Can high uric acid levels be an indicator of changes in kidney function?
Recent studies have shown a link between high uric acid levels and the development of CKD in diabetes patients with preserved renal function. To date, no studies have looked at regression of CKD as well as progression of CKD. This study aims to investigate the exact link between serum uric acid levels and CKD progression or regression in diabetes patients. Previous studies showed a link between high uric acid levels and the development of CKD in patients who did not previously have impaired renal function. It has been suggested to use uric acid levels as a diagnostic tool to indicate the worsening of renal function in diabetes patients. Using uric acid levels as a diagnostic tool could act as a warning for patients to try to make a change before they develop CKD.
This study followed a total of 2,367 type 2 diabetes patients from a specialized outpatient clinic for at least three years. Patients were divided into 3 groups (stable, progression and regression) based upon their change in CKD stage. Patients were excluded from the study if they were known to have urologic disease, if they were taking allopurinol or uricosuric agents, or if they underwent any contrast examination during the follow-up period. Baseline lab panels were drawn upon enrollment that included serum uric acid levels, A1C, lipid panel and serum creatinine (SCr). Patients were then seen every three months to measure blood pressure, weight, A1C and uric acid levels. Renal function (eGFR) was estimated using the 4 variable Modification of Diet in Renal Disease (MDRD) equation. Albuminuria was measured using the albumin-creatinine ratio. Albuminuria was defined by at least two measurements of albumin-creatinine ratio >30 mg/g in a 6-month period. Patients were assigned to the stable group if their CKD stage remained the same from baseline to the conclusion of the study. Patients were assigned to the progression group if their CKD stage worsened from baseline to the conclusion of the study. Patients were assigned to the regression group if their CKD stage improved from baseline to the conclusion of the study.
Once follow-up was completed, data analysis was done to assess mean uric acid levels between the groups. Baseline patient characteristics were assessed for similarity using the ANOVA and Chi-square tests. Then cox regression analysis was used to assess the variables that predicted the development of CKD. Results of this study showed that higher uric acid levels (6.9 ± 1.8 mg/dL) led to progression of CKD, confirming previous studies’ results. Of note, patients with lower uric acid levels (5.4 ± 1.5 mg/dL) showed regression of CKD staging. In addition, it was found that a serum uric acid level of >6.3 mg/dL was an independent factor associated with the progression of CKD.
This study proved that uric acid levels can be used as an indicator for the progression of CKD, as well as for the development of CKD as other studies have shown. With this being said, the argument can be made to use uric acid levels as a diagnostic tool when treating diabetes patients, with or without CKD. It is also recommended by this study that lower uric acid levels may be beneficial for stage 3-5 CKD patients to attempt to improve their CKD.
- Serum uric acid levels should be monitored in all diabetes patients as a part of their yearly laboratory testing.
- Higher uric acid levels (6.9 ± 1.8 mg/dL) can lead to the progression of CKD staging; conversely, lower uric acid levels (5.4 ± 1.5 mg/dL) can aid in the regression of CKD staging.
- A serum uric acid level of >6.3 mg/dL is an independent factor associated with progression of CKD.
Researched and prepared by Jennifer Zahn, Doctor of Pharmacy Candidate University Of South Florida College of Pharmacy, reviewed by Dave Joffe, BSPharm, CDE
Chang Y, Lei C, Lin K, Hsieh C, Lee Y. Serum uric acid level as an indicator for CKD regression and progression in patients with type 2 diabetes mellitus—a 4.6-year cohort study. Diabetes Metab Res Rev. Published online in Wiley Online Library (wileyonlinelibrary.com) DOI: 10.1002/dmrr.2768.