Troponin T levels predict early mortality following noncardiac surgery
MedWire News: Researchers have found that the peak postoperative troponin T measurement during the first 3 days after surgery is significantly associated with 30-day mortality.
"Although at present, troponin measurements are not commonly measured after noncardiac surgery, the simplicity of this test and its prognostic power suggest it may have substantial clinical utility," say Philip Devereaux (McMaster University, Hamilton, Ontario, Canada) and colleagues.
The researchers measured troponin T levels 6-12 hours after surgery and then on days 1, 2, and 3 among 15,133 patients aged 45 years and older who required at least an overnight hospital stay following noncardiac surgery.
A 30-day mortality rate of 1.9% was observed in the study, with 26.6% of patients dying following hospital discharge. The median number of days to death was 11.0 days for these patients.
In total, 11 of the 24 assessed variables were independent predictors for 30-day mortality, with urgent or emergency surgery the strongest preoperative predictor (adjusted hazard ratio [aHR]=4.62), followed by major neurosurgery (aHR=3.72), major general surgery (aHR=3.25), and active cancer (aHR=2.38).
Multivariate analysis showed that peak troponin T threshold values of at least 0.02 ng/mL, which occurred in 11.6% of patients, were associated with higher 30-day mortality compared with a peak value of 0.01 ng/mL or less.
Indeed, a peak troponin T value of 0.02 ng/mL increased the risk for 30-day mortality 2.41-fold, while values of 0.03-0.29 ng/mL and 0.30 ng/mL or greater increased this risk by 5.00- and 10.48-fold, respectively, relative to a peak value of 0.01 ng/mL.
Peak troponin T values of 0.01 ng/mL or less, 0.02, 0.03-0.29, and 0.30 ng/mL or greater occurred in 88.4%, 3.3%, 7.4%, and 0.9% of patients, respectively, with corresponding 30-day mortality rates of 1.0%, 4.0%, 9.3%, and 16.9%.
The average number of days to death for patients with troponin T values of 0.02, 0.03-0.29, and 0.30 ng/mL or above were 13.5, 9.0 and 6.5 days, respectively.
Writing in JAMA, Devereaux and team conclude: "There is now a need for large randomized controlled trials to evaluate potential interventions to mitigate the high risk of death in patients who have an elevated troponin measurement after noncardiac surgery."
By Ingrid Grasmo