Neuropsychological Profiles of Children With Type 1 Diabetes 6 Years After Disease Onset

Abstract

OBJECTIVE—To describe neuropsychological profiles and their relationship to metabolic control in children with type 1 diabetes 6 years after the onset of disease. RESEARCH DESIGN AND METHODS—Children with type 1 diabetes (n = 90), aged 6–17 years, who had previously been assessed soon after diagnosis and 2 years later, were reevaluated 6 years after the onset of disease. Their neuropsychological profiles were compared with those of individuals in a community control group (n = 84), who had been assessed at similar intervals. Relationships between illness variables, such as age at the onset of disease and metabolic control history, and neuropsychological status were also examined. RESULTS—Six years after onset of disease, children with type 1 diabetes performed more poorly than control subjects on measures of intelligence, attention, processing speed, long-term memory, and executive skills. Attention, processing speed, and executive skills were particularly affected in children with onset of disease before 4 years of age, whereas severe hypoglycemia was associated with lower verbal and full-scale intelligence quotient scores. CONCLUSIONS—Neuropsychological profiles of children with type 1 diabetes 6 years after the onset of disease are consistent with subtle compromise of anterior and medial temporal brain regions. Severe hypoglycemia, particularly in very young children, is the most plausible explanation for neuropsychological deficits, but the contributory role of chronic hyperglycemia warrants further exploration.

Intelligence and Diabetes Mellitus Type 1

“…This results seems to contradict, in part, the findings by Northam et al (2001), who, when comparing the performance of children with DM1 to the performance of children with typical development without the disease, found lower scores in children with DM1 for their global performance (FSIQ) on the WISC-III, especially in children who were diagnosed before the age of four and had severe episodes of hypoglycemia. Brands, Biessels, Haan, Kappelle e Kessels (2005), when comparing diabetic and nondiabetic children, found that the former presented lower scores regarding intellectual abilities.…”

Postnatal age influences hypoglycemia-induced neuronal injury in the rat brain

“…Of functional significance, the affected brain regions in P14 and P28 brains subserve attention and short-and long-term memory functions [9,10]. Thus, our results may provide histochemical correlates for the impaired attention and memory functions that are common in newborn infants and children with history of hypoglycemia [24,31].…”

Effects of insulin on long-term potentiation in hippocampal slices from diabetic rats

“…There is also evidence for an increased incidence of dementia in diabetic patients [21,22,23]. The mechanisms underlying these cognitive deficits remain uncertain with concerns being raised about the effects of insulin/ hypoglycaemic therapies and the underlying illness itself [4,24].…”

“…These problems are typically thought to result from hypoglycaemic attacks [1,2], which occur more frequently during intensive insulin therapy [3]. Although insulininduced hypoglycaemia could contribute to learning problems [4], one recent prospective study did not find a relationship between severe hypoglycaemic events and cognitive impairment [5], raising the possibility that the diabetic condition alone might adversely affect learning and memory. Experimental evidence supporting an independent effect of diabetes upon brain function comes from studies showing that diabetic rats show memory impairment in the absence of insulin treatment or hypoglycaemia [6].…”