Bilirubin is inversely related to diabetic peripheral neuropathy assessed by sural nerve conduction study

• Published in: Journal of diabetes investigation 2021-11, Vol.12 (11), p.2028-2035
• Main Authors: Abe, Kentaro, Maeda, Yasutaka, Matsuzaki, Chitose, Yokomizo, Hisashi, Inoue, Tomoaki, Sonoda, Noriyuki, Ogawa, Yoshihiro, Inoguchi, Toyoshi
• Format: Article
• Language: English
• Subjects: Age; Aged; Albuminuria - diagnosis; Alcohol; Arteriosclerosis; Bilirubin; Bilirubin - blood; Biomarkers - blood; Body mass index; Cross-Sectional Studies; Diabetes; Diabetes mellitus; Diabetes Mellitus - blood; Diabetes Mellitus - physiopathology; Diabetic neuropathies; Diabetic Neuropathies - diagnosis; Diabetic Neuropathies - epidemiology; Diabetic neuropathy; Diabetic retinopathy; Diabetic Retinopathy - diagnosis; Diabetic Retinopathy - epidemiology; Diagnosis; Female; Flow velocity; Foot diseases; Glomerular Filtration Rate; Hospitals; Humans; Incidence; Laboratories; Male; Microvasculature; Middle Aged; Nephropathy; Nerve conduction; Neural Conduction; Neuromuscular diseases; Original; Oxidative stress; Peripheral Nervous System Diseases - diagnosis; Peripheral neuropathy; Predictive Value of Tests; Regression analysis; Retinopathy; Risk Factors; Sensitivity and Specificity; Statistical analysis; Sural nerve; Sural Nerve - physiopathology; Tendons; Test methods; Training; Values
• ISSN: 2040-1116; 2040-1124
• DOI: 10.1111/jdi.13568

Aims/Introduction Diagnosis of diabetic peripheral neuropathy (DPN) depends on subjective findings, certain investigations for DPN risks have not been performed enough. Bilirubin protects against vascular complications by reducing oxidative stress in diabetes, but is not fully tested for DPN. This study aimed to evaluate sural nerve conduction impairments (SNCI) as an objective DPN marker and the contribution of bilirubin to SNCI. Materials and methods Using DPN‐Check®, SNCI was defined as a decline of amplitude potential or conduction velocity below the normal limit in 150 inpatients with diabetes. The correlations between SNCI and conventional DPN diagnosis criteria, the incidence of diabetic retinopathy/nephropathy, biomarkers for atherosclerosis, cardiac function by ultrasonic cardiogram, and bilirubin were statistically tested, followed by the comparison of logistic regression models for SNCI to find confounders with bilirubin. Results The incidence of SNCI was 72.0%. The sensitivity and specificity of SNCI for DPN prediagnosis by simplified criteria were 54.6 and 90.5%, respectively, and similarly corresponded with diabetic retinopathy and nephropathy (sensitivity 57.4 and 50.0%, respectively). SNCI significantly related to diabetes duration, declined estimated glomerular filtration rate, albuminuria and total bilirubin. SNCI incidence was attenuated in the higher bilirubin tertiles (89.8/65.3/54.8%, P