サルコペニアと悪液質と心不全

高齢者のサルコペニアと悪液質とうっ血性心不全のレビュー論文を紹介します。

Zamboni M, Rossi A, Corzato F, Bambace C, Mazzali G, Fantin F. Sarcopenia, Cachexia and Congestive Heart Failure in the Elderly. Endocr Metab Immune Disord Drug Targets. 2013 Jan 15. [Epub ahead of print]

軽中度の慢性心不全患者に骨格筋異常や骨格筋減少はよく認め、疲労や呼吸困難に影響している可能性があります。骨格筋異常としてサルコペニア（原発性）と心臓悪液質が考えられます。悪液質では筋肉量減少が特徴的ですが、サルコペニアの方の多くは悪液質ではありません。

体重減少、食欲不振、全身炎症反応がない場合には、サルコペニアが疑われます。容易ではありませんが、慢性心不全患者でサルコペニアと悪液質を区別することは治療上、重要です。悪液質の特異的な治療方法はありませんが、サルコペニアなら治療の選択肢があります。

原発性サルコペニアと悪液質を区別することは、リハ栄養的には広義のサルコペニアの原因検索と対応につながりますので、重要だと同感します。ただ、悪液質に対しては決定的な治療方法がないとはいえ、栄養・運動・薬物などの包括的対応はすべきだと考えます。

Abstract

Skeletal muscle abnormalities and loss are frequently present in patients with mild or moderate cardiac heart failure (CHF) and may contribute to fatigue and dyspnea. These muscle abnormalities may be associated with age related body composition changes, such as sarcopenia. Muscle damage has also been observed in subjects with cardiac cahexia, a serious CHF complication, associated with poor prognosis independently of functional disease severity, age, and measures of exercise capacity and cardiac function. Loss of muscle mass is a feature of cachexia, whereas most sarcopenic subjects are not cachectic. Individuals with no weight loss, no anorexia, and no measurable systemic inflammatory response may be sarcopenic. Patients with severe CHF show multiple marked histological abnormalities of skeletal muscle, such as muscle fiber atrophy. These abnormalities are different in sarcopenia and cachexia. The majority of mechanisms involved in sarcopenia play a role even in the determination of cachexia and they are amplified in cachexia where they may induce both muscle damage as well as other abnormalities, such as fat and weight loss, through activation of lypolisis or anorexia. To distinguish cachexia and sarcopenia in CHF patients, even if not easy, should be clinically relevant, because no specific treatment is available for cachectic patients whereas treatment options are possible for sarcopenia.