尿毒症性サルコペニア

尿毒症性サルコペニアのレビュー論文を紹介します。

Ibrahim H. Fahal. Uraemic sarcopenia: aetiology and implications. Nephrol. Dial. Transplant. (2013) doi: 10.1093/ndt/gft070

尿毒症患者では筋肉量減少を認めやすくなります。この原因はサルコペニアと同様、多くの要因が絡んでいます。尿毒症性サルコペニアを認めると死亡率が高くなるため、筋肉量減少の予防と治療が重要です。尿毒症性サルコペニアという言葉を用いることで腎臓領域で重要性が認識されると思われます。

腎臓領域での筋肉量減少はProtein-Energy Wasting（PEW）という言葉で説明されることが多いと思っていました。尿毒症性サルコペニアという言葉は初めて聞きました。PEWも原因の1つとされています。確かにこの言葉のほうが関心が高まる可能性はあると思います。

尿毒症性サルコペニアはもちろん、加齢以外の原因も含まれる二次性サルコペニアということになります。慢性腎不全では加齢によるサルコペニアより悪液質や低栄養の要素のほうが強いのではと思いますが、広義のサルコペニアの概念を広めるにはよい言葉かもしれません。

Abstract
The term uraemic myopathy has been used loosely to describe the skeletal muscle abnormalities in uraemic patients. However, it does not fully explain the observed abnormalities as recent research has documented a normal skeletal muscle physiology in the presence of reduced muscle force, selective structural changes and significant muscle wasting. Ageing is associated with sarcopenia (muscle wasting) and an increase in the prevalence of chronic kidney disease (CKD), which accelerates the normal physiological muscle wasting. Similar to sarcopenia, muscle wasting in uraemic patients appears to be the hallmark of the disease and its aetiology is multifactorial with hormonal, immunologic and myocellular changes, metabolic acidosis, reduced protein intake and physical inactivity. Uraemic sarcopenia presents a high probability for morbidity and mortality and consequently a high priority for muscle wasting prevention and treatment in these patients. Perhaps, the use of the term ‘uraemic sarcopenia’ would provide recognition by the renal community for this devastating problem. The purpose of this review is to relate the findings of the recent publications that describe abnormalities in uraemic skeletal muscle to the possible pathogenesis of muscle wasting and its consequences in patients with CKD.