Evaluation on Prognostic Ability of Serum Uric Acid for Very Old Acute Coronary Syndrome Patients with Diabetes Mellitus: A Prospective Cohort Study

Abstract

Background This study sought to evaluate the prognostic power of serum uric acid (UA) in predicting adverse events of very old acute coronary syndrome (ACS) patients with diabetes mellitus (DM).Methods This analysis involved 718 ACS patients > 80 years old who were collected general clinical data and baseline blood biochemical indicators prospectively from January 2006 to December 2012, and these patients were classified into two groups based on DM, then followed up after discharge. Kaplan–Meier method was performed for major adverse cardiac events (MACE) rates and all-cause mortality. Multivariate Cox regression was performed to analyze the relationship between UA level and long-term clinical prognosis. Receiver operating characteristic (ROC) curve was analyzed to predict the cutoff value of UA of the very old ACS patients with DM.Results There were 242 and 476 patients in groups DM and non-DM(NDM) and the follow-up time after discharge was 40–120 months (median: 63 months; interquartile range: 51–74 months). The differences in all-cause mortality, cardiac mortality and MACE rates in DM and NDM patients between the control group were statistically significant (P = 0.001). All-cause mortality, cardiac mortality and MACE incidence in DM patients with moderate and high UA level were significantly higher than those in control group (P = 0.001). There were statistically significant differences in long-term survival rates among the ACS groups (P = 0.001), and long-term survival rates decreased significantly with the increase of UA level. UA (OR = 2.106, 95%CI = 1.244–3.568, P = 0.006) was found to be an independent risk factor for all-cause mortality and MACE in very old ACS patients with DM. The cutoff value of UA was 353.6 µmol/L (sensitivity: 67.4%; specificity: 65.7%). The elevation of serum UA level play an important role in predicting the development of all-cause mortality in elderly ACS patients with DM.Conclusion Serum UA level is a strong independent predictor of long-term all-cause death and MACE in very old ACS patients with DM.