Linda H. Ficociello , DSC 1 , 2 , Elizabeth T. Rosolowsky , MD, MPH 1 , 3 , 4 , Monika A. Niewczas , MD, PHD 1 , 4 , Nicholas J. Maselli , BA 1 , Janice M. Weinberg , SCD 2 , Ann Aschengrau , SCD 2 , John H. Eckfeldt , MD, PHD 5 , Robert C. Stanton , MD 1 , 4 , Andrzej T. Galecki , MD, PHD 6 , Alessandro Doria , MD, PHD, MPH 1 , 4 , James H. Warram , MD, SCD 1 , Andrzej S. Krolewski , MD, PHD 1 , 4
23 March 2010
We previously described a cross-sectional association between serum uric acid and reduced glomerular filtration rate (GFR) in nonproteinuric patients with type 1 diabetes. Here, we prospectively investigated whether baseline uric acid impacts the risk of early progressive renal function loss (early GFR loss) in these patients.
Patients with elevated urinary albumin excretion ( n = 355) were followed for 4–6 years for changes in urinary albumin excretion and GFR. The changes were estimated by multiple determinations of albumin-to-creatinine ratios (ACRs) and serum cystatin C (GFRcystatin).
At baseline, the medians (25th–75th percentiles) for uric acid, ACR, and GFRcystatin values were 4.6 mg/dl (3.8–5.4), 26.2 mg/g (15.1–56.0), and 129 ml/min per 1.73 m 2 (111–145), respectively. During the 6-year follow-up, significant association ( P < 0.0002) was observed between serum uric acid and development of early GFR loss, defined as GFRcystatin decline exceeding 3.3% per year. In baseline uric acid concentration categories (in mg/dl: <3.0, 3.0–3.9, 4.0–4.9, 5.0–5.9, and ≥6), the risk of early GFR loss increased linearly (9, 13, 20, 29, and 36%, respectively). This linear increase corresponds to odds ratio 1.4 (95% CI 1.1–1.8) per 1 mg/dl increase of uric acid. The progression and regression of urinary albumin excretion were not associated with uric acid.
Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered. See http://creativecommons.org/licenses/by-nc-nd/3.0/ for details.