title: Adiposity influences airway wall thickness and the asthma phenotype of HIV-associated obstructive lung disease: a cross-sectional study.
abstract: BACKGROUND
  Airflow obstruction, which encompasses several phenotypes, is common among HIV-infected individuals. Obesity and adipose-related inflammation are associated with both COPD (fixed airflow obstruction) and asthma (reversible airflow obstruction) in HIV-uninfected persons, but the relationship to airway inflammation and airflow obstruction in HIV-infected persons is unknown. The objective of this study was to determine if adiposity and adipose-associated inflammation are associated with airway obstruction phenotypes in HIV-infected persons.
  
  
  METHODS
  We performed a cross-sectional analysis of 121 HIV-infected individuals assessed with pulmonary function testing, chest CT scans for measures of airway wall thickness (wall area percent [WA%]) and adipose tissue volumes (mediastinal and subcutaneous), as well as HIV- and adipose-related inflammatory markers. Participants were defined as COPD phenotype (post-bronchodilator FEV1/FVC < lower limit of normal) or asthma phenotype (doctor-diagnosed asthma or bronchodilator response). Pearson correlation coefficients were calculated between adipose measurements, WA%, and pulmonary function. Multivariable logistic and linear regression models were used to determine associations of airflow obstruction and airway remodeling (WA%) with adipose measurements and participant characteristics.
  
  
  RESULTS
  Twenty-three (19 %) participants were classified as the COPD phenotype and 33 (27 %) were classified as the asthma phenotype. Body mass index (BMI) was similar between those with and without COPD, but higher in those with asthma compared to those without (mean [SD] 30.7 kg/m(2) [8.1] vs. 26.5 kg/m(2) [5.3], p = 0.008). WA% correlated with greater BMI (r = 0.55, p < 0.001) and volume of adipose tissue (subcutaneous, r = 0.40; p < 0.001; mediastinal, r = 0.25; p = 0.005). Multivariable regression found the COPD phenotype associated with greater age and pack-years smoking; the asthma phenotype with younger age, female gender, smoking history, and lower adiponectin levels; and greater WA% with greater BMI, younger age, higher soluble CD163, and higher CD4 counts.
  
  
  CONCLUSIONS
  Adiposity and adipose-related inflammation are associated with an asthma phenotype, but not a COPD phenotype, of obstructive lung disease in HIV-infected persons. Airway wall thickness is associated with adiposity and inflammation. Adipose-related inflammation may play a role in HIV-associated asthma.
authors.affiliation: Department of Medicine, University of Pittsburgh, Pittsburgh, USA.
authors.forename: Julia H
authors.initials: JH
authors.lastname: Barton
authors.affiliation: Department of Medicine, University of Pittsburgh, Pittsburgh, USA.
authors.forename: Alex
authors.initials: A
authors.lastname: Ireland
authors.affiliation: Department of Medicine, University of Pittsburgh, Pittsburgh, USA.
authors.forename: Meghan
authors.initials: M
authors.lastname: Fitzpatrick
authors.affiliation: Department of Medicine, University of Pittsburgh, Pittsburgh, USA.
authors.forename: Cathy
authors.initials: C
authors.lastname: Kessinger
authors.affiliation: Department of Medicine, University of Pittsburgh, Pittsburgh, USA.
authors.forename: Danielle
authors.initials: D
authors.lastname: Camp
authors.affiliation: Department of Medicine, University of Pittsburgh, Pittsburgh, USA.
authors.forename: Renee
authors.initials: R
authors.lastname: Weinman
authors.affiliation: Department of Medicine, University of Pittsburgh, Pittsburgh, USA.
authors.forename: Deborah
authors.initials: D
authors.lastname: McMahon
authors.affiliation: Department of Medicine, University of Pittsburgh, Pittsburgh, USA.
authors.forename: Joseph K
authors.initials: JK
authors.lastname: Leader
authors.affiliation: Department of Medicine, University of Pittsburgh, Pittsburgh, USA.|Department of Pediatrics, University of Pittsburgh, Pittsburgh, USA.
authors.forename: Fernando
authors.initials: F
authors.lastname: Holguin
authors.affiliation: Department of Medicine, University of Pittsburgh, Pittsburgh, USA.
authors.forename: Sally E
authors.initials: SE
authors.lastname: Wenzel
authors.affiliation: Department of Medicine, University of Pittsburgh, Pittsburgh, USA.|Department of Immunology, University of Pittsburgh, Pittsburgh, USA.
authors.forename: Alison
authors.initials: A
authors.lastname: Morris
authors.affiliation: Department of Medicine, University of Pittsburgh, Pittsburgh, USA. gingomr@upmc.edu.|Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, University of Pittsburgh, 3459 Fifth Avenue, 628 NW, Pittsburgh, PA, 15213, USA. gingomr@upmc.edu.
authors.forename: Matthew R
authors.initials: MR
authors.lastname: Gingo
mesh_terms: D000328:Adult; D056151:Airway Remodeling; D001249:Asthma / Q000000981:diagnostic imaging / Q000453:epidemiology*; D015992:Body Mass Index; D003430:Cross-Sectional Studies; D005260:Female; D005541:Forced Expiratory Volume; D015658:HIV Infections / Q000150:complications*; D006801:Humans; D016014:Linear Models; D016015:Logistic Models; D008168:Lung / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009765:Obesity / Q000453:epidemiology*; D010414:Pennsylvania; D010641:Phenotype; D029424:Pulmonary Disease, Chronic Obstructive / Q000000981:diagnostic imaging / Q000453:epidemiology*; D012907:Smoking / Q000453:epidemiology*; D014057:Tomography, X-Ray Computed
keywords: Adiponectin; Asthma; COPD; HIV; Lipodystrophy; Obesity; Obstructive lung disease