INS and Alzheimer disease: When compared with the baseline values, a significant increase in sMMSE scores (p=0.034) in the sitagliptin group has been reported; on the other hand, in the subgroup analysis of patients without AD, it has been demonstrated that the patients receiving only sitagliptin or insulin achieved higher sMMSE scores when compared to the patients receiving metformin (p=0.024) [22].