Background:

Serum C-reactive protein (CRP) to albumin ratio (CAR) has been defined as an inflammation-based prognostic marker. We evaluated the association and prognostic value of CRP/albumin ratio in patients with pulmonary embolism (PE).

Methods:

A total of 256 patients with acute PE who were hospitalized between March 2016 and December 2020 were retrospectively reviewed. PE severity index (PESI) was calculated. Serum levels of CRP and albumin that were obtained at the time of admission were used for calculation. CAR was evaluated for correlation with PESI, and thus, foresee the risk of death due to PE.

Results:

There were 186 patients eligible for inclusion. 54 patients were in intermediate, 34 patients were in high risk and 98 patients were in very high-risk group according to PESI score. In the correlation analysis, we observed moderate positive correlations between CRP/albumin ratio, troponin and PESI score (r = 0.584, p < 0.0001; r = 521, p < 0.0001, respectively). Regression analysis revealed that only CRP/albumin ratio and PESI score were independent risk factors associated with 6-month mortality of acute PE patients. The AUC for CRP/albumin ratio was 0.643, 0.751, and 0.763 for 30-day, 90-day, and 6-month mortality, respectively (95% CI: 0.550-0.737, 0.672-0.830, 0.687-0.838]. A cut-off value of 5.33 for CRP/albumin ratio was associated with 65.3% sensitivity and 65.6% specificity in predicting 6-month mortality.

Conclusion:

The CRP/albumin ratio, an inexpensive and easily measurable laboratory variable, may be a useful prognostic marker of PE, especially when other causes that alter serum levels are excluded from the study.