Background: Neutrophil to lymphocyte ratio (NLR) and platelet to lymphocyte ratio (PLR) are inflammatory markers used for prediction of chronic complications of diabetes. Lower extremity arterial disease (LEAD) is one of chronic complications of type 2 diabetes mellitus (T2DM). The correlation between NLR, PLR, and lower extremity vascular lesions was investigated in subjects with T2DM to determine the best predictive marker for LEAD.
Methods: Three hundred thirty-five patients with T2DM (199 males and 136 females; age 54.12 ± 14.07 years) were enrolled. Blood differential counts and anklebrachial index (ABI) were assessed. Patients were divided into the LEAD group (ABI ≤ 0.9, n = 236) and non-LEAD group (ABI > 0.9, n = 99), and NLR and PLR were compared between the two groups. The independent risk factors for LEAD were analyzed using a logistic regression model. Receiver operating characteristic (ROC) curve analysis was used to assess the optimal cutoff values of PLR and NLR for prediction of LEAD.
Results: NLR and PLR in the LEAD group were significantly increased compared to non-LEAD group patients. Univariate analyses identified that NLR was positively correlated with age, glycosylated hemoglobin (HbA1c), triglycerides (TG), total cholesterol (TC), low-density lipoprotein (LDL), and 2-hours postprandial glucose levels. PLR was positively correlated with age, duration of T2DM, HbA1c, TG, TC, and LDL, but negatively correlated with diastolic blood pressure and fasting C-peptide levels. Binary logistic regression analysis identified that age, total number of white blood cells, PLR, and TC were significant and independent factors of diabetic LEAD. Moreover, ROC curve analysis showed that NLR and PLR were both predictive markers of LEAD in diabetes, and that the area under the PLR curve was larger than NLR.
Conclusions: NLR and PLR are positively correlated with LEAD in diabetes. PLR was superior to NLR as a predictor of LEAD in diabetes.