Original Abstract

AIMS: Patients with type 2 diabetes mellitus (T2DM) have a significantly increased risk of cognitive impairment, and the protective effects of traditional hypoglycaemic drugs on cognitive function remain unclear. This study systematically evaluated the neuroprotective effects of GLP-1 receptor agonists (GLP-1RAs) based on randomized controlled trial (RCT) evidence, aiming to provide key evidence-based insights for optimizing diabetes management strategies. MATERIALS AND METHODS: A comprehensive literature search was conducted across PubMed, Embase, Cochrane Library, Web of Science, CNKI, Wanfang, and ClinicalTrials.gov databases to identify studies investigating the impact of GLP-1RAs on cognitive function in T2DM patients, with the search timeframe extending up to July 2025. The analysis focused on RCTs comparing the effects of GLP-1RAs versus placebo (or conventional therapy) on neurocognitive function in T2DM patients. RESULTS: Based on the inclusion criteria, 18 RCTs involving 11 114 participants were included in the primary meta-analysis. Pooled results demonstrated that, compared to the placebo group, GLP-1RA treatment significantly increased Mini-Mental State Examination (MMSE) scores by a weighted mean difference (WMD) of 1.33 (95% CI: 0.67-1.99; I2 = 82%) and Montreal Cognitive Assessment (MoCA) scores by a WMD of 1.70 (95% CI: 0.83-2.56; I2 = 96%). The effect size on MMSE was significantly greater with long-term GLP-1RA use (≥24 weeks) compared to short-term use (<24 weeks) (mean difference = 3.74; t = 6.52, df = 269, p < 0.0001; Cohen's d = 0.79). Sensitivity analyses yielded results closely aligned with the primary analysis, indicating robust stability. Jadad scale assessment confirmed that all included studies achieved a score ≥3. CONCLUSIONS: Current evidence indicates that GLP-1 RA-based therapy may improve cognitive function in patients with type 2 diabetes mellitus compared with placebo. Furthermore, long-term administration or early initiation of GLP-1 RA treatment may offer greater cognitive benefits.