Objectives: Hyperinflammatory and hypoinflammatory molecular subphenotypes in sepsis and acute respiratory distress syndrome have divergent mortality and treatment responses in secondary analyses of randomized controlled trials. However, the prevalence of immunocompromise is low in these populations, and how preexisting immunocompromise contributes to subphenotypes is unknown. We studied two observational sepsis cohorts to test associations between immunocompromise and the hyperinflammatory subphenotype and to assess whether the prognostic relevance of molecular subphenotypes is generalizable to immunocompromised populations. Design: Observational cohort study. Setting: Prospective data from two ICU cohorts in the United States. Patients: We included 1826 patients from two combined sepsis cohorts. Interventions: None. Measurements and Main Results: We defined immunocompromise as a history of solid organ transplant, AIDS, hematologic malignancy, solid malignancy on chemotherapy, or immunosuppressive medication use. Subphenotype was previously assigned using latent class analysis. We used logistic regression to investigate associations between type of immunocompromise and hyperinflammatory subphenotype. Models were repeated with individual covariates known or hypothesized to be associated with the hyperinflammatory subphenotype. Kaplan-Meier survival plots were used to assess mortality differences by subphenotype. Hematologic malignancy was strongly associated with the hyperinflammatory subphenotype (odds ratio OR, 4.3; p < 0.0001), an association that persisted after adjustment for identified pathogen, presence of bacteremia, or illness severity. History of solid organ transplantation was also associated with the hyperinflammatory subphenotype (OR, 1.6; p = 0.02) but was no longer significant after accounting for bacteremia. Hyperinflammatory classification was associated with a decreased likelihood of survival in hematologic malignancy, but not in organ transplant or solid malignancy populations. Conclusions: Preexisting immune status is associated with subphenotype assignment and may influence its prognostic utility.
Weingart et al. (Tue,) studied this question.