The prognostic value of postoperative blood glucose in non-diabetic patients with rheumatic heart disease

Background: Blood glucose (BG) is a risk factor of adverse prognosis in non-diabetic patients in several conditions. However, a limited number of studies were performed to explore the relationship between postoperative BG and adverse outcomes in non-diabetic patients with rheumatic heart disease (RHD) undergoing valve replacement surgery (VRS). Methods: We identified 1395 non-diabetic patients who diagnosed with having RHD, and underwent preoperative coronary angiography and at least one valve replacement. BG was measured at admission to the intensive care unit (ICU) after surgery. The association of postoperative BG level with in-hospital and one-year mortality was accordingly analyzed. Results: Included patients were stratified into four groups according to postoperative BG level’s (mmol/L) quartiles: Q1 (< 9.3 mmol/L, n=348), Q2 (9.3-10.9 mmol/L, n=354), Q3 (10.9-13.2 mmol/L, n=341), and Q4 (≥ 13.2 mmol/L, n=352). The in-hospital death (1.1% vs. 2.3% vs. 1.8% vs. 8.2%, P<0.001) and MACEs (2.0% vs. 3.1% vs. 2.6% vs. 9.7%, P<0.001) were significantly higher in the upper quartiles. Postoperative BG > 13.0 mmol/L was the best threshold for predicting in-hospital death (area under the curve (AUC) = 0.707, 95% confidence interval (CI): 0.634-0.780, P<0.001). Multivariate logistic regression analysis indicated that postoperative BG > 13.0 mmol/L was an independent predictor of in-hospital mortality (adjusted odds ratio (OR) = 3.418, 95% CI: 1.713–6.821, P<0.001). In addition, Kaplan–Meier curve analysis showed that the risk of one-year death was increased for a postoperative BG > 13.2 (log-rank = 32.762, P<0.001). Conclusion: Postoperative BG, as a routine test, could be served as a risk-stratified measure for non-diabetic patients with RHD.