Type 2 diabetes mellitus (T2DM) outpatients, characterized by hyperglycemia, present challenges in managing glycemic control by glycated hemoglobin (HbA1c) and its connection to cardiometabolic and renal complications. These complications exacerbate insulin resistance, thereby affecting the reliability of HbA1c. There is a need for integrated management strategies to improve cardiovascular and renal outcomes of T2DM outpatients. This cross-sectional study investigates the link between HbA1c levels and both cardiometabolic and renal risk factors in T2DM outpatients. Univariate and multivariate analyses were conducted using linear regression within the generalized linear model (GLM) framework, applying a predefined HbA1c threshold of ≥7% (53 mmol/mol) as the cut-off of the dependent variable. Factors with no effect were eliminated by using an analysis of variance (ANOVA) test. The median of HbA1c was 7.4% [5.6% - 10.1%]. Multivariate analysis with continuous biological variables showed that fasting plasma glucose (FPG): OR, 1.4 (95% CI [1.2 - 1.7], p < 0.001); total cholesterol (TC): OR, 13.2 (95% CI [2.8 - 85.7], p = 0.002); estimated glomerular filtration rate chronic kidney disease epidemiology 2021 (eGFR-CKD-EPI 2021) creatinine-based formula: OR, 1.0 (95% CI [1.0 - 1.1], p = 0.03) and estimated glomerular filtration rate modification of diet in renal disease (eGFR-MDRD): OR, 1.0 (95% CI [1.0 - 1.0], p = 0.03) were positively associated with the likelihood of HbA1c ≥ 7%. In contrast, atherogenic index (AI): OR, 0.4 (95% CI [0.1 - 1.2], p = 0.11), body mass index (BMI) (18.5 - 25 Kg/m2): OR, 0.1 (95% CI [0.0 - 0.8], p = 0.052) and HDL cholesterol (HDL-C): OR, 0.0 (95% CI [0.0 - 0.5], p = 0.03) were negatively associated with HbA1c, but AI association was not significant. Categorical biological variables multivariate analysis highlighted that BMI (18.5 - 25 Kg/m2): OR, 0.1 (95% CI [0.0 - 0.6], p = 0.03), FPG (<7.15 mmol/L): OR, 0.1 (95% CI [0.0 - 0.2], p < 0.001) and Na+ (135 - 145 mmol/L): OR, 0.2 (95% CI [0.1 - 0.9], p = 0.03) were negatively associated with HbA1c ≥ 7%. Our findings highlight that the management of outpatients with T2DM requires a more holistic approach than merely evaluating HbA1c levels. Thus, it is essential to implement comprehensive strategies addressing cardiometabolic and renal factors that influence HbA1c variability.
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