Effect of glycemic control on cognitive function in patients with type 1 diabetes mellitus: a systematic review and meta-analysis

Abstract

Background It is controversial whether the level of glycemic control in patients with type 1 diabetes mellitus (T1DM) correlates with reduced cognitive function. This study explored the influence of glycemic management quality on cognitive function in T1DM patients by examining the association between glycemic control level and impaired cognitive function. Methods The electronic databases PubMed, Embase, Cochrane Library, China National Knowledge Infrastructure, China Science and Technology Journal database, Wanfang database, and China Biology Medicine disc database were systematically searched to identify eligible studies published before January 2023. Search, selection, and data extraction were performed by two independent reviewers. RevMan 5.4 software was used for meta-analysis, and standardized mean difference (SMD) between groups was calculated. Results Six studies involving 351 patients with T1DM were included in this study. Compared with T1DM subjects with good glycemic control, those with poor glycemic control performed worse in full-scale intellectual quotient (P = 0.01, SMD = −0.79, 95%CI = −1.42 to −0.17), but no significant differences were observed in verbal intellectual quotient (P = 0.08, SMD = −1.03, 95%CI = −2.20 to 0.13), memory (P = 0.05, SMD = −0.41, 95%CI = −0.82 to 0.00), and attention (P = 0.23, SMD = −0.26, 95%CI = −0.69 to 0.16). Conclusions T1DM patients with suboptimal glycemic control may have a worse cognitive function, mainly focusing on the full-scale intellectual quotient. The current study highlights the significance of maintaining satisfactory glycemic control in T1DM patients to improve their health status and quality of life. Standardized tests should be employed in clinical neuropsychological practice to provide early and complete cognitive assessment of individuals with poor glycemic control. Systematic review registration The study protocol has been registered in the PROSPERO database (CRD42023390456).