Risk factors and outcomes of pericardial effusion in cancer patients receiving PD-1 inhibitors

Background Programmed cell death 1 (PD-1) inhibitors can induce various adverse reactions associated with immunity, of which cardiotoxicity is a serious complication. Limited research exists on the link between PD-1 inhibitor use and pericardial effusion (PE) occurrence and outcomes. Methods We conducted a retrospective study at the First Affiliated Hospital of Xi'an Jiaotong University from 2017 to 2019, comparing cancer patients who developed PE within 2 years after PD-1 inhibitor therapy to those who did not. Our primary outcome was the all-cause mortality rate at one year. We applied the Kaplan-Meier method for survival analysis. Multivariate logistic regression was utilized to identify PE risk factors, adjusting for potential confounders. Results A total of 91 patients were finally included, of whom 39 patients had PE. Compared to non-PE group, one-year all-cause mortality was nearly 5 times higher in PE group (64.10% vs. 13.46%, P < 0.001). Patients who developed PE within 2 years of taking PD-1 inhibitors were significantly associated with increased all-cause mortality compared with those who did not (HR: 6.26, 95%CI: 2.70–14.53, P < 0.001). Multivariable logistic regression showed that use of sintilimab (OR: 14.568, 95%CI: 3.431–61.857, P < 0.001), history of lung cancer (OR: 15.360, 95%CI: 3.276–72.017, P = 0.001), and history of hypocalcemia (OR: 7.076, 95%CI: 1.879–26.649, P = 0.004) were independent risk factors of PE development in patients received PD-1 inhibitors therapy. Conclusions The use of PD-1 inhibitors raises PE risk in cancer patients, especially those with lung cancer and hypocalcemia, and is linked to higher one-year mortality in PE patients.