In this issue of CHEST (see page 614), Theodore et al1 examined whether cough is related to disease activity and its response to immunosuppressive therapy. Most of the subjects in the study had dry, intermittent, mild to moderate cough. Only 5% (n =6) reported severe persistent cough, and only 9% had productive cough. They found that only cough frequency, but not severity or phlegm production, correlated with lower physical quality of life, more dyspnea, and lower diffusing capacity of the lung for carbon monoxide. Subjects who reported cough as a symptom had more fibrosis (higher lung and skin fibrosis scores) when compared with subjects without cough. After 1 year of treatment with cyclophosphamide, the percentage of subjects reporting cough decreased over the 6- to 18-month time period. The improvement was not sustained and was gone by 24 months. Based on these findings, the authors suggest that cough may be a surrogate measure of ongoing fibrosis and alveolar inflammation.