Natural history and prognosis of advanced lung disease.

Large gaps exist in our knowledge of the natural history of advanced lung disease and of the impact of various therapies upon prognosis and survival. Applying the results of population-based epidemiologic studies or limited clinical trials to a specific patient is hazardous because of marked individual variation in survival, even with the most grim of prognoses. Obtaining such prognostic information is essential, however, in addressing current key issues in advanced lung disease-the efficacy of various therapies, timing lung transplantation, referring to hospice care, providing palliative therapy, and determining medical futility.