Interestingly, Nicholson et al demonstrated that increasing semiquantitative FF score was independently associated with greater declines at both 6 months and 12 months in FVC and carbon monoxide diffusing capacity in IPF. Unfortunately, we did not examine the trends of pulmonary function tests at such intervals. Thus, further studies will be needed to clarify whether our quantitative %FF score is related to functional decline. There was no correlation between the quantitative %FF score and BAL findings in CVD-UIP, while the quantitative %FF score was significantly correlated with the percentage of neutrophils (p = 0.026, r = 0.55), and eosinophils (p = 0.046, r = 0.50) in IPF. Interestingly, previous studies demonstrated that higher percentages of neutrophils or eosinophils were associated with more extensive disease and poor prognosis in IPF. Although the correlation rates were not high, there might be some association between extent of FF and the number of BAL neutrophils and eosinophils. canadian neighbor pharmacy
Our previous study showed CVD-UIP had more favorable prognosis than IPF. In the present study, we found that patients with CVD-UIP had significantly lower %FF scores and a better prognosis than those with IPF. Consistent with our results, Flaherty et al showed that the degree of FF was smaller in CVD-UIP than in IPF/UIP, as assessed by their semiquantitative scoring method, which might be associated with the favorable prognosis of CVD-UIP. The reason for the variation in the degree of FF between IPF and CVD-UIP is unclear. The etiology is thought to differ between IPF and CVD-UIP: the formation of FF might be induced by the injury of the alveolar epithelium in IPF, while endothelial injury probably causes FF formation in CVD-UIP. This etiologic difference might be responsible for the variation in the degree of FF. In addition, the present data demonstrated that the quantitative %FF score was an independent predictor of prognosis in the multivariate Cox proportional hazards regression model adjusted by IPF/UIP diagnosis, suggesting that FF play a pivotal role in determining the prognosis of patients having UIP, regardless of etiology.
The main weakness of the present study is its retrospective design and the relatively small number of patients. In addition, the survival rate of our IPF patients seemed to be relatively higher than that of typical IPF patients. Approximately 38% of our IPF patients came to the hospital because of interstitial abnormalities on the chest radiograph of annual medical checkups without respiratory symptoms, suggesting that our study population included early stage IPF patients. This may account for the relatively better prognosis of our IPF patients. To confirm our findings, larger prospective studies will be required.
In conclusion, our quantitative FF scoring method using a CCD camera and analytic software, which is easily performed, is more objective and quantitative than previously reported semiquantitative scoring methods, and provides accurate information about prognosis in patients with UIP.