Abstract
Background
Diffuse large B-cell lymphoma (DLBCL) is the most common subtype of non-Hodgkin lymphoma and a frequent HIV-associated malignancy. Despite the widespread use of combination antiretroviral therapy, DLBCL remains a leading cause of morbidity and mortality among people living with HIV. However, the impact of HIV infection on lymphoma survival remains controversial, with some studies suggesting increased mortality (Han X et al, Cancer Epidemiol Biomarkers Prev. 2017) and others showing comparable outcomes (Coutinho R et al, AIDS. 2014). This study aimed to examine trends and evaluate the impact of HIV infection on in-patient mortality among patients with DLBCL, considering socioeconomic disparities.
Methods
We conducted a retrospective analysis using the National Inpatient Sample (NIS) database from 2016 to 2022. Using the International Classification of Diseases, 10th revision codes, adult admissions (age ≥18) with a primary diagnosis of DLBCL (ICD-10-CM C83.3) were identified and stratified by HIV status (ICD-10-CM B20, Z21). The primary outcomes were trends in the proportion of HIV-positive cases and hospitalization outcomes, including in-patient mortality, length of stay (LOS) and total hospital charges (THC). Secondary analyses included comparisons of epidemiologic and socioeconomic characteristics. Subgroup trend analyses were conducted by age (18–44, 45–64, ≥65), sex, race/ethnicity (White, African American, Hispanic, Others), income quartile, and insurance type. Multivariable logistic regression was used to assess the association between HIV status and in-patient mortality, adjusting for demographics, Elixhauser comorbidity index, hospital characteristics, and payer.
Results
Among 504,370 adult DLBCL admissions, 4.0% (n=20,010) were HIV-positive. Total DLBCL admissions increased from 66,165 in 2016 to 71,785 in 2022 (odds ratio (OR) 1.03, p<0.001), while the proportion of HIV-positive cases declined from 4.4% to 3.7% (p=0.024). Decreasing HIV-positive cases were seen among African Americans (20.3% to 15.2%, p=0.013), the lowest (7.1% to 6.2%, p=0.005) and highest income quartile (2.4% to 2.0%, p<0.001). No significant changes in HIV-positive cases were observed across other racial/ethnic or insurance subgroups.
Overall, in-patient mortality among DLBCL across 7 years was 4.9% (n=24,915). There was increasing trend in mortality from 4.3% in 2016 to 6.2% in 2022 (adjusted OR (aOR) 1.03, p<0.001), while mortality among HIV-positive DLBCL cases rose from 3.8% to 6.3% without a significant trend (p=0.546). There was no significant trend in mortality among subgroups of in both HIV-negative and HIV-positive DLBCL. Mean age increased in HIV-positive (47 vs 49 years, p<0.001) and HIV-negative DLBCL (64 vs 66 years, p<0.001). Among HIV-positive DLBCL, male (79.5% to 83.3%, p=0.013) and Hispanic population (19.4% to 27.7%, p=0.078) increased from 2016 to 2022. HIV-negative DLBCL showed increased LOS (7.3 vs 8.3 days, p<0.001) and THC ($116k vs $153k, p<0.001), whereas both remained comparable in HIV-positive DLBCL.
HIV-positive patients were significantly younger (mean age 47.7 vs 65.2 years, p<0.001) and more likely to be male (79.1% vs 56.7%, p<0.001), African American (39.4% vs 7.1%, p<0.001), or Hispanic (20.6% vs 10.2%, p<0.001) compared to HIV-negative patients. Predominant insurer among HIV-positive DLBCL were Medicaid (41.5%) and private insurance (32.9%), while Medicare predominated among HIV-negative patients (56.0%). Low-income status was more common in the HIV-positive group, with 40.9% in the lowest income quartile, in contrast to 21.2% in HIV-negative group.
Crude in-patient mortality did not differ significantly between groups (4.7% vs 5.0%, p=0.429). HIV status was not associated with increased adjusted in-patient mortality (aOR 1.05, p=0.616). HIV-positive DLBCL had longer LOS than HIV-negative group (8.9 vs 7.6 days, p<0.001) with comparable THC.
Conclusion
HIV-positive DLBCL patients demonstrate distinct demographic and socioeconomic characteristics, including younger age, male predominance, minority racial/ethnic groups, and lower income levels. Despite these differences, HIV status was not associated with increased in-patient mortality. These findings highlight the need for tailored clinical and public health approaches to address disparities and optimize care for DLBCL patients with HIV. Limitations include the retrospective design and lack of clinical details such as CD4 counts and lymphoma staging.
