Abstract 4144822: Association between serum anion gap and short-term mortality in sepsis patients complicated by pulmonary hypertension: A cohort study based on MIMIC-IV database

Background: The relationship between anion gap (AG) and short-term mortality in intensive care unit (ICU) sepsis patients complicated by pulmonary hypertension (PH) remains unclear. Methods: Retrospective analysis of incident sepsis patients complicated by PH first admitted to ICU in MIMIC database (2008 to 2019) were enrolled. Short-term outcomes include in-hospital mortality and 28-day mortality. According to the AG value (17.0 mmol/L), patients were divided into high and low AG groups. The Kaplan-Meier survival curve was used to compare the cumulative survival rates of the high and low groups using the log-rank test. Multivariable Cox regression analyses were constructed to assess the relationship between AG and short-term outcomes in sepsis patients complicated by PH. Results: 2012 sepsis patients with pulmonary hypertension were included. The in-hospital mortality rates (11.4%) and 28-day mortality rates (12.8%) in the high AG group were higher than those in the low AG group (5.0% or 7.2%, respectively; P < 0.001). The Kaplan-Meier curve showed that the in-hospital and 28-day cumulative survival rates were lower in the high AG group than that in the low AG group ( P < 0.001). Multivariable Cox regression analysis confirmed that elevated AG was an independent risk factor of in-hospital mortality, 28-day mortality, length of stay in ICU and hospital. The relationship between elevated AG and in-hospital mortality remain stable after subgroups analyses. Conclusions: Elevated serum AG is associated with increased risk-adjusted short-term mortality in sepsis patients complicated by PH, and it may remind clinicians to identify patients with poor prognosis as early as possible.