEASURES

Multiple regression was used to identify CRN and advanced CRN risk factors, with the MHNO group as reference.

RESULTS

A total of 10,235 subjects was included, as follows: 5096 MHNO, 1538 MHO, 1746 MUNO, and 1855 MUO. Of these, 3297 had CRN (32.2%), and 434 (4.2%) had advanced CRN. Number of subjects with CRN in each group were: MHNO 25.8%, MHO 33.9%, MUNO 38.9%, and MUO 42.0% (P for trend < 0.001). Risk of CRN was increased in the MHO [odds ratio (OR) 1.239, 95% confidence interval (CI) 1.082 to 1.418, P = 0.002], the MUNO (OR 1.233, 95% CI 1.086 to 1.400, P = 0.001), and the MUO groups (OR 1.510, 95% CI 1.338 to 1.706, P < 0.001), whereas risk of advanced CRN was increased in the MUNO (OR 1.587, 95% CI 1.222 to 2.062, P = 0.001) and the MUO groups (OR 1.456, 95% CI 1.116 to 1.900, P = 0.006).

CONCLUSIONS

Obesity increased CRN risk with metabolically unhealthy status adding risk. For advanced CRN, metabolically unhealthy status increased the risk but obesity did not.