ABSTRACT
Objective To explore whether albumin corrected anion gap (ACAG) is associated with long-term mortality of sepsis patients.Methods Adult patients with a diagnosis of sepsis within the first 24 hours (from December 2013 to December 2014) admitted to the intensive care unit (ICU) were included via the Sepsis database of West China Hospital Sichuan University. To record their long-term survival, patients were followed up by telephone interview one year after enrollment. ACAG was calculated according to the anion gap (AG) level within the first 24 hours admitted to ICU, and patients were divided into normal ACAG group (ACAG 12-20 mmol/L) and high ACAG group (ACAG > 20 mmol/L), and clinical characteristics and 1-year mortality were compared between groups. Patients were also divided into survivors and non-survivors according to the 1-year survival outcome, and multivariate logistic regression analysis was conducted to find independent risk factors for long-term mortality of sepsis patients.Results A total of 296 sepsis patients were enrolled in the study, with 191 (64.5%) in the high ACAG group and 105 (35.5%) in the normal ACAG group. There were no significant differences in age, gender, acute physiology and chronic health evaluation Ⅱ (APACHE Ⅱ), sequential organ failure assessment (SOFA), Charlson cormobidity index (CCI) and other background variables between groups. Compared with the normal ACAG group, patients who suffered from multiple organ dysfunction syndrome (MODS) in the high ACAG group were more prone to develop renal and gastrointestinal injury (43.5% vs. 25.7%, 52.9% vs. 33.3%, respectively), had significantly higher serum creatinine [SCr (μmol/L): 89.0 (61.0, 148.0) vs. 67.1 (48.0, 86.0)], greater need for continuous renal replacement therapy (CRRT, 16.8% vs. 6.7%), and significantly shorter length of ICU stay and hospital stay [days: 11 (5, 22) vs. 16 (18, 31), 21 (14, 39) vs. 28 (20, 47)], with statistically significant differences (allP < 0.05). It was shown by Kaplan-Meier survival analysis that 1-year cumulative survival for the high ACAG group was significantly lower than that of the normal ACAG group (55.0% vs. 67.7%,P = 0.046). It was shown by multivariate logistic regression that ACAG [odds ratio (OR) = 1.201, 95% confidence interval (95%CI) = 1.115-1.293,P = 0.000], APACHE Ⅱ (OR = 1.053, 95%CI = 1.011-1.098, P = 0.014), the incidence of septic shock (OR = 2.203, 95%CI = 1.245-3.898,P = 0.007), fungus infection (OR = 3.107, 95%CI = 1.702-5.674,P = 0.000), acute renal failure (OR = 2.729, 95%CI = 1.134-6.567,P = 0.025) and complicated with malignancy (OR = 2.929, 95%CI = 1.395-6.148,P = 0.005) were independent risk factors contributing to increased 1-year mortality among sepsis patients.Conclusion ACAG was an independent risk factor for 1-year mortality of sepsis patients.