Association of metabolically healthy obesity in young adulthood with myocardial structure and function

Association of Anthropometric Indices With Midlife Cardiovascular Risk in Young Individuals Without Obesity and Traditional Risk Factors

BACKGROUND

The aim of this study was to assess how early-adulthood body mass index (BMI) and waist circumference (WC) relate to long-term cardiovascular structure, function, and prognosis in individuals without obesity and with low cardiovascular risk factor (CVRF) burden.

METHODS AND RESULTS

A total of 2024 participants aged 18 to 30 from the CARDIA (Coronary Artery Risk Development in Young Adults) study, without obesity and with low CVRFs defined as the absence of cardiovascular disease (CVD), diabetes, hypertension, current smoking, and dyslipidemia were included. A CVRF-optimal subgroup was also defined, with blood pressure<120/80 mm Hg, fasting glucose <100 mg/dL, total cholesterol <200, low-density lipoprotein cholesterol <130, and women with high-density lipoprotein cholesterol ≥50 mg/dL. Coronary artery calcification, carotid intima-media thickness, left ventricular mass, left ventricular ejection fraction, longitudinal peak systolic strain, and diastolic function were assessed in midlife. Cox regression was used to calculate hazard ratios of BMI and WC for all-cause death and CVD events. Logistic regression was used to estimate odds ratios for subclinical CVD. Over 33.9 years (median follow-up), 5.2% (n=105) died, and 2.6% (n=52) had CVD events. Each 1-SD BMI increase was associated with 27% (95% CI, 1.10-1.47), 24% (1.08-1.43), 42% (1.20-1.68), 28% (1.05-1.57), 51% (1.20-1.90), and 49% (1.10-2.02) higher odds of coronary artery calcification presence, increased carotid intima-media thickness, left ventricular hypertrophy, reduced left ventricular ejection fraction, low longitudinal peak systolic strain, and diastolic dysfunction, respectively, in the CVRF-low group. Generally, similar associations were found for WC and in the CVRF-optimal subgroup. No significant associations between BMI and WC with CVD and death were found.

CONCLUSIONS

Elevations in BMI and WC among young low-risk individuals, even within the nonobesity range, are associated with midlife cardiovascular health.

Characteristics of the epicardial adipose tissue measured by low-dose chest computed tomography according to the metabolic health/obesity status

BACKGROUND

Epicardial adipose tissue (EAT) is associated with the development of cardiovascular disease and long-term survival. This study aimed to assess the characteristics of EAT according to the metabolic health and obesity status using low-dose chest computed tomography (CT).

METHODS

A total of 1074 asymptomatic adults who underwent a medical health check-up were enrolled. Subjects were categorized into the following four groups according to the metabolic health and obesity status: metabolically healthy non-obese (MHNO); metabolically unhealthy non-obese (MUNO); metabolically healthy obese (MHO); and metabolically unhealthy obese (MUO). EAT on low-dose chest CT was measured by using automatic, quantitative measurement software.

RESULTS

MUO showed the highest EAT volume and lowest EAT radiodensity in comparison with MHNO (p < 0.001). The MUNO (n = 70), MHO (n = 259), and MUO (n = 231) groups had increased EAT volume (β [95 % CI], 37.65 [23.11,52.18], 56.79 [47.56,66.02], 84.85 [74.59,95.11] respectively, all p < 0.001), decreased EAT radiodensity (β [95 % CI], - 3.22 [- 4.59,- 1.85], - 4.48 [- 5.30,- 3.66], - 6.03 [- 6.90,- 5.16] respectively, all p < 0.001) in comparison with the MHNO (n = 514) group by using multivariable linear regression models.

CONCLUSIONS

Both metabolic abnormalities and obesity were closely associated with EAT characteristics. Characteristics of EAT are similar in MHO and MUNO. This finding suggests that MHO is not a favorable condition in terms of cardiac health, as assessed by the characteristics of EAT. The combination of obesity and metabolically unhealthy status has a synergistic adverse effect on EAT. Measurement of EAT could be a useful imaging biomarker for evaluation of an individual's metabolic health/obesity status.

Cardiometabolic characteristics of people with metabolically healthy and unhealthy obesity

There is considerable heterogeneity in the cardiometabolic abnormalities associated with obesity. We evaluated multi-organ system metabolic function in 20 adults with metabolically healthy obesity (MHO; normal fasting glucose and triglycerides, oral glucose tolerance, intrahepatic triglyceride content, and whole-body insulin sensitivity), 20 adults with metabolically unhealthy obesity (MUO; prediabetes, hepatic steatosis, and whole-body insulin resistance), and 15 adults who were metabolically healthy lean. Compared with MUO, people with MHO had (1) altered skeletal muscle biology (decreased ceramide content and increased expression of genes involved in BCAA catabolism and mitochondrial structure/function); (2) altered adipose tissue biology (decreased expression of genes involved in inflammation and extracellular matrix remodeling and increased expression of genes involved in lipogenesis); (3) lower 24-h plasma glucose, insulin, non-esterified fatty acids, and triglycerides; (4) higher plasma adiponectin and lower plasma PAI-1 concentrations; and (5) decreased oxidative stress. These findings provide a framework of potential mechanisms responsible for MHO and the metabolic heterogeneity of obesity. This study was registered at ClinicalTrials.gov (NCT02706262).

Metabolic health's central role in chronic kidney disease progression: a 20-year study of obesity-metabolic phenotype transitions

This study investigates the risk of chronic kidney disease (CKD) across four metabolic phenotypes: Metabolically Healthy-No Obesity (MH-NO), Metabolically Unhealthy-No obesity (MU-NO), Metabolically Healthy-Obesity (MH-O), and Metabolically Unhealthy-Obesity (MU-O). Data from the Tehran Lipid and Glucose Study, collected from 1999 to 2020, were used to categorize participants based on a BMI ≥ 30 kg/m2 and metabolic health status, defined by the presence of three or four of the following components: high blood pressure, elevated triglycerides, low high-density lipoprotein, and high fasting blood sugar. CKD, characterized by a glomerular filtration rate < 60 ml/min/1.72 m2. The hazard ratio (HR) of CKD risk was evaluated using Cox proportional hazard models. The study included 8731 participants, with an average age of 39.93 years, and identified 734 incidents of CKD. After adjusting for covariates, the MU-O group demonstrated the highest risk of CKD progression (HR 1.42-1.87), followed by the MU-NO group (HR 1.33-1.67), and the MH-O group (HR 1.18-1.54). Persistent MU-NO and MU-O posed the highest CKD risk compared to transitional states, highlighting the significance of exposure during early adulthood. These findings emphasize the independent contributions of excess weight and metabolic health, along with its components, to CKD risk. Therefore, preventive strategies should prioritize interventions during early-adulthood.