Kidney outcomes in patients with bladder cancer: Insights from real-world data—A National Inpatient Sample (NIS) study, 2020.

e16622 Background: Bladder cancer constitutes a notable etiological factor in kidney disease, precipitating acute kidney injuries (AKI) through mechanisms such as post-renal obstruction, with the potential for progression to chronic kidney disease (CKD) over time. The objective of this study is to systematically evaluate the correlation between bladder cancer and the manifestation of acute or chronic kidney disease across various stages, with a focus on hospitalized patients undergoing treatment for bladder cancer. Methods: The 2020 United States National Inpatient Sample (NIS) database was subjected to analysis in this study. We focused on adult patients (≥18 years) with a primary discharge diagnosis of bladder cancer, specifically those who were hospitalized for cancer and presented with a diagnosis of acute kidney injury or diverse stages of chronic kidney disease, as identified through pertinent ICD-10 CM codes. Utilizing survey multivariable logistic and linear regression analysis, we calculated adjusted odds ratios (ORs) to assess the outcomes of interest. A p-value of <0.05 was deemed statistically significant in this analytical framework. Results: In 2020, 81,995 eligible patients were identified, with 75.62% being male. The ethnic distribution was 81% Caucasian, 8% Black, 5% Mexican American, and 2% Asian. Using a multivariable regression model adjusting for patient and hospital-level factors, bladder cancer showed a significant association with acute kidney injury (OR 1.92, 95% CI: 1.85-2.00, P < 0.001) and all stages of chronic kidney disease (OR 1.66, 95% CI: 1.58-1.74, P < 0.001). Further analysis revealed no significant association with early CKD stages 1 and 2 (P = 0.25 and 0.26), but a notable association with increased risk for CKD stages 3 and 4 (OR 1.45, 95% CI: 1.37-1.52, P < 0.001) and (OR 1.69, 95% CI: 1.56-1.83, P < 0.001), respectively. Intriguingly, bladder cancer displayed a negative association with CKD stage 5 (OR 0.76, 95% CI: 0.63-0.78, P < 0.001). Conclusions: In summary, our study reveals that bladder cancer in hospitalized cancer patients is linked to increased risks of acute kidney injury (AKI), CKD stages 3 and 4, and a decreased risk of CKD stage 5. Vigilant kidney function monitoring is crucial during cancer hospitalization, given the elevated risk of worsening function. Proactive interventions are necessary to address kidney-related complications. Further longitudinal cohort studies are warranted to enhance our understanding and devise strategies to reduce the risk of CKD in individuals with bladder cancer.