title: Lung diffusing capacity relates better to short-term progression on HRCT abnormalities than spirometry in mild asbestosis.
abstract: BACKGROUND
  Pulmonary function tests (PFT), particularly spirometry and lung diffusing capacity for carbon monoxide (DL(CO) ), have been considered useful methods for the detection of the progression of interstitial asbestos abnormalities as indicated by high-resolution computed tomography (HRCT). However, it is currently unknown which of these two tests correlates best with anatomical changes over time.
  
  
  METHODS
  In this study, we contrasted longitudinal changes (3-9 years follow-up) in PFTs at rest and during exercise with interstitial abnormalities evaluated by HRCT in 63 ex-workers with mild-to-moderate asbestosis.
  
  
  RESULTS
  At baseline, patients presented with low-grade asbestosis (Huuskonen classes I-II), and most PFT results were within the limits of normality. In the follow-up, most subjects had normal spirometry, static lung volumes and arterial blood gases. In contrast, frequency of DL(CO) abnormalities almost doubled (P < 0.05). Twenty-three (36.5%) subjects increased the interstitial marks on HRCT. These had significantly larger declines in DL(CO) compared to patients who remained stable (0.88 vs. 0.31 ml/min/mm Hg/year and 3.5 vs. 1.2%/year, respectively; P < 0.05). In contrast, no between-group differences were found for the other functional tests, including spirometry (P > 0.05).
  
  
  CONCLUSIONS
  These data demonstrate that the functional consequences of progression of HRCT abnormalities in mild-to-moderate asbestosis are better reflected by decrements in DL(CO) than by spirometric changes. These results might have important practical implications for medico-legal evaluation of this patient population.
authors.affiliation: Respiratory Division, Federal University of São Paulo (UNIFESP), Rua Botucatu 740, São Paulo, SP, Brazil.
authors.forename: Cristiano Rabelo
authors.initials: CR
authors.lastname: Nogueira
authors.forename: Lara Maris
authors.initials: LM
authors.lastname: Nápolis
authors.forename: Ericson
authors.initials: E
authors.lastname: Bagatin
authors.forename: Mario
authors.initials: M
authors.lastname: Terra-Filho
authors.forename: Nestor L
authors.initials: NL
authors.lastname: Müller
authors.forename: C Isabela S
authors.initials: CI
authors.lastname: Silva
authors.forename: Reynaldo Tavares
authors.initials: RT
authors.lastname: Rodrigues
authors.forename: J Alberto
authors.initials: JA
authors.lastname: Neder
authors.forename: Luiz E
authors.initials: LE
authors.lastname: Nery
mesh_terms: D017632:Asbestos, Serpentine / Q000633:toxicity; D001195:Asbestosis / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology; D018450:Disease Progression; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009784:Occupational Diseases / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology; D016273:Occupational Exposure / Q000009:adverse effects; D011446:Prospective Studies; D011653:Pulmonary Diffusing Capacity / Q000295:instrumentation* / Q000379:methods; D012129:Respiratory Function Tests; D012720:Severity of Illness Index; D013997:Time Factors; D014057:Tomography, X-Ray Computed / Q000295:instrumentation* / Q000379:methods
chemical_list: D017632:Asbestos, Serpentine