The benefit of angiotensin converting enzyme inhibitor for geriatric syndrome in the elderly

Angiotensin converting enzyme (ACE) inhibitor plays an important role not only as an antihypertensive drug but also for prevention of various complications related to geriatric syndrome. Pneumonia in the disabled elderly is mostly due to silent aspiration of oropharyngeal bacterial pathogens to the lower respiratory tract. Aspiration is related to the dysfunction of dopaminergic neurons by cebrovascular disease, resulting in impairments in both the swallowing and cough reflexes. ACE inhibitor can increase in the sensitivity of the cough reflex particularly in older post-menopausal women, and improvement of the swallowing reflex. In a 2-year follow-up study in stroke patients, patients who did not receive ACE inhibitors had a higher risk of mortality due to pneumonia than in stroke patients who were treated with ACE inhibitor. Moreover, the mortality of pneumonia was significantly lower in older hypertensive patients given ACE inhibitors than in those treated with other antihypertensive drugs. On the other hand, we found a new benefit of ACE inhibitor on the central nervous system. The mortality in Alzheimer's disease patients who received brain-penetrating ACE inhibitor was lower than in those who received other antihypertensive drugs. In a 1-year follow-up study, cognitive decline was lower in patients receiving brain-penetrating ACE inhibitors than in patients receiving a non-brain-penetrating ACE inhibitor or a calcium channel blocker. Brain-penetrating ACE inhibitors may slow cognitive decline in patients with mild to moderate Alzheimer's disease. ACE inhibitor might be effective for the disabled elderly, resulting in the prevention of aspiration pneumonia and Alzheimer's disease for the elderly.