Background: The Medical Research Council (MRC) chronic dyspnea scale (6-point) is used in different clinical conditions to grade breathlessness on daily activities. We have previously shown that in patients with histologically documented usual interstitial pneumonia/idiopathic pulmonary fibrosis (UIP/IPF), the MRC dyspnea scale is useful in estimating disease severity. The aim of this study was to further investigate the usefulness of the MRC scale in IPF as a marker of survival.
Methods: The records of 25 patients with histologically documented UIP/IPF were retrospectively reviewed. Clinical parameters, pulmonary function tests, and arterial blood gases at the time of diagnosis, as well as survival time were retrieved and recorded for each patient. The impact of the different variables determined at diagnosis on survival was examined using the Kaplan-Meier and uni- and multi-variate Cox-regression analyses.
Results: Among the baseline clinical and physiologic parameters determined at the time of IPF diagnosis, the MRC score, the Tiffeneau index, and the total lung capacity were the only significant and independent predictors of survival. In specific, a high MRC score, a high Tiffeneau index, and a low total lung capacity at presentation were associated with shorter survival.
Conclusion: In accordance with the previous work, our results indicate that the Tiffeneau index and total lung capacity (TLC) are the important determinants of survival in patients with IPF. In addition, we show that the simple MRC chronic dyspnea score estimated at the time of diagnosis is equally predictive of survival and may aid clinicians in assessing the prognosis of new cases of IPF.