(096) Comparing Dementia and Cognitive Impairment Risks in Older Type-2 Diabetic Patients: A Danish Register-Based Study on Dipeptidyl Peptidase-4 Inhibitors vs. Glucagon-like Peptide-1 Analogues

Background: The prevalence of dementia and cognitive impairment (CI) in type-2 diabetes older patients is 15-25% and 30-60%, respectively, thus affecting quality of life and health outcomes. There is therefore the need of head-to-head studies aiming at identifying the optimal treatment for individuals with type-2 diabetes at increased risk of CI and dementia.

Objectives: This study focuses on the risk of developing CI and dementia in Danish patients treated with Dipeptidyl Peptidase-4 Inhibitors (DPP-4i) and Glucagon-like Peptide-1 Analogues (GLP-1a) using administrative and healthcare registers.

Methods: An active comparator design with a 3 years follow-up period was used. The main outcome was the hospital admission with a diagnosis of CI or dementia. Multivariate Cox Regression analysis was performed using the High Dimensional Propensity Score to obtain adjusted Hazard Ratio (HR) estimates. Inverse Probability of Treatment Weighting (IPTW) and marginal structured model were used to calculate risk differences while accounting for the variations of confounders throughout the follow-up period.

Results: Our results show a significant higher risk of dementia between DPP-4i and GLP-1a in unadjusted [HR (95% CI) =3.14 (2.4-4.1), p = 0.001] and adjusted analyses [HR (95% CI) =1.5 (1.16-2.04), p = 0.003]. No statistically significant differences were observed for CI. IPTW resulted stable throughout the follow-up period. Marginal structure modelling (β (95% CI) = 0.020 (0.018-0.021), p < 0.001) resulted in a higher risk of dementia for DPP-4i when compared to GLP-1a.

Conclusions: In conclusion, DPP-4i were associated with an increased risk of developing dementia when compared to GLP-1a among older individuals with type-2 diabetes.