Predicting Long-Term Outcomes in Pleural Infections. RAPID Score for Risk Stratification

Pleural infections are associated with significant morbidity and mortality. The recently developed RAPID (renal, age, purulence, infection source, and dietary factors) score consists of five clinical factors that can identify patients at risk for increased mortality.

The objective of this study was to further validate the RAPID score in a diverse cohort, identify factors associated with mortality, and provide long-term outcomes.

We evaluated a single-center retrospective cohort of 187 patients with culture-positive pleural infections. Patients were classified by RAPID scores into low-risk (0-2), medium-risk (3-4), and high-risk (5-7) groups. The Social Security Death Index was used to determine date of death. All-cause mortality was assessed at 3 months, 1 year, 3 years, and 5 years. Clinical factors and comorbid conditions were evaluated for association.

Three-month mortality for low-, medium-, and high-risk groups was 1.5, 17.8, and 47.8%, respectively. Increased odds were observed among medium-risk (odds ratio, 14.3; 95% confidence interval, 1.8-112.6; P = 0.01) and high-risk groups (odds ratio, 53.3; 95% confidence interval, 6.8-416.8; P < 0.01). This trend continued at 1, 3, and 5 years. Factors associated with high-risk scores include gram-negative rod infections, heart disease, diabetes, cancer, lung disease, and increased length of stay.

When applied to a diverse patient cohort, the RAPID score predicts outcomes in patients up to 5 years and may aid in long-term risk stratification on presentation.