Endocrine Abstracts

JOINT793

Background: The relationship between metformin and dementia remains complex and controversial. Previous epidemiological studies have presented conflicting evidence regarding potential neuroprotective effects or cognitive risks associated with metformin use. This study aimed to comprehensively examine the association between metformin use, vitamin B12 intake, and dementia risk, considering both diabetic and non-diabetic populations.

Methods: A retrospective cohort study was conducted using data from 499,804 participants in the UK Biobank, selected from an initial cohort of 502,422 after excluding incomplete data. The research employed multivariate logistic regression models stratified by type 2 diabetes status and categorized vitamin B12 intake across quartiles to assess dementia risk factors and potential interactions.

Results: Of the 499,804 participants, 6,893 were diagnosed with dementia. The analysis revealed significant findings across different population subgroups. Non-diabetic males showed a marked association between metformin use and increased dementia risk (Odds Ratio 3.83, 95% Confidence Interval 1.15–12.75). Among non-diabetic females, metformin use combined with vitamin B12 deficiency was linked to elevated dementia odds (OR 1.63, 95% CI 1.04–2.55). Notably, no statistically significant associations emerged for participants with type 2 diabetes.

Conclusion: The study demonstrates that metformin use in non-diabetic individuals, particularly with vitamin B12 deficiency, may increase dementia risk. These findings warrant further investigation into the mechanisms linking metformin, vitamin B12, and cognitive health, and emphasize the importance of monitoring vitamin B12 levels in non-diabetic metformin users.