Association between Troponin I Levels during Sepsis and Postsepsis Cardiovascular Complications

Abstract

Rationale: Sepsis commonly results in elevated serum troponin levels and increased risk for postsepsis cardiovascular complications; however, the association between troponin levels during sepsis and cardiovascular complications after sepsis is unclear.Objectives: To evaluate the association between serum troponin levels during sepsis and 1 year after sepsis cardiovascular events.Methods: We analyzed adults aged ⩾40 years without preexisting cardiovascular disease within 5 years, admitted with sepsis across 21 hospitals from 2011 to 2017. Peak serum troponin I levels during sepsis were grouped as normal (⩽0.04 ng/ml) or tertiles of abnormal (>0.04 to ⩽0.09 ng/ml, >0.09 to ⩽0.42 ng/ml, or >0.42 ng/ml). Multivariable adjusted cause-specific Cox proportional hazards models with death as a competing risk were used to assess associations between peak troponin I levels and a composite cardiovascular outcome (atherosclerotic cardiovascular disease, atrial fibrillation, and heart failure) in the year following sepsis. Models were adjusted for presepsis and intrasepsis factors considered potential confounders.Measurements and Main Results: Among 14,046 eligible adults with troponin I measured, 2,012 (14.3%) experienced the composite cardiovascular outcome, including 832 (10.9%) patients with normal troponin levels, as compared with 370 (17.3%), 376 (17.6%), and 434 (20.3%) patients within each sequential abnormal troponin tertile, respectively (P < 0.001). Patients within the elevated troponin tertiles had increased risks of adverse cardiovascular events (adjusted hazard ratio [aHR]_{troponin0.04-0.09} = 1.37; 95% confidence interval [CI], 1.20-1.55; aHR_{troponin0.09-0.42} = 1.44; 95% CI, 1.27-1.63; and aHR_{troponin>0.42} = 1.77; 95% CI, 1.56-2.00).Conclusions: Among patients without preexisting cardiovascular disease, troponin elevation during sepsis identified patients at increased risk for postsepsis cardiovascular complications. Strategies to mitigate cardiovascular complications among this high-risk subset of patients are warranted.

Keywords: cardiovascular risk; infection; mortality; sepsis; troponin.

Figure 1.

Cohort assembly of adults without preexisting cardiovascular disease who survived sepsis hospitalization. A flow diagram identifying the cohort used in our primary analysis is shown. We identified a cohort of adults aged ⩾40 years without a prior diagnosis of cardiovascular disease who survived sepsis admission and had troponin I measured during their hospitalization.

Figure 2.

Multivariable association between peak troponin I level during sepsis and postdischarge risks of cardiovascular events (CVE) and all-cause death. Each circle represents a category of peak troponin I elevation during a hospitalization for sepsis and shows the adjusted hazard ratio (and associated 95% confidence interval) of that troponin I level and the outcome of interest. The blue line represents the adjusted hazards of a composite cardiovascular complication (atherosclerotic cardiovascular disease, atrial fibrillation, or heart failure), and the orange line represents the adjusted hazards of mortality at 1 year after discharge from a sepsis hospitalization. Modest troponin elevation was associated with a 37–77% increased risk of the composite outcome of CVE without an increased risk of mortality.

Figure 3.

Multivariable association between peak troponin I level during sepsis and postdischarge risks of individual types of cardiovascular events. Each circle represents a category of peak troponin I elevation during a hospitalization for sepsis and shows the adjusted hazard ratio (and associated 95% confidence interval) of that troponin I level and an individual cardiovascular complication at 1 year after discharge. The blue line represents the adjusted hazards of atherosclerotic cardiovascular disease (ASCVD), the orange line the adjusted hazards of atrial fibrillation, and the gray line the adjusted hazards of heart failure. Modest troponin elevation was associated with increased risks of each individual cardiovascular complication, most pronounced in ASCVD and heart failure events.