title: A Low Peripheral Blood CD4/CD8 Ratio Is Associated with Pulmonary Emphysema in HIV.
abstract: OBJECTIVE
  The prevalence of emphysema is higher among HIV-infected (HIV+) individuals compared to HIV-uninfected persons. While greater tobacco use contributes, HIV-related effects on immunity likely confer additional risk. Low peripheral blood CD4+ to CD8+ T-lymphocyte (CD4/CD8) ratio may reflect chronic inflammation in HIV and may be a marker of chronic lung disease in this population. Therefore, we sought to determine whether the CD4/CD8 ratio was associated with chronic obstructive pulmonary disease (COPD), particularly the emphysema subtype, in a cohort of HIV+ subjects.
  
  
  METHODS
  We performed a cross-sectional analysis of 190 HIV+ subjects enrolled in the Examinations of HIV Associated Lung Emphysema (EXHALE) study. Subjects underwent baseline laboratory assessments, pulmonary function testing and chest computed tomography (CT) analyzed for emphysema severity and distribution. We determined the association between CD4/CD8 ratio and emphysema, and the association between CD4/CD8 ratio and pulmonary function markers of COPD.
  
  
  RESULTS
  Mild or greater emphysema (>10% lung involvement) was present in 31% of subjects. Low CD4/CD8 ratio was associated with >10% emphysema in multivariable models, adjusting for risk factors including smoking, current and nadir CD4 count and HIV RNA level. Those with CD4/CD8 ratio <0.4 had 6.3 (1.1-39) times the odds of >10% emphysema compared to those with a ratio >1.0 in fully adjusted models. A low CD4/CD8 ratio was also associated with reduced diffusion capacity (DLCO).
  
  
  CONCLUSIONS
  A low CD4/CD8 ratio was associated with emphysema and low DLCO in HIV+ subjects, independent of other risk factors and clinical markers of HIV. The CD4/CD8 ratio may be a useful, clinically available, marker for risk of emphysema in HIV+ subjects in the antiretroviral therapy (ART) era.
authors.affiliation: Department of Medicine, University of Washington, Seattle, Washington, United States of America.
authors.forename: Matthew
authors.identifier: http://orcid.org/0000-0001-7421-4720
authors.initials: M
authors.lastname: Triplette
authors.affiliation: Department of Medicine, University of Washington, Seattle, Washington, United States of America.
authors.forename: Engi F
authors.initials: EF
authors.lastname: Attia
authors.affiliation: Department of Medicine, Veterans Affairs Connecticut Healthcare System, New Haven, Connecticut, United States of America.|Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut, United States of America.
authors.forename: Kathleen M
authors.initials: KM
authors.lastname: Akgün
authors.affiliation: Department of Medicine, Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, California, United States of America.|Department of Medicine, David Geffen School of Medicine at UCLA, Los Angeles, California, United States of America.
authors.forename: Guy W
authors.initials: GW
authors.lastname: Soo Hoo
authors.affiliation: Department of Medicine, Vanderbilt University, Nashville, Tennessee, United States of America.
authors.forename: Matthew S
authors.initials: MS
authors.lastname: Freiberg
authors.affiliation: Department of Medicine, Weill Cornell Medical College, New York, New York, United States of America.|Hamad Healthcare Quality Institute and Medical Corporation, Doha, Qatar.
authors.forename: Adeel A
authors.initials: AA
authors.lastname: Butt
authors.affiliation: Department of Medicine, Atlanta Veterans Affairs Medical Center, Atlanta, Georgia, United States of America.|Department of Medicine, Emory University School of Medicine, Atlanta, Georgia, United States of America.
authors.forename: Cherry
authors.initials: C
authors.lastname: Wongtrakool
authors.affiliation: Department of Medicine, Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, California, United States of America.|Department of Medicine, David Geffen School of Medicine at UCLA, Los Angeles, California, United States of America.
authors.forename: Matthew Bidwell
authors.initials: MB
authors.lastname: Goetz
authors.affiliation: Department of Medicine, James J. Peters Veterans Affairs Medical Center, New York, New York, United States of America.|Department of Medicine, Icahn School of Medicine at Mt. Sinai, New York, New York, United States of America.
authors.forename: Sheldon T
authors.initials: ST
authors.lastname: Brown
authors.affiliation: Department of Medicine, Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, California, United States of America.|Department of Medicine, David Geffen School of Medicine at UCLA, Los Angeles, California, United States of America.
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Graber
authors.affiliation: Department of Medicine, University of California San Francisco, San Francisco, California, United States of America.
authors.forename: Laurence
authors.initials: L
authors.lastname: Huang
authors.affiliation: Department of Medicine, University of Washington, Seattle, Washington, United States of America.
authors.forename: Kristina
authors.initials: K
authors.lastname: Crothers
mesh_terms: D000328:Adult; D016516:CD4-CD8 Ratio; D003430:Cross-Sectional Studies; D005260:Female; D015658:HIV Infections / Q000150:complications / Q000000981:diagnostic imaging / Q000276:immunology*; D006801:Humans; D018655:Lymphocyte Count; D008297:Male; D008875:Middle Aged; D011656:Pulmonary Emphysema / Q000150:complications / Q000000981:diagnostic imaging / Q000276:immunology*; D013902:Radiography, Thoracic; D012129:Respiratory Function Tests; D012307:Risk Factors; D014057:Tomography, X-Ray Computed