Association between decreases in serum uric acid levels and unfavorable outcomes after ischemic stroke: A multicenter hospital-based observational study

Background The association between clinical outcomes in ischemic stroke patients and decreases in serum uric acid levels, which often occur during the acute phase, remains unknown. Herein, we aimed to investigate the association using a large-scale, multicenter stroke registry. Methods We analyzed 4,621 acute ischemic stroke patients enrolled in the Fukuoka Stroke Registry between June 2007 and September 2019 whose uric acid levels were measured at least twice during hospitalization (including on admission). The study outcomes were poor functional outcome (modified Rankin Scale score ≥3) and functional dependence (modified Rankin Scale score 3–5) at 3 months after stroke onset. Changes in uric acid levels after admission were evaluated using a decrease rate that was classified into 4 sex-specific grades ranging from G1 (no change/increase after admission) to G4 (most decreased). Multivariable logistic regression analyses were used to assess the associations between decreases in uric acid levels and the outcomes. Results The frequencies of the poor functional outcome and functional dependence were lowest in G1 and highest in G4. The odds ratios (95% confidence intervals) of G4 were significantly higher for poor functional outcome (2.66 [2.05–3.44]) and functional dependence (2.61 [2.00–3.42]) when compared with G1 after adjusting for confounding factors. We observed no heterogeneity in results for subgroups categorized according to age, sex, stroke subtype, neurological severity, chronic kidney disease, or uric acid level on admission. Conclusions Decreases in serum uric acid levels were independently associated with unfavorable outcomes after acute ischemic stroke.