Hyperuricemia and renal function.

Increased serum urate concentration is commonly seen in clinical practice. It does not represent a specific disease, nor is it an indication for therapy. Hyperuricemia can be the consequence of increased uric acid production and/or decreased renal capacity to excrete uric acid. In essential hypertension, it has been described in up to one third of patients and is directly related to an increase in renal vascular resistance and inversely correlated with renal plasma flow. In other words, abnormal renal hemodynamics, commonly seen in the initial stages of the disease, account for the increased serum urate concentration. This can be maintained if a decrease in glomerular filtration rate takes place. The increase in uric acid has been shown to be a potent predictor of the development of cardiovascular events and death. In addition, uric acid, particularly when elevated, could represent an independent risk factor. On the other hand, an altered renal function predicts in an independent manner a higher cardiovascular risk. For this reason, the predictive capacity of uric acid could be partly dependent on the fact that hyperuricemia runs in parallel with a deranged renal function.