Executive Function in Adults With Type 2 Diabetes: A Meta-Analytic Review

Objective To examine the extent to which Type 2 diabetes mellitus (T2DM) is associated with impairments in executive function (EF). Methods Medline, PsychoInfo, and Scopus databases and published references were used to identify articles examining the association between T2DM status (case versus control) and EF decrements. Results from studies were converted to standardized mean differences and compared using random-effects models. Moderator analysis was conducted for age, sex, and diabetes duration using maximum likelihood estimation. Results Sixty studies (59 articles) including 9815 individuals with T2DM and 69,254 controls were included. Findings indicated a small but reliable association between T2DM status and EF decrements (d = -0.248, p < .001), observed across all aspects of EF examined: verbal fluency, mental flexibility, inhibition, working memory, and attention. Disease duration significantly moderated the effect of T2DM status on EF. Conclusions T2DM is associated with a mild-to-moderate EF decrements. Such decrements are stronger among those with shorter disease duration.