サルコペニアと嚥下障害の論文

今日は、Denise Ney,at al: Swallowing: Impact, Strategies and Interventions. Nutr Clin Pract. 2009 ; 24(3): 395–413. doi:10.1177/0884533609332005.の論文を紹介します。知人のSTから入手しました。全文入手も可能です。

高齢者の嚥下障害に関するレビューの論文ですが、サルコペニアと嚥下障害に関する記載も下記のようにあります。

Sarcopenia
Structurally, sarcopenia is associated with age-related reductions in muscle mass and crosssectional area, a reduction in the number or size of muscle fibers, and a transformation or selective loss of specific muscle fiber types (18). Sarcopenia is inherently associated with diminished strength. There are reports in the literature of sarcopenia-like changes in muscles of the upper aerodigestive tract (19–21) and the observed age-related changes in strength and function (5,6) suggest pervasive changes in lingual muscle composition (22–24). Ongoing work is generating novel interventions effective for diminishing sarcopenia and increasing strength. Although most of the initial work in this area has been performed in the limb musculature, emerging work in cranial-innervated muscles is quite relevant to swallowing in older individuals and will be discussed later in more detail.

一部訳しますとサルコペニア様の変化が上気道消化管に認められる。舌の筋肉組成にも加齢による変化を認める。頭蓋の神経支配を受ける筋肉のサルコペニアは高齢者では嚥下と関連している。

サルコペニアの研究は主に四肢の筋肉に関して行われてきましたが、最近は舌も含めて嚥下に関わる筋肉に関して行われつつあります。

個人的意見でしかありませんが、私は嚥下障害の原因疾患の第2位が広義のサルコペニア（加齢に伴う嚥下筋力低下だけでなく、廃用による嚥下障害、疾患による嚥下障害：侵襲、悪液質、筋疾患、低栄養による嚥下障害も含めて）と考えています。1位はもちろん脳卒中です。

明らかな麻痺を認めない嚥下障害のかなりの部分を、サルコペニアによる嚥下障害で説明できて、リハ栄養的な治療計画を立てられるのではないかと感じています。もちろん心因性、頸椎由来、器質的な嚥下障害も少なからずありますので、麻痺がない場合にすべてをサルコペニアによる嚥下障害と言うわけにはいきませんが…。

また、ここには引用していませんが、嚥下障害とサルコペニアは高齢者の院内感染の予測因子であるという論文もあります。サルコペニアによる嚥下障害の研究はまだあまり行われていませんが、高齢社会の日本では、その重要性は今後確実に増していくと考えています。

Abstract
The risk for disordered oropharyngeal swallowing (dysphagia) increases with age. Loss of swallowing function can have devastating health implications including dehydration, malnutrition, and pneumonia, as well as reduced quality of life. Age-related changes place older adults at risk for dysphagia for two major reasons: One is that natural, healthy aging takes its toll on head and neck anatomy and physiologic and neural mechanisms underpinning swallowing function. This progression of change contributes to alterations in the swallowing in healthy older adults and is termed presbyphagia, naturally diminishing functional reserve. Second, disease prevalence increases with age and dysphagia is a co-morbidity of many age-related diseases and/or their treatments. Sensory changes, medication, sarcopenia and age-related diseases are discussed herein. Relatively recent findings that health complications are associated with dysphagia are presented. Nutrient requirements, fluid intake and nutritional assessment for older adults are reviewed relative to their relations to dysphagia. Dysphagia screening and the pros and cons of tube feeding as a solution are discussed. Optimal intervention strategies for elders with dysphagia ranging from compensatory interventions to more rigorous exercise approaches are presented. Compelling evidence of improved functional swallowing and eating outcomes resulting from active rehabilitation focusing on increasing strength of head and neck musculature is provided.
In summary, while oropharyngeal dysphagia may be life-threatening, so are some of the traditional alternatives, particularly for frail, elderly patients. While the state of the evidence calls for more research, this review indicates the behavioral, dietary and environmental modifications emerging in this past decade are compassionate, promising and in many cases preferred alternatives to the always present option of tube feeding.