Abstract: Objective: To explore the effects of programmed death-1 (PD-1) inhibitor combined with chemotherapy versus chemotherapy alone on the incidence of acute kidney injury (AKI) and long-term renal function in tumor patients.

Methods: A retrospective cohort study was conducted. Clinical data were collected from 311 hospitalized tumor patients between January 2018 and December 2024. Patients were divided into the combination therapy group and the chemotherapy-alone group according to the treatment regimen. Baseline and post-treatment clinical data were collected, and the decline rate of estimated glomerular filtration rate (eGFR) and incidence of AKI were recorded at the 1st, 3rd, 6th and 12th months after treatment initiation. The incidence of eGFR decline and AKI at each time point were recorded. A linear mixed model was adopted to analyze the changing trend of eGFR over time. The Kaplan-Meier method was used to assess the cumulative incidence of AKI and eGFR decline, and the Cox proportional hazards model was applied to analyze the related factors affecting renal function outcomes.

Results: (1) The incidence of AKI (14.7% vs 5.4%) and eGFR decline (41.1% vs 25.0%) in the combination therapy group were significantly higher than those in the chemotherapy-alone group. (2) Survival analysis showed that the proportions of patients without AKI and without eGFR decline in the combination therapy group were significantly lower than those in the chemotherapy-alone group. Multivariate Cox regression analysis revealed that PD-1 inhibitor use and elevated baseline urea level were independent risk factors for eGFR decline; additionally, PD-1 inhibitor use was an independent risk factor for AKI occurrence (HR = 3.60, 95%CI 1.53–8.44). (3) The linear mixed model revealed that eGFR levels decreased in both groups during follow-up, with a statistically significant difference in the declining trend. The reduction was more pronounced in the combined treatment group (P = 0.018).

Conclusion: Compared with chemotherapy alone, the combined application of PD-1 inhibitors is significantly correlated with an increased risk of AKI and eGFR decline in tumor patients.

CLC Number: 

• R692.5

• R730.6

• R979.1