Changes in Serum Uric Acid After Laparoscopic Sleeve Gastrectomy: Are They Associated with Baseline Renal Hyperfiltration?

Laparoscopic sleeve gastrectomy (LSG) provides durable, stable weight loss and ameliorates renal dysfunction, hyperuricemia (HUA), and other obesity-related metabolic disorders. Renal function is tightly linked to serum uric acid (SUA) metabolism, but conventional estimated glomerular filtration rate (eGFR) equations have well-documented substantial bias in individuals with obesity.

We retrospectively collected clinical data from 202 patients who underwent LSG, with assessments performed at baseline and 1, 3, and 6 months postoperatively. Patients were stratified into the renal hyperfiltration (HF, 1n = 147) and normal filtration (NF, n = 55) groups using a baseline eGFR cutoff of 125 mL/min/1.73 m². 1:1 propensity score matching (PSM) was conducted using 7 covariates to balance baseline between-group heterogeneity.

The main effect of time on SUA levels was marginally significant pre-PSM (P = 0.054), but reached statistical significance post-PSM (P = 0.034). A significant main effect of group was observed at both stages (pre-PSM P = 0.008; post-PSM P = 0.037), with consistently higher SUA levels in the NF group. No significant time-by-group interaction effect was detected in either pre- or post-PSM analyses (both P > 0.05). Bonferroni-adjusted post hoc pairwise comparisons revealed significant SUA reductions at 3 and 6 months postoperatively relative to baseline in the pre-PSM HF group, with no significant temporal changes in the pre-PSM NF group; no significant pairwise differences across time points were seen in the matched cohort.

Temporal changes in SUA levels after LSG are not significantly associated with baseline renal filtration status.

• The time-by-group interaction effect was not significant in either pre- or post-PSM analyses, meaning the temporal trends of SUA levels after LSG did not differ significantly by baseline renal filtration status (HF vs. NF).

• Both before and after PSM, SUA levels were consistently lower in the HF group than in the NF group; therefore, a longer duration of SUA monitoring may be necessary for the NF group.