TNFR1 is associated with short-term mortality in patients with diabetes and acute dyspnea seeking care at the emergency department.

Background: Circulating levels of TNF alpha receptor 1 (TNFR1) and 2 (TNFR2) are associated with increased long-term mortality and impaired kidney function.
Aim: To study association between circulating levels of TNFR1 and TNFR2 and short-term mortality in patients with diabetes and dyspnea.
Population and Methods: Patients aged ≥ 18 years seeking at emergency department (ED) during daytime on weekdays between December 2013 and July 2018, with diabetes and acute dyspnea, identified at the triage process, were included. Participants (n = 291) were triaged according to Medical Emergency Triage and Treatment System-Adult score, and blood samples were collected. Association between TNFR1 and TNFR2, respectively, and 90-day mortality were estimated by Cox regression models adjusted for age, sex, BMI, creatinine and CRP.
Results: Univariate models showed significant associations between TNFR1 and TNFR2, respectively, and CRP, age and creatinine. TNFR1 and TNFR2 tended to be elevated in patients with the highest triage level, compared to patients with lower triage levels (ns). In longitudinal analyses, TNFR1 but not TNFR2 was associated with increased short-term mortality, HR adjusted for age, BMI and creatinine 1.43 (95% CI 1.07-1.91), but not in the model also adjusted for CRP, HR 1.29 (95% CI 0.94-1.77). In secondary analysis for quartile 4 versus quartiles 1-3 of TNFR1, corresponding HRs were 2.46 (95% CI 1.27-5.15) and 2.21 (95% CI 1.07-2.56).
Conclusions: We found a trend for the association between circulating TNFR1 levels and short-term mortality in patients with diabetes and acute dyspnea at the ED, possibly suggesting an inflammatory pathway for the association.