Subclinical pain and thermal sensory dysfunction in children and adolescents with Type 1 diabetes mellitus

To assess cutaneous thermal and pain thresholds in upper and lower limbs in neurologically asymptomatic children and adolescents, and to study the relationships of clinical parameters and these sensory thresholds in subclinical diabetic neuropathy.

Thirty-five neurologically asymptomatic patients, aged 8-16 years, diagnosed with Type 1 diabetes mellitus (DM), and a control group of 35 healthy age-matched subjects participated in the study. Warmth, cold, and heat-induced pain thresholds were measured in the dorsum of the right arm and foot, using quantitative sensory testing (QST). Relevant clinical parameters, retrieved from medical records or measured at the QST session, were obtained for each patient.

Compared with controls, diabetic patients had increased thresholds for warmth in the hand (P = 0.002), and cold and warmth in the foot (P = 0.015 and P = 0.004, respectively). Of the diabetic patients, 43% showed abnormality of at least one sensory threshold. A significant correlation was observed for duration of diabetes and heat-induced pain threshold in the hand (P = 0.045), but no correlation was found for age, height, weight, pre-test blood glucose, age of onset, current insulin dose, and mean of glycosylated haemoglobin determinations of the previous 18 months. No significant correlation was found for other sensory thresholds.

Using QST, abnormal cutaneous thermal perception is a common finding, in both upper and lower limbs, in neurologically asymptomatic young diabetic patients. Heat-induced pain threshold in the hand was correlated with the duration of the diabetes.