Outcomes and Trends of Allogenic Hematopoietic Stem Cell Transplant Among MDS Patients- NIS 2016-2020

Background: This study aims to analyze the outcomes and trends of allogeneic hematopoietic stem cell transplantation (HSCT) in patients with Myelodysplastic Syndromes (MDS) using data from the National Inpatient Sample (NIS) from 2016 to 2020. The focus is on comparing in-hospital outcomes between MDS patients and non-MDS patients undergoing allogeneic HSCT. We also explore trends in the proportion of patients in the MDS population receiving HSCT from 2016 to 2020. Methods: The National Inpatient Sample (NIS) databases (2016-2020) of the Healthcare Cost and Utilization Project (HCUP) were used. ICD-10 codes were used to code for allogeneic HSCT, MDS, comorbidities and hospitalization outcomes. The Institutional Review Board (IRB) approval was not mandatory since the NIS contains deidentified data. We applied the discharge weight (DISCWT) provided in the database to generate the national estimates. Pearson Chi-square test for categorical variables and Student's t-tests/one-way ANOVA for continuous variables were applied to compare the baseline demographics and hospital characteristics between the two groups. Multivariate logistic regression analysis was carried after adjusting for demographic variables and comorbidities to obtain adjusted odds ratio (aOR) for hospitalization outcomes. Results: MDS patients (N=4980) were generally older (median age 62 years) compared to patients without MDS (median age 49 years). MDS patients had a higher proportion of Whites (80.66%) and a lower proportion of African-Americans (4.34%) and Hispanics (7.03%). Comorbid conditions such as chronic lung disease, diabetes mellitus, hypothyroidism, and hypertension were more prevalent in MDS patients (p<.001). Adjusted odds ratios indicated that MDS patients had a significantly higher risk of in-hospital mortality (aOR 1.33, 95% CI 1.14-1.55, p=0.0002), mechanical ventilation (aOR 1.30, 95% CI 1.12-1.51, p=0.0004), acute GVHD (aOR 1.26, 95% CI 1.11-1.43, p=0.0004) and neutropenic fever (aOR 1.20, 95% CI 1.12-1.28, p<0.001). Conversely, the risk of Clostridium difficile infection was lower (aOR 0.75, 95% CI 0.66-0.86, p<0.001). There was no statistically significant difference in the occurrence of VTE/PE and AKI between the two groups. The data from 2016 to 2020 indicate a steady increase in the proportion of allogeneic hematopoietic stem cell transplants performed on patients with Myelodysplastic Syndromes (MDS). In 2016, MDS patients accounted for 13.20% (200) of these transplants, which rose to 17.32% (1330) in 2019 before slightly declining to 16.42% (1160) in 2020. This decline in 2020 might have been due to the COVID-19 pandemic. Conclusion: MDS patients undergoing allogenic HSCT are older and have a higher burden of comorbidities compared to non-MDS patients. Despite advancements in supportive care, MDS patients experience higher in-hospital mortality and complications such as mechanical ventilation and neutropenic fever. The increasing trend in HSCT utilization among MDS patients is promising and underscores the need for continued improvements in patient selection and peri-transplant care to enhance outcomes. Further research is warranted to explore strategies to mitigate the risks associated with HSCT in this vulnerable population.