在宅高齢障害者の口腔、嚥下、栄養、認知とADL

日本の在宅高齢障害者の口腔、嚥下、栄養、認知とADLの関係を調査した論文を紹介します。

Furuta M, Komiya-Nonaka M, Akifusa S, Shimazaki Y, Adachi M, Kinoshita T, Kikutani T, Yamashita Y.　Interrelationship of oral health status, swallowing function, nutritional status, and cognitive ability with activities of daily living in Japanese elderly people receiving home care services due to physical disabilities.　Community Dent Oral Epidemiol. 2012 Aug 30. doi: 10.1111/cdoe.12000. [Epub ahead of print]

対象は60歳以上の在宅高齢者で何らかの在宅サービスを受けている286人です。口腔（歯の数と義歯の有無）、嚥下（頸部聴診）、ADL（Barthel Index）、認知（CDR、臨床認知症尺度）、栄養（MNA-SF）を評価して、これらの関係をパス解析で検討しています。

パス解析については、下記HPを参照してください。多変量解析の1つで、横断研究でも変数の因果関係や相互関係を図に示せるようです。上の図が今回の研究結果のパス図です。

http://psy.isc.chubu.ac.jp/~oshiolab/teaching_folder/datakaiseki_folder/10_folder/da10_01.html

結果は、歯の本数と認知機能が義歯装着に影響していて、これらによる嚥下機能低下と認知機能低下が栄養状態に影響を与えています。低栄養、嚥下障害、認知機能低下が、ADLに影響を与えています。以上より、歯の維持と義歯装着が嚥下と栄養を介して、ADLの維持・改善につながる可能性があるという結論です。

パス解析といった高度な統計手法を使うと、横断研究であってもここまで言えるのですね。ただ私に取り扱える手法ではないので、統計の専門家に相談しないと実施できそうにありません。また、歯の維持と義歯装着が嚥下と栄養を介して、ADLの維持・改善につながるかは、前向き研究での検証が必要だと思います。

Abstract

OBJECTIVES:

Malnutrition and cognitive impairment lead to declines in activities of daily living (ADL). Nutritional status and cognitive ability have been shown to correlate with oral health status and swallowing function. However, the complex relationship among the factors that affect decline in ADL is not understood. We examined direct and indirect relationships among oral health status, swallowing function, nutritional status, cognitive ability, and ADL in Japanese elderly people living at home and receiving home care services because of physical disabilities.

METHODS:

Participants were 286 subjects aged 60 years and older (mean age, 84.5 ± 7.9 years) living at home and receiving home care services. Oral health status (the number of teeth and wearing dentures) was assessed, and swallowing function was examined using cervical auscultation. Additionally, ADL, cognitive ability, and nutritional status were assessed using the Barthel Index, the Clinical Dementia Rating Scale, and the Mini Nutritional Assessment-Short Form, respectively. Path analysis was used to test pathways from these factors to ADL.

RESULTS:

The mean number of teeth present in the participants was 8.6 ± 9.9 (edentates, 40.6%). Dysphagia, malnutrition, and severe cognitive impairment were found in 31.1%, 14.0%, and 21.3% of the participants, respectively. Path analysis indicated that poor oral health status and cognitive impairment had a direct effect on denture wearing, and the consequent dysphagia, in addition to cognitive impairment, was positively associated with malnutrition. Malnutrition as well as dysphagia and cognitive impairment directly limited ADL.

CONCLUSIONS:

A lower number of teeth are positively related to swallowing dysfunction, whereas denture wearing contributes to recovery of swallowing function. Dysphagia, cognitive impairment, and malnutrition directly and indirectly decreased ADL in elderly people living at home and receiving home nursing care. The findings suggest that preventing tooth loss and encouraging denture wearing when teeth are lost may indirectly contribute to maintaining or improving ADL, mediated by recovery of swallowing function and nutritional status.