1199: ASSOCIATION OF SUBSTANCE USE DISORDERS WITH SHORT-TERM MORTALITY IN SEPSIS

Abstract

Introduction: Substance use disorders (SUD) are associated with increased risk of sepsis compared to the general population and may be expected to adversely affect sepsis outcomes. Recent studies have suggested lower risk of death among septic patients with opioid use disorder-related hospitalizations. However, the prognostic impact of the full spectrum of SUD, irrespective of its relationship to admission diagnoses, among septic patients has not been well-characterized. Methods: We used a statewide dataset to identify hospitalizations aged ≥18 years with sepsis in Texas during 2014-2017. Sepsis was defined by “explicit” ICD-9 and ICD-10 codes for severe sepsis (995.92, R65.20) and septic shock (785.52, R65.21). SUD was defined by the ICD code-based Clinical Classification Software category 661. A hierarchical, mixed-effects model was fit to estimate the association of SUD with short-term mortality (defined as in-hospital death or discharge to hospice) among sepsis hospitalizations. Sensitivity analyses of sepsis hospitalization aged ≥65 years, those with septic shock, and those with ICU admission were performed using similar modeling approach. Results: Among 283,025 sepsis hospitalizations, 22,789 (8.1%) had SUD. Compared to sepsis hospitalizations without SUD, those with SUD were younger (aged ≥65 years 32.7% vs 58.8%), less commonly racial/ethnic minority (46.4% vs 48.1%), and with lower burden chronic illness (mean [SD] Charlson Comorbidity Index (2.6 [2.5] vs 2.7 [2.4]) [p< 0.001 for all comparisons]. Short-term mortality among sepsis hospitalizations with and without SUD was 24.0% vs 31.9%. On adjusted analysis, SUD remained associated with lower risk of short-term mortality (adjusted odds ratio [aOR] 0.66 [95% CI 0.64-0.69]). The lower risk of short-term mortality in SUD patients remained on sensitivity analyses of sepsis hospitalizations aged ≥65 years (aOR 0.61 [95% CI 0.57-0.64]), those with septic shock (aOR 0.68 [95% CI 0.65-0.71]), and ICU admission (aOR 0.66 [95% CI 0.62-0.70]). Conclusions: SUD were associated, unexpectedly, with markedly lower risk of short-term mortality among sepsis hospitalizations, including older patients and across escalating illness severity. Further studies are needed to explore the mechanisms of the apparent “protective” association of SUD in sepsis.