Do children and adolescents with type 1 diabetes mellitus (T1DM) show differences in cognitive performance compared with peers without T1DM? A systematic review and meta-analysis published in BMJ Open Diabetes Research & Care evaluated cognitive outcomes across multiple domains in individuals aged 19 years or younger.

The review included 129 studies identified from five databases. Cognitive assessments were grouped into five domains: academic performance, executive function, intelligence, language, and memory and learning. Comparisons with non-T1DM peers were synthesized using an evidence map. A random-effects meta-analysis of 16 studies involving 1594 participants assessed differences in Wechsler Full Scale Intelligence Quotient (IQ) scores.

Across domains, findings were mixed. In studies that included comparisons, worse outcomes in T1DM were reported in some but not all analyses. Executive function and memory outcomes showed variability across studies. Intelligence outcomes also varied, with some studies reporting lower scores in T1DM. In large studies with at least 1000 participants, no differences were observed for academic performance or language outcomes.

In the meta-analysis, children with T1DM had slightly lower IQ scores compared with peers without T1DM (mean difference −3.49; 95% confidence interval −6.16 to −0.82; p = 0.010). These findings show small differences in cognitive outcomes in some domains, with overall variability across studies.