Clinical research on the change of neutrophil-lymphocyte ratio in newly diagnosed type 2 diabetic patients

Abstract

Objective To investigate the change of neutrophil/lymphocyte ratio (NLR) in the peripheral blood of newly diagnosed type 2 diabetic patients and the correlation between NLR and glycometabolism. Methods Clinical data of 521 subjects undergoing medical examinations or receiving diagnoses and treatments in the Third Affiliated Hospital of Sun Yat-sen University-Lingnan Hospital between January 2010 and December 2012 were retrospectively studied. The informed consents of all patients were obtained and the local ethical committee approval had been received. According to different blood glucose levels, the subjects were divided into the type 2 diabetes group, prediabetes group and euglycemia group. The type 2 diabetes group was composed of newly diagnosed type 2 diabetes subjects without any treatments before, including 258 subjects. Among them, 127 were males and 131 were females with an average age of (54±12) years old. Among the 80 subjects of the prediabetes group, 30 were males and 50 were females with an average age of (55±12) years old. Among the 183 subjects of the euglycemia group, 76 were males and 107 were females with an average age of (55±9) years old. Leucocyte count, percentage of neutrophil and lymphocyte, absolute value of neutrophil and lymphocyte, and NLR were compared among the three groups. In addition, according to the FPG levels, the subjects were divided into the FPG≤7 mmol/L group, 7 mmol/L<FPG<11 mmol/L group and FPG≥11 mmol/L group. While according to the HbA1c levels, the subjects were divided into the HbA1c≤6.5% group, 6.5%<HbA1c<9% group and HbA1c≥9% group. The correlations between NLR and FPG, HbA1c were analyzed. The comparisons of clinical indexes of the type 2 diabetes group, prediabetes group and euglycemia group subjects were conducted using one-way ANOVA analysis, with LSD-t test for pairwise comparison. The correlation analysis between NLR and blood glucose level was conducted using Pearson correlation analysis. Results There were no statistical difference among the type 2 diabetes group, prediabetes group and euglycemia group in leucocyte count and neutrophil absolute value (F=0.228, 2.735, P>0.05). Compared with those in euglycemia group, percentage and absolute value of neutrophil in the type 2 diabetes group were significantly higher, percentage of lymphocyte was significantly lower, and the NLR was significantly higher (LSD-t=6.332, 3.111, 4.299, 5.016, P<0.05). Compared with those in euglycemia group, percentage of neutrophil in the prediabetes group was significantly higher, percentage of lymphocyte was significantly lower, and the NLR was significantly higher (LSD-t=2.154, 2.785, 2.871, P<0.05). NLR increased gradually along with the increase of FPG and HbA1c, NLR was positively correlated with FPG and HbA1c (r=0.14、0.12, P<0.05). Conclusions Increased NLR level was found in newly diagnosed type 2 diabetic patients, indicating some degree of chronic inflammation. Increased NLR level was related to poor blood glucose control and it may become a new index to predict the chronic inflammation status of type 2 diabetes. Key words: Diabetes mellitus, type 2; Neutrophil/lymphocyte ratio; Chronic inflammation