Fibrinogen function indexes are potential biomarkers of diabetic peripheral neuropathy

Background and objectives: Research suggests that diabetic peripheral neuropathy (DPN) is related to plasma fibrinogen (Fib) concentrations, although its correlation with Fib function has not been reported. Here, the kvalue and angle a, reflecting the plasma Fib function, were used to analyse its correlation with DPN, and their potential as biological indicators for diagnosing DPN was explored. Subjects and methods: This prospective observational clinical study enrolled 561 type 2 diabetes mellitus (T2DM) patients, who were divided into the diabetes with symptomatic neuropathy (161 cases), diabetes with asymptomatic neuropathy (132 cases) and diabetes with no neuropathy (268 cases) groups. Meanwhile, 160 healthy unrelated subjects were recruited as controls. Results: Fib levels increased slightly in diabetic subjects with neuropathy compared with those without. The angle alpha levels increased slightly in subjects with asymptomatic DPN compared with those with no neuropathy and increased greatly in subjects with symptomatic DPN compared with those without. The k value levels slightly decreased in subjects with asymptomatic DPN compared with those with no neuropathy and greatly decreased in subjects with symptomatic DPN compared with those without. The association of the k value and angle alpha with diabetic neuropathy was independent of the hyperglycaemic state and other potential confounders (odds ratio 0.080 [0.051-0.124], P< 0.001; odds ratio 1.131 [1.063-1.204], P< 0.001). The k value and angle alpha levels were closely correlated with neuropathy stage (r =- 0.686, P< 0.000; r = 0 .314, P < 0.001). The optimal cut-off point for k value levels to distinguish patients with diabetic neuropathy from those without was 1.8 min, with a sensitivity of 73.7% and a specificity of 83.2% (AUC=0.873). The optimal cut-off point for angle alpha levels was 60 degrees, with a sensitivity of 41.0% and a specificity of 95.6% (AUC=0.669). Conclusions: The k value and angle alpha are closely associated with DPN. The levels of the k value and angle alpha may be helpful in the early diagnosis of DPN.