Evolving burden of acute kidney injury in non-Hodgkin's lymphoma hospitalizations: A seven-year nationwide study

Abstract Background: Acute Kidney Injury (AKI) is a significant complication among hospitalized patients with Non-Hodgkin's Lymphoma (NHL). NHL is a heterogeneous group of lymphoid malignancies that require complex treatment strategies such as chemotherapy, immunotherapy, and stem cell transplantation. These therapies in addition to disease associated factors such as tumor lysis syndrome and sepsis, make NHL patients vulnerable to renal injury. While prior studies have evaluated AKI in general cancer populations, specific epidemiological data focused on NHL patients remain significantly limited. It is essential to comprehend the burden, predictors and consequences of AKI in this group, in order to improve survival, guide inpatient therapy and decrease mortality. Methods: We included the National Inpatient Sample (NIS) database from 2016 and 2022 to identify adult hospitalizations with a primary diagnosis of NHL. Patients were divided into two groups based on the presence or absence of AKI. Demographics, comorbidities, and clinical outcomes were compared between both groups. Key outcomes included in-hospital mortality, in-hospital complications, length of stay (LOS), and total hospitalization charges. To account for confounding variables and compute adjusted odds ratios (aOR), multivariable logistic and linear regression models were utilized. All analysis was performed using Stata Version 17.0. Results: Out of 260,210 hospitalizations related to Non-Hodgkin's Lymphoma (NHL), 23% (n = 61,165) were associated with Acute Kidney Injury (AKI). Patients with AKI were observed to be older (mean age 68.1 vs. 62.3 years), more were male (64% vs. 57%), and had a greater Charlson Comorbidity Index Score, with 16% having a score of seven or more, compared to 7% in those without AKI. AKI was linked to significantly worse clinical outcomes, including a higher in hospital mortality rate (16% vs. 3.0%; adjusted odds ratio [aOR] 4.71; 95% confidence interval [CI]: 4.28–5.19), longer hospital stays (13.92 vs 9.51 days), and significantly higher hospital charges (adjusted difference of $77,487). Routine discharge rates were lower among AKI patients (37% vs. 62%), with significantly higher patients requiring skilled nursing or home health services. Several in-hospital complications showed a strong relation in NHL patients with AKI. These included tumor lysis syndrome (aOR: 8.98), sepsis (aOR: 4.52), liver failure (aOR: 4.15), and electrolyte or pH disorders (aOR: 3.62). Moreover, between 2016 and 2022 the frequency of AKI among NHL hospitalizations increased from 21.2 to 25.7 per 10,000 , showing a significant upward trend (average annual percent change [AAPC]: 2.83%, p < 0.001). Conclusion: Between 2016 and 2022, nearly one in four hospitalized patients with Non-Hodgkin's Lymphoma developed AKI, a complication that led to worse clinical and economic outcomes. Patients who developed AKI were generally older, male, and had a greater incidence of certain in-hospital complications. The rising frequency of AKI in this population highlights the growing need for advancement in AKI management and diagnostic tools for early detection.