ESPE Abstracts

Background: Diabetic neuropathy is among the least recognized complications of diabetes, despite its significant negative impact on survival and quality of life. Characteristic neuronal alterations may occur subclinically early in the course of the disease, even in childhood. The prevalence of subclinical neuropathy in paediatric population ranges from 7.9 – 19% in different studies.

Objective and hypotheses: Our objective was to study the prevalence of subclinical autonomic and peripheral neuropathy in T1DM children and adolescents and its correlations with associated factors.

Method: We evaluated 97 T1DM children and adolescents (mean±S.D. age 12.9±2.8 years, T1DM duration: 5.14±3.5 years) and 80 controls (mean±S.D. age 11.9±2.7 years). We examined pupillary dilatation (PD) in darkness, an index of autonomic neuropathy, using a Polaroid pupillometer and vibration sensation threshold (VST), an index of peripheral neuropathy, using a Biothesiometer. Abnormal cut-off values (>95% or <5%) were calculated from control values distribution. PD and VST were compared between patients and controls and were analyzed according to confounding factors.

Results: PD impairment was more frequent in the T1DM group, compared to controls (31.6% vs 3.3%, P<0.001). Moreover, in the T1DM group impaired VST were more frequent than in the controls in the lower (left: 23.3% vs 6.7%, P<0.001, right: 28.3% vs 4%, P<0.001) and upper limbs (left: 17.1% vs 2.67%, P<0.001, right: 23.2% vs 2.6%, P<0.001), respectively. PD was associated with age (r=0.16, P=0.038), HbA1c: (r=0.23, P=0.048) and diabetes duration (r=0.20, P=0.022). Moreover in the whole group, older age (P<0.001) and puberty were associated with greater proportion of abnormal VSTs in the lower limbs in pubertal vs prepubertal children (left: 17.7% vs 2.8%, P=0.001, right: 19.4% vs 0.0%, P<0.001).

Conclusion: Impaired indices of peripheral and autonomic neuropathy are present in a significant proportion of T1DM children and adolescents, although asymptomatic. Indices of diabetic neuropathy are associated with age, diabetes duration, puberty and the quality of glycaemic control.