Key predictive features identified in the CatBoost model encompassed the Oxygenation Index, indicating respiratory function; cTnT, reflecting cardiac stress; MFG-E8, whose lower levels in deceased patients suggested a protective role against inflammation; dyspnea, correlating with disease severity; CTGF, associated with fibrosis and poor prognosis and PaCO2, indicating respiratory failure. The gene discussed is CCN2; the disease is respiratory failure.