Among patients with gout, treatment with at least 300 mg allopurinol daily was associated with a 13% reduced risk for kidney function decline, according to data published in JAMA Internal Medicine.
“There are no clear data to suggest that allopurinol is detrimental to renal function in patients with gout,” Ana Beatriz Vargas-Santos, MD, from the State University of Rio de Janeiro, and colleagues wrote. “Despite this, clinicians commonly hold or lower the dose of allopurinol or even discontinue allopurinol entirely when a patient with gout exhibits kidney function decline, leading to worse gout outcomes.”
Additionally, the researchers noted that “Although [chronic kidney disease (CKD)] is common in gout, most people with gout have normal kidney function, particularly early in the course of disease, yet there are limited data regarding renal effects of allopurinol among those with gout and normal kidney function.”
Among patients with gout, treatment with at least 300 mg allopurinol daily was associated with a 13% reduced risk for kidney function decline, according to data.
To evaluate the link between allopurinol use in gout and the risk for stage 3 or higher CKD, the researchers conducted a time-stratified propensity score–matched, population-based, prospective cohort study of patients with newly diagnosed gout who started allopurinol ( 300 mg daily) vs. patients who did not start allopurinol. Resulting data were analyzed using Cox proportional hazards regression.
Following screening, the researchers determined that 71% of all patients exhibited stage 2 CKD, while 29% exhibited stage 1 CKD or standard kidney function. Additionally, the use of medications was comparable among allopurinol users and nonusers, with 31% using diuretics and 73% using NSAIDs.
Vargas-Santos and colleagues then propensity score-matched 4,760 allopurinol users with 4,760 nonusers, excluding patients with stage 3 or higher CKD or urate-lowering therapy use prior to their gout diagnosis.
According to study findings, 579 allopurinol users developed stage 3 of higher CKD vs. 623 patients who did not use allopurinol, indicating that use of allopurinol of 300 mg or more daily was linked to lower risk for stage 3 or higher CKD compared with nonusers, with an HR of 0.87 (95% CI, 0.77-0.97). In addition, allopurinol initiation at less than 300 mg daily was not linked to renal function decline (HR = 1; 95% CI, 0.91-1.09).
“Allopurinol use, initiated at a dose of at least 300 mg/d, was associated with a 13% reduction in the risk of developing CKD stage 3 or higher,” Vargas-Santos and colleagues wrote. “In contrast, initiation of allopurinol at a dose of less than 300 mg/d had no association with developing CKD stage 3 or higher, consistent with current thinking that most patients need doses higher than 300 mg/d to achieve clinically meaningful outcomes.”
The researchers added, “Because allopurinol did not appear to be associated with renal function decline, clinicians should consider evaluating other factors when faced with renal function decline in their patients with gout rather than lowering the dose of or discontinuing allopurinol, a strategy that has contributed to the ongoing suboptimal treatment of gout.” – by Robert Stott
Disclosure: Vargas-Santos reports receiving speaker fees and international medical event support from Grünenthal. Please see the study for all other authors’ relevant financial disclosures.