Reaching SUA goal in urate lowing therapy may improve glomerular filtration rate

WASHINGTON — Reaching target serum uric acid levels with urate-lowering therapy in chronic kidney disease was associated with improvement in the estimated glomerular filtration rate, according to findings presented at the American College of Rheumatology Annual Meeting.

Gerald D. Levy, MD, and colleagues conducted a retrospective cohort study to determine whether urate-lowering therapy can improve chronic kidney disease (CKD) function when patients reach a serum uric acid goal of less than 6mg/dL. They also aimed to determine whether baseline CKD stage influences the impact of urate lowering therapy.

Gerald D. Levy

After baseline assessment, patients also underwent an estimated glomerular filtration rate (eGFR) assessment in the 6 months before the index date, and at least one eGFR and a serum uric acid assessment between 3 months and 6 months after index. Patients were followed for a year. A 30% decrease or a 30% improvement in the eGFR from baseline served as the primary outcome measure.

The analysis included 12,751 patients. Data were presented for 2,690 patients who received urate-lowering therapy during the study period and 10,061 who did not.

The goal serum uric acid level was reached by 42% of patients who were treated with urate-lowering therapy. Among these patients who reached the goal, a 30% improvement in eGFR was observed in 17.1%. Conversely, a 30% improvement in eGFR was observed in 10.4% of patients who failed to reach the serum uric acid level goal.

“If you look at the whole cohort, it makes sense that the group that was given uric acid-lowering therapy improved in terms of GFR,” Levy said.

The researchers also conducted a pairwise comparison of CKD stages. Patients who were at or below the serum uric acid level goal were more likely to experience a 30% improvement in eGFR than those who did not reach the goal. In CKD2, 7.1% of patients who reached the goal experienced a 30% improvement compared with 3.3% among those who did not reach the goal. For CKD3, 19.9% of patients who reached the serum uric acid level goal and 10.0% of patients who did not experienced the 30% improvement in eGFR. For CKD4, 30.0% of patients who reached the goal and 22.2%% of patients who did not experienced the 30% improvement in eGFR.

“Among those who did not get worse, only the CKD3 showed any benefit. It is definitely the sweet spot,” Levy said. “CKD4 is probably too late.” – by Rob Volansky

Reference:

Levy GD, et al. Abstract #912. Presented at: The American College of Rheumatology Annual Meeting; Nov. 11-16, 2016. Washington.

Disclosure: Levy reports no relevant financial disclosures.