Adiposity and Airway Inflammation in HIV-Associated Airway Disease

Blood will be drawn for plasma, serum, and peripheral blood mononuclear cells.

The following questionnaires are administered to participants by study personnel: Gingo Asthma Questionnaire (GAQ) and the Asthma Quality of Life questionnaire (AQL).

Spirometry is a simple breathing test that measures the amount of air in one's lungs and how well one can move that air by forcefully blowing 3 or more times into a mouthpiece. A series of these maneuvers will be performed under the instruction of a respiratory technician or respiratory therapist.

A methacholine challenge is a common test often used to support a diagnosis of asthma. The test consists of inhaling increasing doses of methacholine through a nebulizer to assess how quickly the participant's airways narrow.

There will be a standard chest CT and an abdominal CT. The CT scans capture contiguous volume scans acquired at slice thicknesses of 5.0 mm in the axial plane and reconstructed with 512 x 512 pixel matrices. CT examinations will encompass the entire thorax and the abdomen and will be performed during a breath-hold at end-inspiration. The investigators will measure % of lung tissue below a threshold for emphysema (i.e. -950 Hounsfield units). Measurements have been histologically-verified and give reproducible measurements. The data set is assembled and analyzed with the image data anonymized. If the participant has had a research chest CT scan done recently, only the abdomen CT will be done.

All female participants with childbearing potential will be asked to provide a urine sample for pregnancy testing. The result of the pregnancy test must be negative in order for her to be in this research study.

The doctor will obtain a sample of fat cells from the participant's abdomen. Numbing medicine will be applied. A needle is placed through the skin \& into the fat pad under the skin. A blunt-tip hollow cannula is then used to aspirate fat tissue through the incision.

The investigators will measure concentrations of exhaled nitric oxide by asking the participant to inhale deeply, and then exhale very slowly into a mouthpiece for between 10-15 seconds.