Associations between CRP/lymphocyte ratio, blood sugar regulation and other metabolic parameters in patients wi̇th type 2 diabetes mellitus

İntroduction: Type 2 Diabetes Mellitus (T2DM) has become a growing global epidemic far beyond predictions. The etiopathogenesis relationship between T2DM and low-grade inflammation is a new and important issue, and many biomarkers are being investigated to determine this relationship. CRP/Lymphocyte ratio (CLR) is an easily accessible and inexpensive inflammatory marker. CLR has been shown to be an effective predictor in diseases characterized by chronic, low-grade inflammation. Therefore, in our study, we aimed to examine the relationship between CLR and T2DM and blood sugar regulation in T2DM. Material-Method: Patients with T2DM who presented to Internal Medicine outpatient clinics of Bolu Abant İzzet Baysal University hospital between March 2022 and August 2022 were included to the study. Sociodemographic characteristics, laboratory parameters and anthropometric measurements of the patients were recorded. Patients with T2DM were divided into 2 groups according to their glycosylated hemoglobin (HbA1c) levels as well-controlled (HbA1c<7%) and poorly controlled (HbA1c≥7%) DM. In the control group, people over the age of 18 without any chronic disease were included. CLR was calculated by dividing the CRP value by the number of lymphocytes. The general characteristics, laboratory parameters and CLR values of the well and poorly controlled case group with T2DM and the control group were compared. Results: 385 patients were included in our study. Study groups were determined as 113 healthy controls without any disease and 272 T2DM patients. The CLR value of type 2 diabetes patients (3.51 (0.03-21.78)) was significantly higher than that of the control group (0.65 (0.02-2.92)) (p<0.001). A significant positive correlation was found between CLR and HbA1c, glucose, creatinine, spot urine protein/creatinine and spot urine microalbumin/creatinine ratio in patients. CLR value of 2.1998 and above was found to have a sensitivity of 63.2% and a specificity of 97.3% in predicting T2DM (AUC: 0.823; p<0.001; 95% CI: 0.784-0.863). The CLR value of patients with poor diabetic control (n=171) was 4.76 (0.06-21.78), while the CLR value of patients with good diabetic control (n=101) was 2.53 (0.03-12.07) (p<0.001). The sensitivity and specificity of the CLR value of 6.123 and above in demonstrating poor diabetic control was 41.2% and the specificity was 86.1% (AUC: 0.648; p<0.001; 95%CI: 0.583-0.714). Increased CLR is an independent risk factor for poor diabetic control (p<0.001; OR: 1.139; 95% CI: 1.039-1.250). Conclusions: A number of facts including, high sensitivity and high specificity of CLR in predicting T2DM, high specificity and moderate sensitivity of CLR in distinguishing poorly controlled T2DM from well-controlled T2DM, its significant correlation with serum creatinine, spot urine protein/creatinine, spot urine microalbumin/creatinine suggest that CLR can be used as a diagnostic and prognostic biomarker for T2DM.