Impact of baseline lymphopenia on prognosis of patients with septic shock.

BACKGROUND: Sepsis is defined as life-threatening organ dysfunction due to a dysregulated host response to infection. Lymphocytes play an important role in sepsis, but little is known about the comparisons of different lymphopenia and non-lymphopenia patients with septic shock. The aim of this study is to compare the clinical characteristics of patients with septic shock among pre-existing lymphopenia group, sepsis-induced lymphopenia group, and non-lymphopenia group, and to identify the relationship of different lymphopenia with outcomes. METHODS: This retrospective study included 354 septic-shock patients with baseline lymphocyte available during 2013 and 2023, which were divided into pre-existing lymphopenia group, sepsis-induced lymphopenia group, and non-lymphopenia group. We compared the clinical characteristics and identified the relationship of different lymphopenia with 30-day mortality by univariate analysis and multivariable logistic regression analysis. RESULTS: Among 354 patients with septic shock with baseline lymphocyte available, the pre-existing lymphopenia group (n = 159) exhibited the highest 30-day mortality (50.9%), while the mortality in sepsis-induced lymphopenia patients (n = 143) and non-lymphopenia groups (n = 52) was 37.1% and 44.2%, respectively (p = 0.069). Multivariable analysis showed that pre-existing lymphopenia was an independent risk factor for 30-day mortality (OR 3.67, 95% CI 1.61–8.79), while lymphopenia at ICU admission was not (OR 0.95, 95% CI 0.28–3.37). CONCLUSION: Pre-existing lymphopenia was an independent risk factor for 30-day mortality in patients with septic shock, while sepsis-induced lymphopenia at ICU admission was not. These results suggest that historical lymphocyte count level should be incorporated into risk stratification paradigms for septic shock patients.