Impact of ethnicity and antihyperglycemic medications on dementia incidence in older adults with type 2 diabetes.

Background: Type 2 diabetes increases the risk of cognitive decline and dementia. Data on ethnic differences in dementia prevalence among patients with diabetes remain limited. Methods: We conducted a retrospective matched case-control study of Clalit Health Services members aged 60 or older. Matching (1:3) was based on age, sex, language, and socioeconomic status. Ethnicity was determined by spoken language or place of birth. Prescriptions and refills for antidiabetic medications were recorded for the two years preceding the index date. Clinical, anthropometric, and comorbidity data were analyzed. Results: During follow-up, 39% of participants were diagnosed with dementia over a maximum observation period of 20 years (crude proportion). However, given a median follow-up of 9.6 years, dementia incidence was primarily evaluated using time-specific competing-risk analyses. When accounting for death as a competing event, the 10-year cumulative incidence of dementia was approximately 9-10%, varying across ethnic groups. However, in multivariable competing-risk models adjusting for age, sex, socioeconomic status, and comorbidities, ethnicity was no longer independently associated with dementia incidence. In matched analyses, the use of SGLT-2 inhibitors and DPP-4 inhibitors was associated with a lower probability of dementia. In time-to-event analyses of dementia-related mortality, treatment with SGLT-2 inhibitors, GLP-1 receptor agonists, and DPP-4 inhibitors was associated with significantly reduced mortality risk. Conclusion: Ethnic differences in dementia incidence were attenuated after adjustment for demographic and clinical factors. SGLT-2 and DPP-4 inhibitors were associated with a lower risk of dementia, whereas GLP-1 receptor agonists, DPP-4 inhibitors, and SGLT-2 inhibitors were associated with reduced dementia-related mortality.