Prognostic value of postoperative high-sensitivity troponin T in patients with different stages of kidney disease undergoing noncardiac surgery

Background Emerging evidence suggests that postoperative troponin release is a strong and independent predictor of short-term mortality. However, evaluating elevated troponins in patients with chronic kidney disease (CKD) is still controversial and is often disregarded. This study examines morbidity along with short- and long-term mortality risk associated with elevated high-sensitivity troponin T (hsTnT) in patients with different stages CKD undergoing noncardiac surgery.

Methods This observational cohort comprised 3262 patients aged ≥60 yr who underwent noncardiac surgery. Postoperative hsTnT concentrations were divided into normal [<14 ng l−1 (reference)], low (14–49 ng l−1), moderate (50–149 ng l−1), and high (≥150 ng l−1) groups. A threshold of 50 ng l−1 was used to dichotomize hsTnT. The study endpoints were 30-day and long-term all-cause mortality, and postoperative myocardial infarction.

Results Postoperative hsTnT was associated with a stepwise increase in 30-day and long-term mortality risk: low hsTnT adjusted hazard ratio (HR) 1.4 [95% confidence interval (CI): 1.1–1.7], moderate hsTnT adjusted HR 3.1 (95% CI: 2.3–4.3), high hsTnT adjusted HR 5.5 (95% CI: 3.6–8.4). Postoperative hsTnT ≥50 ng l−1 was associated with 30-day and long-term mortality risk for each stage of CKD. Elevated troponin concentrations in severe CKD (estimated glomerular filtration rate <30 mL min−1 1.73 m−2), however, did not predict short-term death.

Conclusions Elevated postoperative hsTnT is associated with a dose-dependent increase in 30-day and long-term mortality risk in each stage of CKD with an estimated glomerular filtration rate ≥30 ml min−1 1.73 m−2.