Obesity can predispose people to develop high pressures inside their lung blood vessels, a condition called pulmonary hypertension, Pulmonary hypertension in turn, can lead to shortness of breath and other health complications such as heart failure. In this study, we seek to identify individuals at risk for the development of high pressures inside lung vessels based on BMI and dyspnea grade 1.~Participants will be screened by echocardiography to estimate pulmonary pressures. Potential participants will undergo invasive cardiopulmonary exercise testing with hemodynamic monitoring, in order to identify individuals with abnormal pulmonary vascular function either at rest or during exercise. Patients who have undergone clinically-indicated cardiopulmonary exercise testing and meet inclusion/exclusion criteria will also be recruited. Those with abnormal pulmonary vascular function will be randomized to receive Metformin or placebo for a total of 3 months under an IND exemption. The primary outcomes include the effect on pulmonary vascular function at rest and during exercise. Secondary outcomes include change in pulmonary artery endothelial cell phenotypes.
This study will investigate if metformin can help people with obesity and high pressures inside their lung blood vessels. Metformin is approved by the U.S. Food and Drug Administration (FDA) to treat diabetes, but metformin is not approved by the FDA to treat pulmonary hypertension.~This study will examine whether Metformin will improve the high pressure inside lung blood vessels in people who are obese. The study will help understand the effect of metformin on pressures inside lung blood vessels.