Advisory Committee Chair
Emily Levitan
Advisory Committee Members
Bertha Hidalgo
Suzanne Judd
Document Type
Thesis
Date of Award
2022
Degree Name by School
Master of Science (MS) School of Public Health
Abstract
A major obstacle to the advancement of our understanding of the metabolically healthy obesity (MHO) phenotype is the inconsistent definition of metabolic health and obesity among studies. A harmonized definition of MHO in adults has been proposed based on the diagnosis of obesity (BMI > 30 k/m2) and meeting the cardio-metabolic criteria for triglycerides, high-density lipoprotein (HDL) cholesterol, systolic blood pressure (SBP), diastolic blood pressure (DBP), no antihypertensive treatment, fasting blood glucose, and no drug treatment with glucose-lowering agents. In addition, waist circumference can be associated with increased disease risk when WC is >94 cm in men and >80 cm in women. Individuals with MHO have been shown to have a lower risk of cardiovascular disease (CVD) and mortality compared to those with metabolically unhealthy obesity (MUHO). MUHO has been defined as being obese with the presence of metabolic risk factors. However, a person can transition from MHO to metabolically unhealthy obesity (MUHO), potentially developing a greater risk for CVD. Data were collected as part of the Reasons for Geographic and Racial Differences in Stroke (REGARDS) study. The association between MHO (compared to MUHO and compared to other healthy and unhealthy phenotypes) and coronary heart disease (CHD) was tested iii using Cox proportional hazards models. To define MHO and other phenotypes, we included WC as one of the criteria. The analysis included 20,142 participants who were free of CHD at baseline. Among those in the obese group, MHO represented 0.8% (N=61). BMI (35.5 + 4.9) and waist circumference (WC) (107.5 + 12.9) were highest in the MUHO group. Black adults represented 53.0% of the obese category (N=4,054). The MUHO group showed a 2.7 times higher risk (hazard ratio [HR]: 2.66; 95% CI: 2.08-3.40) with metabolically healthy without obesity (MHWO) as a reference. Primary analyses showed that the unadjusted model for the MHO group showed no difference: HR: 1.002 [95% CI: 0.25-4.09] with MHWO as the reference group. When adjusted for covariates of interest, the MHO group showed a 21% increased risk, with a HR of 1.21 [95% CI: 0.30, 4.93]. By the second in-home visit, approximately 10 years after study entry, only 16% (N=4) of participants who were MHO at baseline remained MHO. Our results indicate that further analysis is needed when describing the various metabolic phenotypes and utilizing WC as a method of categorizing people as unhealthy or healthy. WC, in addition to BMI, could help determine fat distribution, which, in turn, helps to better define “obesity” and those who are truly healthy.
Recommended Citation
Aaron, Kiara N., "The Association Between Metabolically Healthy Obesity and Coronary Heart Disease Among Regards Study Participants" (2022). All ETDs from UAB. 116.
https://digitalcommons.library.uab.edu/etd-collection/116
