Glycaemic control for painful diabetic peripheral neuropathy is more than fasting plasma glucose and glycated haemoglobin

Background. - The relationship between postprandial hyperglycaemia and diabetic peripheral neuropathy (DPN), whether painful or painless, has yet to be determined. Thus, the aim of this study was to investigate the relationship in patients with type 2 diabetes (T2D). Methods. - This cross-sectional study was conducted in adults with T2D between January and October 2013. Blood samples were collected after overnight fasting every 3 months prior to enrolment. For this study, increased postprandial glycaemic exposure was defined as high glycated haemoglobin (HbA(1c)) and near-normal mean fasting plasma glucose (FPG) levels. Both painless and painful DPN were evaluated using two validated tools, the Michigan Neuropathy Screening Instrument (MNSI) and Douleur Neuropathique 4 (DN4) questionnaire. Results. - This study included 1040 participants with mean FPG levels < 140 mg/dL, 535 of which were < 126 mg/dL. Of these patients, 200/1040 (19.2%) and 105/535 (19.6%) had DPN. Multivariate analysis demonstrated that higher HbA(1c) levels (>= 7%) did not increase risk of painless DPN, but did significantly increase risk of painful DPN in T2D patients with FPG < 140 mg/dL and < 126 mg/dL, with corresponding odds ratios of 2.49 and 3.77 (95% confidence intervals: 1.09-5.71 and 1.20-11.79), respectively, after adjusting for demographic factors, diabetes-related variables and comorbidities. Conclusion. - This study is the first to reveal that increased postprandial glycaemic exposure, as assessed by high HbA1c and near-normal FPG levels, is associated with an increased risk of painful DPN in adults with T2D. (C) 2020 Published by Elsevier Masson SAS.