Elevated preoperative suPAR is a strong and independent risk marker for postoperative complications in high-risk patients undergoing major non-cardiac surgery (SPARSE)

Background Patients undergoing major surgery are often at risk of developing postoperative complications. We investigated whether the inflammatory biomarker suPAR can aid in identifying patients at high risk for postoperative complications, morbidity, and mortality. Methods In this prospective observational study ( ClinicalTrials.gov identifier: NCT03851965 ), peripheral venous blood was collected from consecutive adult patients scheduled for major non-cardiac surgery with expected duration ≥2 hours under general anesthesia. Patients fulfilling the following inclusion criteria were included: age ≥18 years and American Society of Anesthesiologists’ physical status I to IV. Plasma suPAR levels were determined using the suPARnostic® quick triage lateral flow assay. The primary endpoint was post-operative complications defined as presence of any complication and/or admission to intensive care unit and/or mortality within the first 90 postoperative days. Results Preoperative suPAR had an OR of 1.50 (95%CI 1.24-1.82) for every ng/ml increase (AUC 0.82, 95%CI: 0.72-0.91). When including age, sex, ASA score, CRP, and grouped suPAR in multivariate analysis, patients with suPAR between 5.5 and 10 ng/ml had an OR of 12.7 (CI: 3.6-45.5) and patients with suPAR>10 ng/ml had an OR of 20.7 (CI: 4.5-95.4) compared to patients with suPAR≤5.5 ng/ml, respectively. ROC analysis including age, sex, CRP levels, and ASA score and had an AUC of 0.69 (95%CI: 0.58-0.80). When suPAR was added to this Model, the AUC increased to 0.84 (0.74-0.93) (p=0.009). Conclusions Preoperative suPAR provided strong and independent predictive value on postoperative complications in high-risk patients undergoing major non-cardiac surgery.