Clinical characteristics in patients with asymmetric idiopathic pulmonary fibrosis.
A group of patients with idiopathic pulmonary fibrosis (IPF) presents with disease affecting one lung markedly more than the other. At this time, it is unclear how this population differs from those who present with more symmetric disease. We sought to explain the characteristics of the asymmetric group and how their disease progresses.



In this retrospective case-control study we accessed an interstitial lung disease (ILD) database and identified 14 asymmetric IPF cases via high-resolution computed tomography (HRCT) scoring of each lung lobe's disease severity. We identified 28 symmetric IPF controls from the same database using the same methods, and compared the clinical features of each group.



Patients with asymmetric disease exhibited similar demographics as those in the general IPF population; they were predominantly male (64%), elderly (69 years old), and used tobacco (57%). We found a trend toward significantly increased all-cause mortality in the case population two years following diagnosis (p = 0.089). Pulmonary function tests were significantly lower in the case group at the time of diagnosis, then both groups experienced gradual decline. We found no statistically significant differences in number of IPF exacerbations (cases 43%, controls 39%, p = 0.824) and gastro-esophageal reflux (both groups 50%).



Patients with asymmetric IPF resemble patients in the general IPF population but may have a lower overall survival rate. Further systemic factors may be studied to identify reasons for disease asymmetry and clinical decline in this population.
Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Virginia Health System, P.O. Box 800546, Charlottesville, VA 22908, USA. Electronic address: sjc4z@virginia.edu.
Sean J
SJ
Callahan
Department of Biostatistics, University of Michigan, 1415 Washington Heights, Ann Arbor, MI 48109, USA.
Meng
M
Xia
Department of Biostatistics, University of Michigan, 1415 Washington Heights, Ann Arbor, MI 48109, USA.
Susan
S
Murray
Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan Health System, 1500 East Medical Center Drive, Ann Arbor, MI 48109, USA.
Kevin R
KR
Flaherty
D000368:Aged; D001706:Biopsy; D002248:Carbon Monoxide / Q000378:metabolism; D016022:Case-Control Studies; D018450:Disease Progression; D005260:Female; D005541:Forced Expiratory Volume / Q000502:physiology; D006801:Humans; D054990:Idiopathic Pulmonary Fibrosis / Q000000981:diagnostic imaging* / Q000453:epidemiology / Q000473:pathology / Q000503:physiopathology*; D008168:Lung / Q000000981:diagnostic imaging* / Q000473:pathology / Q000503:physiopathology*; D017563:Lung Diseases, Interstitial / Q000000981:diagnostic imaging / Q000473:pathology / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D011653:Pulmonary Diffusing Capacity / Q000502:physiology; D012129:Respiratory Function Tests / Q000379:methods; D012189:Retrospective Studies; D015996:Survival Rate; D064424:Tobacco Use / Q000009:adverse effects; D014057:Tomography, X-Ray Computed / Q000379:methods; D014797:Vital Capacity / Q000502:physiology
D002248:Carbon Monoxide
Asymmetric; Fibrosis; High resolution CT; Honeycombing; IPF; Surgical lung biopsy
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