THE EFFECT OF WEIGHT LOSS AND EXERCISE ON CARDIOVASCULAR STRUCTURE AND FUNCTION IN CLASS II AND III OBESE WOMEN

Introduction: Obesity is a public health concern in its association with various comorbidities, especially cardiovascular disease. Negative structural and functional changes of the left ventricle are associated with obesity and research is conflicting as to the effect of diet-induced and diet plus exercise-induced weight loss in Class II and III obese adults. Purpose: The purpose of this study was to examine effect of diet-induced or diet plus exercise-induced weight loss on cardiac structure and function in Class II and III obese women. Methods: 24 healthy, sedentary, obese women (BMI: 35.0 to 45 kg/m2; Age: 45.4 + 6.9yrs.) underwent a 12-week diet and exercise intervention: caloric restriction alone (DIET), caloric restriction plus aerobic training (DIET+AT), and caloric restriction plus resistance training (DIET+RT). Subjects reported to UPMC Presbyterian Hospital to undergo Cardiac MRI to measure left ventricular mass (LVM), myocardial fibrosis (Ve), end diastolic volume (EDV), end systolic volume (ESV), and ejection fraction (EF). Results: 18 out of 24 subjects completed the intervention. 16 out of 24 completed 12 week Cardiac MRI at UPMC Presbyterian. Body weight significantly decreased across all treatment groups (~4.5kg lost, p=0.001). Subjects in the DIET group had significantly greater reduction in LVM (-7.2 ± 3.9g) than the DIET+AT (2.3 ± 4.7g) and DIET+RT (-0.2 ± 3.5g) groups (p=0.007). Subjects in the DIET+RT group had a significantly higher Ve score at 12 weeks (27.9 ± 1.5%) than subjects in the DIET+AT (26.5 ± 1.4%) and DIET (24.0 ± 0.8%) groups (p=0.010). There were no significant changes in EDV, ESV, or EF at 12 weeks between groups (p>0.159). Conclusions: In conclusion, only LVM in the DIET group and Ve in the DIET+RT showed statistical changes from baseline. Further investigations into the effect of weight loss and exercise on cardiac structure and function in Class II and III obese adults are warranted to expand upon the results of this investigation