Postprandial and Orthostatic Hypotension Treated by Sitagliptin in a Patient with Dementia with Lewy Bodies

BACKGROUND Postprandial hypotension, induced by an absorption of glucose from intestine, could be treated by acarbose; however, it was unclear whether dipeptidyl peptidase-4 inhibitor reduced postprandial hypotension. CASE REPORT A 78-year-old woman who had experienced episodes of dizziness and hypotension after eating was admitted to our hospital. During 24-hour ambulatory blood pressure monitoring, there were repeated episodes of marked postprandial hypotension; i.e., a significant systolic blood pressure reduction within two hours after eating (from -58 to -64 mm Hg after meals). The patient was diagnosed with dementia with Lewy bodies. The patient exhibited postprandial hyperglycemia and hypotension after a 75 g oral glucose tolerance test. After the administration of 25 mg sitagliptin, the patient's postprandial and orthostatic hypotension was reduced remarkably. Moreover, her Mini-Mental State Examination score subsequently increased (from 22 to 25 points). CONCLUSIONS The dipeptidyl peptidase-4 inhibitor sitagliptin can delay postprandial increases in glucose levels and hypotensive episodes, as well as sympathetic nervous system abnormalities and orthostatic hypotension.