High uric acid concentrations tied to hypertension
Higher concentrations of serum and urinary uric acid may predict higher 24-hour mean arterial pressure (MAP) and hypertension, a recent study suggests.
Researchers performed cross-sectional analysis in 2,555 individuals (mean age 60.0 years; 52 percent men; 27 percent had type 2 diabetes) from The Maastricht Study. They also conducted multivariable regression analyses to assess the association of serum uric acid concentration and 24-hour urinary uric acid excretion, as proxy for uric acid production, with ambulatory 24-hour blood pressure, 24-hour MAP and hypertension.
Serum uric acid concentration (per SD of 81 μmol/l) correlated with higher 24-hour MAP (β, 0.63 mm Hg; 95 percent CI, 0.27 to 1.00) and positively correlated with hypertension (odds ratio [OR], 1.43; 1.27 to 1.61) after adjustment for traditional hypertension risk factors. Urinary uric acid excretion (per SD of 140 mg/day/1.73 m2) was associated with higher 24-hour MAP (β, 0.79 mm Hg; 0.46 to 1.12) and with hypertension (OR, 1.13; 1.02 to 1.25).
Moreover, serum and 24-hour urinary uric acid excretion were not significantly correlated with 24-hour pulse pressure. No interaction with sex or age existed for the said associations.
“These results suggest that serum and 24-hour urinary uric acid concentrations, the latter as proxy for uric acid production are, independent of each other, associated with BP and hypertension,” according to researchers.
“Accumulation of reactive oxygen species by increased uric acid production has been suggested as a possible underlying mechanism for the association between uric acid and high blood pressure,” they added.
In The Maastricht Study, researchers did not find evidence supporting the hypothesis that generalized microvascular dysfunction was the underlying mechanism for the association between uric acid and cardiovascular and renal diseases. [J Hypertens 2015;33:1651-7]