Transthyretin at Admission and Over Time as a Marker for Clinical Outcomes in Critically Ill Trauma Patients: A Prospective Single-Center Study

Haltmeier, Tobias; Inaba, Kenji; Durso, Joseph; Khan, Moazzam; Siboni, Stefano; Cheng, Vincent; Schnüriger, Beat; Benjamin, Elizabeth; Demetriades, Demetrios

BACKGROUND: Transthyretin (TTR) has been described as a predictor for outcomes in medical and surgical patients. However, the association of TTR on admission and over time on outcomes has not yet been prospectively assessed in trauma patients. METHODS: This is a prospective observational study including trauma patients admitted to the intensive care unit (ICU) of a large Level I trauma center 05/2014–05/2015. TTR levels at ICU admission and all subsequent values over time were recorded. Patients were observed for 28 days or until hospital discharge. The association of outcomes and TTR levels at admission and over time was assessed using multivariable regression and generalized estimating equation (GEE) analysis, respectively. RESULTS: A total of 237 patients with TTR obtained at admission were included, 69 of whom had repeated TTR measurements. Median age was 40.0 years and median ISS 16.0; 83.1% were male. Below-normal TTR levels at admission (41.8%) were independently associated with higher in-hospital mortality (p = 0.042), more infectious complications (p = 0.032), longer total hospital length of stay (LOS) (p = 0.013), and ICU LOS (p = 0.041). Higher TTR levels over time were independently associated with lower in-hospital mortality (p = 0.015), fewer infections complications (p = 0.028), shorter total hospital and ICU LOS (both p < 0.001), and fewer ventilator days (0.004). CONCLUSIONS: In critically ill trauma patients, below-normal TTR levels at admission were independently associated with worse outcomes and higher TTR levels over time with better outcomes, including lower in-hospital mortality, less infectious complications, shorter total hospital and ICU LOS, and fewer ventilator days. Based on these results, TTR may be considered as a prognostic marker in this patient population.