The prognostic impact of rheumatoid arthritis in sepsis: a population-based analysis

Background: Rheumatoid arthritis (RA) is associated with increased risk of sepsis and higher infection-related mortality compared to the general population. However, the evidence on the prognostic impact of RA in sepsis has been inconclusive. We aimed to estimate the population-level association of RA with short-term mortality in sepsis. Methods: We used statewide data to identify hospitalizations aged >= 18 years in Texas with sepsis, with and without RA during 2014-2017. Hierarchical logistic models with propensity adjustment (primary model), propensity score matching, and multivariable logistic regression without propensity adjustment were used to estimate the association of RA with short-term mortality among sepsis hospitalizations. Results: Among 283,025 sepsis hospitalizations, 7,689 (2.7%) had RA. Compared to sepsis hospitalizations without RA, those with RA were older (aged >= 65 years, 63.9% vs. 56.4%) and had higher burden of comorbidities (mean Deyo comorbidity index, 3.2 vs. 2.7). Short-term mortality of sepsis hospitalizations with and without RA was 26.8% vs. 31.4%. Following adjustment for confounders, short-term mortality was lower among RA patients (adjusted odds ratio [aOR], 0.910; 95% confidence interval [CI], 0.856-0.967), with similar findings on alternative models. On sensitivity analyses, short-term mortality was lower in RA patients among sepsis hospitalizations aged >= 65 years and those with septic shock, but not among those admitted to intensive care unit (ICU; aOR, 0.990; 95% CI, 0.909-1.079). Conclusions: RA was associated, unexpectedly, with lower short-term mortality in septic patients. However, this "protective" association was driven by those patients without ICU admission. Further studies are warranted to confirm these findings and to examine the underlying mechanisms.