PCR: Polymerase Chain Reaction, BMI: Body Mass Index, %SpO2: Percent Saturation of Peripheral Oxygen, HTN: Hypertension, COPD: Chronic Obstructive Pulmonary Disease, ACE Hx: History of Angiotensin-Converting Enzyme inhibitor use, ARB Hx: History of Angiotensin II Receptor Blocker use, N: Number. This evidence concerns the gene ACE and chronic obstructive pulmonary disease.