Inflammation Mediates the Relationship Between Serum Uric Acid and New-Onset Diabetes Risk in Patients with Coronary Heart Disease: Results from a Multicenter Cohort Study [Letter]

Inflammation Mediates the Relationship Between Serum Uric Acid and New-Onset Diabetes Risk in Patients with Coronary Heart Disease: Results from a Multicenter Cohort Study" by Song et al, published in 2026 in Diabetes, Metabolic Syndrome and Obesity. 1 This study explored the relationship between serum uric acid(SUA) and the risk of new-onset diabetes in patients with coronary heart disease(CHD) and found that inflammation partially mediates this relationship.The study design was rigorous, with a relatively large sample size, and has certain clinical significance.However, in addition to the limitations already mentioned by the authors in the discussion, I think the study still deserved attention in the following areas.First, the study did not adequately control for the potential impact of renal function on the relationship between serum uric acid and diabetes.The authors excluded patients with severe renal insufficiency in the methods but did not further adjust or stratify for the effects of mild renal abnormalities (eg, mild decrease in estimated glomerular filtration rate [eGFR]) on the results.Multiple studies have emphasized this issue.For example, a cross-sectional study in Peruvian patients with type 2 diabetes mellitus (T2DM) explicitly included eGFR as a covariate in adjustments and reported that abdominal obesity remained significantly associated with hyperuricemia. 2 Another meta-analysis, including eight randomized controlled trials (RCTs), found that the eGFR in the hyperuricemia group was significantly lower than that in the normal group, and the risk of diabetic nephropathy was increased, highlighting the need to control for the influence of renal function.3 Furthermore, a retrospective cohort study comparing SGLT2 inhibitors with allopurinol used eGFR as the primary outcome, demonstrating the importance of adequately controlling for renal function.4 These studies indicate that including and adjusting for eGFR in the methodology can effectively reduce confounding bias.Failure to adequately control for the confounding factor of renal function may lead to an overestimation of the association between SUA and diabetes.Second, the study did not report or discuss potential differences in SUA measurement methods or laboratory standards across centers.Although the study included five centers, it did not specify whether all centers used a unified SUA detection method or whether inter-center calibration was performed.Differences in laboratory detection methods may introduce systematic errors, affecting the comparability of SUA levels and the stability of results.Additionally, despite including five centers, the study did not conduct a center effect analysis or sensitivity analysis to assess the impact of different regions and healthcare environments on the relationship between SUA and diabetes.Variations in lifestyle, dietary habits, and medical resources across regions may influence SUA levels and diabetes incidence.