Non-specific interstitial pneumonia in cigarette smokers: a CT study

Abstract

The goal of this study was to seek indirect evidence that smoking is an aetiological factor in some patients with non-specific interstitial pneumonia (NSIP). Ten current and eight exsmokers with NSIP were compared to controls including 137 current smokers with no known interstitial lung disease and 11 non-smokers with NSIP. Prevalence and extent of emphysema in 18 smokers with NSIP were compared with subjects meeting GOLD criteria for chronic obstructive pulmonary disease (COPD; group A; n=34) and healthy smokers (normal FEV 1 ; group B; n=103), respectively. Emphysema was present in 14/18 (77.8%) smokers with NSIP. Emphysema did not differ in prevalence between NSIP patients and group A controls (25/34, 73.5%), but was strikingly more prevalent in NSIP patients than in group B controls (18/103, 17.5%, P<0.0005). On multiple logistic regression, the likelihood of emphysema increased when NSIP was present (OR=18.8; 95% CI=5.3-66.3; P<0.0005) and with increasing age (OR=1.04; 95% CI=0.99-1.11; P=0.08). Emphysema is as prevalent in smokers with NSIP as in smokers with COPD, and is strikingly more prevalent in these two groups than in healthy smoking controls. The association between NSIP and emphysema provides indirect support for a smoking pathogenesis hypothesis in some NSIP patients.

Idiopathic nonspecific interstitial pneumonia: an interstitial lung disease associated with autoimmune disorders?

“…To the best of our knowledge, no previously published paper on iNSIP has ever shown this finding. The data related to the group of patients who did not develop any autoimmune disease (younger, predominantly smoking) might support the hypothesis of another NSIP phenotype, with a possible smoking pathogenesis, as previously suggested [9,10].…”

“…The association of the presence of emphysema in smoking patients with iNSIP [9], and the evolution into a pattern resembling fibrosing NSIP of some cases of desquamative interstitial pneumonia, typically associated with cigarette smoking [10], provide indirect support also for a smoking-related pathogenesis, at least in some iNSIP cases. We hypothesised that the distinct clinical entity iNSIP might be associated with an autoimmune background that later reveals itself as an organ-specific or a systemic autoimmune disease.…”

The pulmonary histopathologic manifestations of the anti-Jo-1 tRNA synthetase syndrome

“…Interestingly, as noted in the literature, there is a subgroup of 'typical' nonspecific interstitial pneumonia patients who on longitudinal radiographic study progress to a pattern of lung damage resembling usual interstitial pneumonia who are captured only by studies containing autopsy and lung transplant cases. 29,30 Coupled with our observation of a high percentage of usual interstitial pneumonia patterns of fibrosis, such clinical data suggests that nonspecific interstitial pneumonia in the anti-Jo-1 population could evolve over time into a usual interstitial pneumonia pattern of fibrosis as well as traditional fibrotic forms of nonspecific interstitial pneumonia. This possibility should be addressed in future autopsy studies of nonspecific interstitial pneumonia.…”

The impact of emphysema in pulmonary fibrosis

“…CPFE is most often observed in males (mean age of 65 years) who are tobacco smokers or ex-smokers of .40 pack-years [9,10]. CPFE has a poor prognosis, with a 5-year survival of 55% [4].…”

“…Basal crackles are heard on auscultation (table 1) [4,9]. Severe impairment in gas exchange often parallels significant exercise limitation and contrasts with the relative lack of clinical manifestation at rest.…”