PMC

Enrollment data for study participants.

Change from baseline for delayed memory composite Z score for placebo-assigned, regular insulin-treated, and detemir-treated groups. The regular insulin group had improved memory compared with the placebo group after two (p < 0.03) and four (p < 0.05) months of treatment. No differences were observed between placebo and detemir groups.

Change from baseline volume (cm³) for key AD-related ROIs. Increased or preserved volumes were noted in four ROIs for the regular insulin-treated group compared with the placebo group: (A) left superior parietal cortex; (B) right middle cingulum; (C) left cuneus; (D) right parahippocampal gyrus (all ps < 0.05). Decreased volume was observed for the detemir group relative to placebo for (E) right cuneus and (F) right hippocampus (ps < 0.01 and 0.05), whereas preserved volume was observed for (G) left anterior cingulum and (H) left middle cingulum (ps < 0.05).

Representative relationships between changes in MRI volume and cognitive outcomes. For regular insulin-treated participants, improved memory composite Z scores were associated with increased volume for (A) right middle cingulum (r = 0.62, p < 0.05), (B) left cuneus (r = 0.82, p < 0.01), (C) left inferior parietal (r = 0.61, p < 0.04) and (D) right superior frontal (r = 0.67, p < 0.03). For the placebo group, participants who had less volume loss in (C) left inferior parietal or (D) right superior frontal cortex showed less memory decline (rs = 0.65 and 0.64, ps < 0.05). No relationships between ROI volumes and memory were observed for the detemir-treated group.