Age and Small Airway Imaging Abnormalities in Subjects with and without Airflow Obstruction in SPIROMICS.

TitleAge and Small Airway Imaging Abnormalities in Subjects with and without Airflow Obstruction in SPIROMICS.
Publication TypePublication
Year2017
AuthorsMartinez CH, Diaz AA, Meldrum C, Curtis JL, Cooper CB, Pirozzi C, Kanner RE, Paine R, Woodruff PG, Bleecker ER, Hansel NN, R Barr G, Marchetti N, Criner GJ, Kazerooni EA, Hoffman EA, Ross BD, Galbán CJ, Cigolle CT, Martinez FJ, Han MK
Corporate AuthorsSPIROMICS Investigators
JournalAm J Respir Crit Care Med
Volume195
Issue4
Pagination464-472
Date Published2017 Feb 15
ISSN1535-4970
KeywordsAdult, Aged, Aged, 80 and over, Aging, airway obstruction, Cohort Studies, Cross-Sectional Studies, Female, Forced Expiratory Volume, Humans, Lung, Male, Middle Aged, Multicenter Studies as Topic, Multivariate Analysis, Pulmonary Emphysema, smoking, Spirometry, Tomography, X-Ray Computed, Vital Capacity
Abstract

RATIONALE: Aging is associated with reduced FEV to FVC ratio (FEV/FVC), hyperinflation, and alveolar enlargement, but little is known about how age affects small airways.OBJECTIVES: To determine if chest computed tomography (CT)-assessed functional small airway would increase with age, even among asymptomatic individuals.METHODS: We used parametric response mapping analysis of paired inspiratory/expiratory CTs to identify functional small airway abnormality (PRM) and emphysema (PRM) in the SPIROMICS (Subpopulations and Intermediate Outcome Measures in COPD Study) cohort. Using adjusted linear regression models, we analyzed associations between PRM and age in subjects with or without airflow obstruction. We subdivided participants with normal spirometry based on respiratory-related impairment (6-minute-walk distance <350 m, modified Medical Research Council ≥2, chronic bronchitis, St. George's Respiratory Questionnaire >25, respiratory events requiring treatment [antibiotics and/or steroids or hospitalization] in the year before enrollment).MEASUREMENTS AND MAIN RESULTS: Among 580 never- and ever-smokers without obstruction or respiratory impairment, PRM increased 2.7% per decade, ranging from 3.6% (ages 40-50 yr) to 12.7% (ages 70-80 yr). PRM increased nonsignificantly (0.1% [ages 40-50 yr] to 0.4% [ages 70-80 yr]; P = 0.34). Associations were similar among nonobstructed individuals with respiratory-related impairment. Increasing PRM in subjects without airflow obstruction was associated with increased FVC (P = 0.004) but unchanged FEV (P = 0.94), yielding lower FEV/FVC ratios (P < 0.001). Although emphysema was also significantly associated with lower FEV/FVC (P = 0.04), its contribution relative to PRM in those without airflow obstruction was limited by its low burden.CONCLUSIONS: In never- and ever-smokers without airflow obstruction, aging is associated with increased FVC and CT-defined functional small airway abnormality regardless of respiratory symptoms.

DOI10.1164/rccm.201604-0871OC
Alternate JournalAm. J. Respir. Crit. Care Med.
PubMed ID27564413
PubMed Central IDPMC5378423
Grant ListT32 HL007749 / HL / NHLBI NIH HHS / United States
R01 HL089897 / HL / NHLBI NIH HHS / United States
HHSN268200900019C / HL / NHLBI NIH HHS / United States
HHSN268200900009C / WH / WHI NIH HHS / United States
S10 OD018526 / OD / NIH HHS / United States
P30 ES005605 / ES / NIEHS NIH HHS / United States
K08 AG031837 / AG / NIA NIH HHS / United States
K23 HL128936 / HL / NHLBI NIH HHS / United States
U01 HL089897 / HL / NHLBI NIH HHS / United States
R01 HL089856 / HL / NHLBI NIH HHS / United States
K01 HL118714 / HL / NHLBI NIH HHS / United States
U01 HL089856 / HL / NHLBI NIH HHS / United States
HHSN268200900015C / HL / NHLBI NIH HHS / United States
HHSN268200900016C / HL / NHLBI NIH HHS / United States
I01 CX000911 / CX / CSRD VA / United States
U01 HL137880 / HL / NHLBI NIH HHS / United States
R01 HL122438 / HL / NHLBI NIH HHS / United States
R44 HL118837 / HL / NHLBI NIH HHS / United States
HHSN268200900018C / HL / NHLBI NIH HHS / United States
P30 DK054759 / DK / NIDDK NIH HHS / United States
HHSN268200900017C / HL / NHLBI NIH HHS / United States
HHSN268200900020C / HL / NHLBI NIH HHS / United States
HHSN268200900013C / HL / NHLBI NIH HHS / United States
P01 CA085878 / CA / NCI NIH HHS / United States
HHSN268200900014C / HL / NHLBI NIH HHS / United States
K24 HL138188 / HL / NHLBI NIH HHS / United States
MS#: 
MS051
Manuscript Lead/Corresponding Author Affiliation: 
Clinical Center: Michigan (University of Michigan)
ECI: 
Manuscript Status: 
Published