Serum creatinine is more strongly associated with hyperuricemia than eGFR in males but not in females.

Objectives: Serum creatinine and estimated glomerular filtration ratio (eGFR) are factors associated with hyperuricemia, though which is more closely associated with hyperuricemia remains unclear.

Subjects and methods: This retrospective cross-sectional study examined the associations of serum creatinine and eGFR with hyperuricemia using health check-up findings. Enrolled were 6020 individuals (3509 males, 2511 females) who underwent health check-ups from 2017 to 2021. The subjects were divided based on serum uric acid level into the normuricemia (males 1.5-7.0 mg/dl, females 1.5-< 6.0 mg/dl) and hyperuricemia (males >7.0 mg/dl, female ≥ 6.0 mg/dl) groups. Matched-pair analysis was used to evaluate the association between hyperuricemia and variables related to serum uric acid.

Results: Matched-pair analysis results showed a significant association of serum creatinine with hyperuricemia in male subjects but not in females. Furthermore, propensity score obtained by binominal logistic regression demonstrated that serum creatinine had a greater association with hyperuricemia than eGFR in the males but not in females.

Conclusions: The present findings indicate an association of serum creatinine with hyperuricemia in males not only because of reduced renal function but other factors related to greater muscle mass, such as increased intake of protein-rich foods containing purines and increased uric acid production induced by accelerated creatinine metabolism.