ESPE Abstracts

Introduction: Peripheral diabetic neuropathy (PDN), clinical or subclinical, of large-diameter nerve fibers or small-diameter nerve fibers is a common complication of type 1 diabetes mellitus (T1DM).

Aims: Early detection of the prevalence of subclinical PDN by assessing the function of small and large nerve fibers in children and adolescents with T1DM.

Methods: The study included 53 children and adolescents with T1DM aged (mean (± SE) 15.8±0.54 years, with a disease duration of 6.0 ± 0.51 years and a HbA1c: 7.9±0.19%, along with 37 healthy controls of similar age (15.6±0.52 years) and gender. The vibration perception threshold (VPT) was estimated on the upper and lower limbs using a biothesiometer, assessing the function of large nerve fibers and the quantitative sensory testing (QST), on the palm, sole and cheek, for the study of small somatic nerve fiber function. In controls 95% confidence intervals for VPT and QST were calculated.

Results: Among patients, abnormal VPT was found on the index finger in 29 (64.5%) patients, on the thumb in 33 (73.4%), on the big toe in 33 (73.4%) and on the ankle in 27 (60%) patients. Higher VPT values in the upper and lower extremities were found in the patients compared to controls on all examined sites (P <0.01). Regarding QST, among patients, cold detection threshold (CDT) prevalence of abnormality ranged between 7.3% and 39.0% on different sites, while the prevalence of CPT (cold pain threshold) abnormalities ranged from 22.22% to 29.63% in different sites. In terms of hot stimuli, HDT (hot detection threshold) abnormality among patients ranged between 34.14% and 63.41% on different sites, while the prevalence of abnormal HPT (hot pain threshold) ranged from 15.79% to 36.84%. VPT in controls was associated with height (r =0.48, P = 0.05). In patients, cold perception was associated with BMI (re=0.42, P = 0.05) and diabetes duration, (r =0.40, P = 0.05). Hot pain thresholds in patients were associated with age (r =0.36, P = 0.05) and height (r =0.35, P = 0.05), while in controls with BMI (re=0.51, P = 0.05). No correlation of VPT or QST variables with glycemic control (HbA1c) was observed.

Conclusion: The children and adolescents with T1DM in this study, although asymptomatic, presented a high prevalence of impaired indices of peripheral neuropathy of large and small nerve fibers, early in the course of the disease. The above findings have significant clinical implications for early identification and prevention of PDN.