RIDGELAND, MS — Higher serum rate levels (sUA) are associated with an increased risk of incident kidney disease among veterans with gouty arthritis, according to a study based on records from a database at the VA’s VISN 16.
The study, published this past summer in the Journal of Rheumatology, sought to resolve conflicting evidence from epidemiologic research regarding the causal linkage between sUA concentration and the incidence and progression of chronic kidney disease.1
Between 30% and 60% of patients with gout exhibit a decrease in renal function over time, according to background in the article, and recent research has indicated that about 39% of patients with gout had chronic kidney disease as defined by estimated glomerular filtration rate < 90 ml/min/1.73 m2.
For this study, researchers identified adult male patients with gout who were free of kidney disease from 2002 through 2011 in the database and followed them until incidence of kidney disease, death or the last available observation. The 2,116 subjects were majority white (53%), an average of 62.6 years old and had mean body mass index of 31.2 kg/m2 and high baseline prevalence of hypertension (93%), hyperlipidemia (67%) and diabetes (20%).
Follow-up lasted an average of 6.5 years. Accumulated hazard curves for time to kidney disease were estimated for patients with average sUA levels > 7 mg/dl (high) vs. ≤ 7 mg/dl (low).
Results indicated that estimated rates of all incident kidney disease in the overall low vs. high sUA groups were 2% vs. 4% at Year 1, 3% vs. 6% at Year 2, and 5% vs. 9% at Year 3, respectively. After adjustment, high sUA continued to predict a significantly higher risk of kidney disease development (HR 1.43, 95% CI 1.20–1.70).
“The relationship between sUA concentration and kidney disease requires further clarification and has not been studied extensively within gout-specific populations,” according to the authors. “Risks of hyperuricemia and renal impairment are high among patients with gout; thus, it is important to understand the implications of sUA control in this disease area.”1
- Krishnan E, Akhras KS, Sharma H, Marynchenko M, Wu E, Tawk RH, Liu J, Shi L. Serum urate and incidence of kidney disease among veterans with gout. J Rheumatol. 2013 Jul; 40(7):1166-72. doi: 10.3899/jrheum.121061. Epub 2013 May 15.