Deterioration of Cough Reflex Sensitivity and the Urge-to-Cough in Dementia with Lewy Bodies

2018 Fiscal Year Final Research Report

• Project/Area Number: 26460899
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: General internal medicine(including psychosomatic medicine)
• Research Institution: Kyorin University (2016-2018); Tohoku University (2014-2015)
• Principal Investigator: EBIHARA TAKAE 杏林大学, 医学部, 准教授 (30396478)
• Co-Investigator(Kenkyū-buntansha): 海老原 覚 東邦大学, 医学部, 教授 (90323013)
• Project Period (FY): 2014-04-01 – 2019-03-31
• Keywords: 咳衝動 / 咳反射 / レビー小体型認知症 / アルツハイマー型認知症 / 肺炎

Outline of Final Research Achievements

Cough is an important respiratory symptom that predominantly involves the brainstem, and the urge-to-cough(UTC) can be modulated by the cerebral cortex. Previous studies on Lewy body disease showed decreased cough reflex sensitivity and decline in the central respiratory chemosensitivity. We investigated the relationships cognition has with the cough reflex and the UTC, as well as to compare the difference in responses of patients with DLB and patients with other dementia such as Alzheimer disease (AD) or non-dementia. The cough reflex sensitivities were estimated based on the lowest concentrations of inhaled citric acid which could induce two or more coughs or five or more coughs. Subjects were asked to rate the UTC based on its threshold concentrations (Cu), using the modified Borg scale. The cough reflex sensitivity and the perceived UTC in patients with DLB were deteriorated, compared with other groups. This result might be valuable in treating patients with DLB.

Free Research Field

老年医学

Academic Significance and Societal Importance of the Research Achievements

認知症の代表疾患の一つであるアルツハイマ―型認知症や健常高齢者と比較して、レビー小体型認知症における咳衝動と咳反射が低下していることは、本人が認知症であることも相まって、肺炎発症の診断のタイミングが遅れる、あるいは、診断したときには、すでに重症である危険性を示唆する根拠となると考えられる。