Association Between Hyperuricemia and Major Adverse Cardiac Events in Patients with Acute Myocardial Infarction.

BACKGROUND: To investigate the association between hyperuricemia and major adverse cardiac events (MACE) in patients with acute myocardial infarction (AMI).

METHODS: Consecutive patients admitted with AMI to the Coronary Care Unit at R. K. Khan Hospital (Durban, South Africa) between the years 2006 and 2014 were included. Demographic data, including clinical and biochemical information stored in an electronic database, were obtained from all patients.

RESULTS: A total of 2683 patients were studied, of whom 65% were males. The mean age of the participants was 57.1 ± 11.5 years, with 79% presenting with ST elevation myocardial infarction. Sixty-one percent were smokers, 59% had diabetes mellitus, 52% had hypertension, and 58% presented with a family history of premature coronary artery disease. Twenty-six percent (n = 690) had hyperuricemia, were older (59 ± 12.1 vs. 56.5 ± 11.2 years) and more likely to present with hypertension (P < 0.001), lower ejection fraction (P < 0.001), and higher median creatinine levels (P < 0.001). A significantly greater proportion of patients with hyperuricemia experienced MACE (45% vs. 30%, P < 0.001). In both sexes, considerable heterogeneity for risk factors and clinical events was noted in individuals with hyperuricemia. Multivariable analyses for risk factors associated with mortality suggest that hyperuricemia conferred a significantly increased risk of mortality after adjustment [odds ratio (OR) 1.7 (95% confidence interval 1.0-2.8); P = 0.042]. A significant increasing risk trend for MACE was observed for increasing tertiles of serum uric acid concentrations above normal (P < 0.001), particularly for cardiac failure (P < 0.001) and death (P = 0.006).

CONCLUSIONS: Hyperuricemia is significantly associated with hypertension, renal dysfunction, MACE, and independently confers a higher risk of mortality in patients with AMI. Significant heterogeneity was found by gender for risk factors and clinical events in individuals with hyperuricemia. A graded increase was demonstrated in the risk of MACE, particularly for cardiac failure and death, by increasing tertiles of hyperuricemia.