Kemal Ozan LÜLE, Soner BERŞE
European Journal of Therapeutics - 2026;32(3):366-375
Objective: Glycated hemoglobin (HbA1c) reflects long-term glycemic exposure; however, its relationship with renal function in non-diabetic adults has not been clearly defined. This study aimed to investigate the association between HbA1c levels and estimated glomerular filtration rate (eGFR) in a non-diabetic adult population. Methods: This retrospective cross-sectional study included 197 non-diabetic adults attending the internal medicine outpatient clinic of Gaziantep University Şahinbey Research and Practice Hospital. The estimated glomerular filtration rate was calculated from serum creatinine, and HbA1c levels were evaluated as both continuous and categorical variables. Associations between HbA1c and eGFR were analyzed using correlation and linear regression analyses with adjustment for age, sex, hypertension, and fasting plasma glucose. Results: HbA1c levels were inversely correlated with eGFR (Spearman rho = -0.237, p < 0.001). In univariate analysis, each 1% increase in HbA1c was associated with a 9.8 mL / min / 1.73 m² decrease in eGFR. Although this association was attenuated after adjustment for age, HbA1c remained independently associated with eGFR in the fully adjusted multivariable model (beta = -4.31, p = 0.042). Median eGFR values decreased across HbA1c categories, with the lowest values observed in participants with prediabetes. Conclusion: Higher HbA1c levels were independently associated with lower eGFR in non-diabetic adults. These findings suggest that HbA1c may reflect early renal vulnerability even below diagnostic thresholds for diabetes mellitus, warranting further investigation in prospective longitudinal studies.
