UC Irvine

ABSTRACT OF THE THESIS

Clinical Predictors of Metabolic Syndrome

By

Samir T. Mukherjee

Master of Science in Environmental Health Sciences

University of California, Irvine, 2017

Professor Bongkyoo Choi, Chair

Metabolic syndrome refers to the co-occurrence of several cardiovascular risk factors, including insulin resistance, dyslipidemia, obesity, and hypertension. It is an escalating public health challenge with an estimated worldwide prevalence of 25%. Metabolic syndrome is also a powerful prognostic indicator for atherosclerotic cardiovascular disease, which remains the leading cause of morbidity and mortality within the United States.

Two simple clinical measures, resting heart rate (RHR) and heart rate reserve (HRR), have been shown to be associated with metabolic syndrome in the general population. Currently, however, there is a paucity of evidence in the scientific literature describing this association within the adult working population. Given the significant economic impact of cardiovascular disease on the occupational work force, the purpose of this study was to evaluate RHR and HRR as cost-effective screening metrics for the detection of metabolic syndrome.

Data from the biomarker project of the Midlife in the United States (MIDUS II) cross-sectional survey were analyzed using a combination of binary logistic regression, independent samples t-testing, prevalence ratio analysis, and generation of receiver operating characteristics (ROC) in order to elucidate the strength of the proposed relationships. All statistical analysis was performed using JMP v13.0.0. The results suggested that both RHR and HRR are reliable predictors of metabolic syndrome; however, RHR generally had a stronger association within the younger study population regardless of gender. HRR was a stronger predictor among the older subset of participants, and demonstrated a marginally better discriminative ability throughout the sample population. The results for both predictor variables were significant at the p < 0.05 level. The utility of RHR and HRR as screening tools for metabolic syndrome, however, was lower than expected, as the area under the ROC curve was less than the desired cut-off level of 0.7.