Clinical Implications of the Controlling Nutritional Status Score on Short-term Outcomes in Patients with Pleural Infection

OBJECTIVE: Pleural infection is a significant disease that continues to pose severe problems for respiratory physicians. However, prognostic factors of pleural infection remain poorly understood. The controlling nutritional status (CONUT) score represents the immune-nutrition status of patients with chronic infectious diseases. This study investigated its prognostic value in patients with pleural infections. METHODS: We retrospectively analyzed a collected database of 2,363 patients who underwent thoracentesis and pleural fluid analyses between January 2010 and December 2019. Of these, only 335 patients with complicated parapneumonic effusion and empyema defined as pleural infection were included. They were divided into two groups based on the dichotomized CONUT score (i.e. <6 for low scores and ≥6 for high scores). The primary outcome was all-cause mortality within 90 days from the time of pleural fluid collection. RESULTS: Overall mortality was 8.4% at 3 months (28 out of 335). The incidence of 90-day mortality was higher in patients with higher CONUT scores than in those with lower scores [25.3% (21/84) vs. 2.8% (7/251), p<0.001]. In addition, after adjusting for confounders, a high CONUT score was found to be an independent prognostic factor for 90-day mortality (hazard ratio, 9.30; 95% confidence interval, 3.96-21.87; p<0.001). CONCLUSION: Our study indicated that a high CONUT score was associated with an increased risk of 90-day mortality in patients with pleural infection and can be considered for clinical evaluations in practice.