Low blood sugar in children affects memory

Episodes of low blood sugar (hypoglycaemia), particularly at an early age can affect spatial memory in children with type 1 diabetes. Researchers from the Washington University School of Medicine, St. Louis, USA conducted a study that tests and supports a common hypothesis that severe hypoglycaemia experienced early in life is riskier for cognitive function than severe hypoglycaemia experienced later in life. They focused only on a spatial memory task, which has previously been shown to be sensitive to repeated hypoglyacemia. The researchers studied data from three independent studies involving 103 diabetic children and 60 children without diabetes between 6 and 18 years old. The 2-hour battery of cognitive measures included evaluation of short (5-second) and long (60-second) spatial memory and reactions. This involved recalling locations and responding to shapes shown on a computer screen. Children who had more than three episodes of severe hypoglycaemia showed reduced performance on the longer spatial response test. This was particularly the case when severe hypoglycaemic episodes began before the age of 5 years. The age at which type 1 diabetes developed and estimates of chronic high blood sugar levels did not influence performance. The developing brain of very young children may be more vulnerable than the brain of older children to the negative effect of severe hypoglycaemia on longer-term spatial memory. However, more research needs to be done on how this effect relates to everyday life.