Hyperuricemia and diabetes mellitus not only independently increase the risks for end-stage kidney disease (ESKD) and death, jointly they compound these risks, a new study finds.
As far as investigators are aware, the study is the first to demonstrate that hyperuricemia is a risk equivalent to diabetes mellitus for all-cause mortality and ESKD.
Among 4380 Taiwanese patients with stage 3 or higher chronic kidney disease (CKD), 40.5% had diabetes mellitus and 66.4% had hyperuricemia, including 26.8% who had both conditions. Hyperuricemia was defined as a serum uric acid level higher than 7 mg/dL in men and 6 mg/dL in women. Over 7 years of follow-up, 932 patients progressed to ESKD and 356 died.
In adjusted multivariate analyses, ESKD risk significantly increased 1.3-fold with hyperuricemia alone, 1.6-fold with diabetes alone, and 2.5-fold with both conditions compared with neither condition, Shang‑Feng Tsai, MD, of Taichung Veterans General hospital in Taiwan, and colleagues reported in BMC Nephrology. The risk for all-cause mortality significantly increased 1.5-fold with either hyperuricemia or diabetes alone and 2.1-fold with both conditions. These results were independent of traditional risk factors such as older age, male gender, hypertension, and smoking.
Potential mechanisms by which hyperuricemia could contribute to CKD progression include poorer renal perfusion via stimulation of afferent arteriolar vascular smooth muscle cell proliferation, the authors explained.
In addition, many conditions associated with hyperuricemia in patients with CKD could also contribute to CKD progression. The investigators pointed out, for example, that high serum uric acid levels may spur CKD progression in patients with type 2 diabetes.
Dr Tsai and colleagues could not gauge the use of some nephrotoxic medications, such as nonsteroidal anti-inflammatory drugs (NSAIDs), which is a study limitation.
Li CH, Lee CL, Hsieh YC, Chen CH, Wu MJ, Tsai SF. Hyperuricemia and diabetes mellitus when occurred together have higher risks than alone on all-cause mortality and end-stage renal disease in patients with chronic kidney disease. BMC Nephrol 23(1):157. Published online April 22, 2022. doi:10.1186/s12882-022-02755-1