DPP4 and Alzheimer disease: A recent nationwide real-world longitudinal study (n = 701193) found that compared with metformin + sulfonylurea, metformin + dipeptidyl peptidase-4 inhibitor and metformin + thiazolidinediones were associated with a significantly lower risk of AD (HR = 0.922 and 0.812), suggesting that adding thiazolidinediones or dipeptidyl peptidase-4 inhibitor instead of sulfonylurea as second-line antidiabetic treatment contributed to delaying or preventing dementia (Kim et al., 2021).