Elevated levels of serum uric acid may increase the risk for cardiovascular (CV) mortality in patients with chronic kidney disease (CKD), according to a recent meta-analysis involving 11 studies published in BMC Nephrology.
In one part of the meta-analysis, Qimei Luo, MD, of the First Affiliated Hospital of Sun Yat-sen University in China, and colleagues examined 7 studies including 11,050 participants and found that patients with the highest levels of serum uric acid (SUA) had a significant 47% greater risk for CV death than those with the lowest uric acid (variably defined). A separate examination of 10 studies of 26,660 patients found that each 1 mg/dL increment in SUA was associated with a significant 12% increase in CV mortality risk.
This is the first meta-analysis looking at the association between uric acid with CV mortality in CKD patients, according to the study authors. In a discussion of possible mechanisms, they explained that hyperuricemia could interfere with mitochondrial function and promote oxidative stress. In addition, they noted that chronically high uric acid levels might spur inflammation or directly damage vessel walls. Elevated uric acid might also contribute to endothelial dysfunction and, in turn, hypertension and cardiovascular morbidity.
Among the study’s limitations, the team noted some heterogeneity, possibly related to varying definitions of CV mortality or participant characteristics. They were unable to perform subgroup analyses by CKD stage or patient sex.
Luo Q, Xia X, Li B, Lin Z, Yu X, Huang F. Serum uric acid and cardiovascular mortality in chronic kidney disease: a metaanalysis. BMC Nephrol. 20:18. DOI:10.1186/s12882-018-1143-7