Uric acid and risk of myocardial infarction. A dynamic duo

Uric acid is the final product of purine metabolism and its increase in the circulating blood defines the presence of hyperuricaemia commonly considered as a concentration of uric acid in serum bove the threshold level of 7 mg/dL (416 μmol/L) in men and N 6 mg/dL in women. The typical consequence of elevated uric acid levels is the onset of gout, a condition affecting 2–3% of the general population with a higher prevalence in patients with hypertension and metabolic abnormalities particularly when treated with diuretics. In the last 10 years a large number of papers have been published demonstrating a close relationship between elevated levels of uric acid and the relative risk of cardiovascular disease including coronary artery disease and myocardial infarction. An increase in the levels of serum urate is associated with atherosclerotic plaque instability as a consequence of a higher oxidised lipid content and a decrease in the thickness of the plaque fibrotic cap that are linearly related to serum uric acid levels. In particular a recent paper of our group has demonstrated that levels of serum uric acid in the “normal” range (N5.0 mg/dL in men or 4.5 mg/dL in postmenopausal women) can be associated with an increased incidence and mortality for myocardial infarction.