The Effect of Recurrent Severe Hypoglycemia on Cognitive Performance in Children With Type 1 Diabetes

Abstract

The purpose of this study was to investigate the existence and extent of cognitive impairment in type 1 diabetic children with episodes of recurrent severe hypoglycemia, using meta-analysis to synthesize data across studies. The meta-analysis sample included: 441 children with diabetes and recurrent severe hypoglycemia, 560 children with diabetes and without recurrent severe hypoglycemia. Overall, children with type 1 diabetes and recurrent severe hypoglycemia had slightly lower performance than diabetic children without severe hypoglycemia, only in some cognitive domains: intelligence, memory, learning, and verbal fluency/language. Greater impairment was found in memory and learning. No impairment was found for motor speed. Our results seem to confirm the hypothesis that recurrent severe hypoglycemia has a selective negative effect on the children's cognitive functions. However, these results must be considered with caution taking into account factors such as small sample sizes, the different definitions of severe hypoglycemia, and the variety of neuropsychological tests used.

Risk Factors for Decline in IQ in Youth With Type 1 Diabetes Over the 12 Years From Diagnosis/Illness Onset

“…Early age of diabetes onset was associated with a decline in PIQ and FSIQ scores, while a history of hypoglycemic seizures was associated with a decline in VIQ. These findings are consistent with previous reports documenting adverse effects on cognition in those with diabetes onset very early in life (14,17,20) and in those who experience serious hypoglycemia (5,17,20,22,23). Thus the associations reported are not novel, but our access to IQ scores from diagnosis and followup provides particularly compelling evidence that the timing of diabetes onset and exposure to serious hypoglycemia are significant factors in the cognitive sequelae of type 1 diabetes.…”

“…In our sample, a history of hypoglycemic seizure/coma compromised VIQ, consistent with other data documenting an association between poorer language skills and positive seizure history (20,21,23,32). These findings suggest that clinical management regimens designed to avoid such events are warranted well into adolescence, despite the apparent resilience to hypoglycemic events shown by adults (33).…”

“…There is a growing literature documenting pathophysiological CNS changes (4)(5)(6)(7)(8)(9)(10)(11)(12)(13) and neurocognitive deficits (14)(15)(16)(17)(18)(19)(20)(21)(22)(23) in youth with type 1 diabetes. However, attempts to identify specific diabetes-related risk factors for CNS compromise have produced inconclusive findings.…”

“…However, neuroimaging findings are inconsistent, with some studies finding no association between hypoglycemia history and structural brain changes (4,12) while others report positive correlations, but with little consistency between the brain regions affected (5,7,(9)(10)(11). Metaanalytic cognitive studies also provide contrasting findings, with one reporting positive association between hypoglycemia history and cognitive deficit (23) and another finding no association (14).…”

11. Children and Adolescents

“…Although it was previously thought that young children were at risk for cognitive impairment after episodes of severe hypoglycemia, current data have not confirmed this notion (18)(19)(20). Furthermore, new therapeutic modalities, such as rapidand long-acting insulin analogs, technological advances (e.g., continuous glucose monitors, low glucose suspend insulin pumps), and education may mitigate the incidence of severe hypoglycemia (21).…”