2型糖尿病と前サルコペニア

2型糖尿病の有無による前サルコペニアの有病割合の違いをインド人で調査した報告を紹介します。

Viknesh Prabu Anbalagan, Vijayachandrika Venkataraman, Rajendra Pradeepa, Mohan Deepa, Ranjit Mohan Anjana, and Viswanathan Mohan. The Prevalence of Presarcopenia in Asian Indian Individuals With and Without Type 2 Diabetes. Diabetes Technology & Therapeutics. ahead of print. doi:10.1089/dia.2013.0068.

対象は2型糖尿病患者76人と、年齢・性別をマッチングさせた糖尿病ではない方76人です。平均年齢が44歳（28-67歳）、平均BMIが25.7と高齢者を対象にはしていません。

前サルコペニアの有病割合は、DEXAの筋肉量で判定しています。2型糖尿病患者では39.5%、対照群では15.8%に前サルコペニアを認め、糖尿病群で有意に前サルコペニアが多かったです。平均の骨格筋指数も糖尿病群で有意に低い結果でした。

骨格筋指数は、BMI、腹囲と正の相関を認め、年齢、血糖値、HbA1c、LDLコレステロールと負の相関を認めました。多変量解析では、糖尿病の有無は独立して前サルコペニアと関連を認めました。

以上より、2型糖尿病患者では高齢者でなくても前サルコペニアの有病割合が高いという結論です。糖尿病によって筋障害や神経障害から骨格筋萎縮が生じる影響と、サルコペニアによってインスリン抵抗性が悪化する影響の両者があるのだと思います。

Abstract
Objective: This study compared the skeletal muscle mass and prevalence of presarcopenia between Asian Indian individuals with and without type 2 diabetes.

Subjects and Methods: Participants with type 2 diabetes (n=76) and age- and sex-matched controls without diabetes (n=76) were drawn from the Chennai Urban Rural Epidemiological Study (CURES), which was carried out on a representative sample of Chennai City in South India. Skeletal muscle mass was estimated by dual-energy X-ray absorptiometry, and skeletal muscle mass index (SMI) was calculated by dividing the appendicular skeletal muscle mass by the square of the individual's height in meters and expressed as kg/m². Presarcopenia was defined as an SMI of ≤7.26 kg/m² for males and ≤5.5 kg/m² for females. Biochemical and anthropometric measurements were done using standardized procedures.

Results: The 152 participants included 68 women (44.7%). Mean age was 44±9 years (range, 28–67 years), and the mean body mass index (BMI) was 25.7±3.8 kg/m². The prevalence rates of presarcopenia among individuals with and without diabetes were 39.5% and 15.8%, respectively (P=0.001). The mean SMI values were significantly lower in those with diabetes (6.84±1.02 kg/m²) compared with participants without diabetes (7.28±1.01 kg/m²) (P=0.009). SMI showed a positive correlation with BMI and waist circumference but a negative correlation with age, fasting plasma glucose, glycated hemoglobin, and low-density lipoprotien cholesterol in the total study population. Logistic regression analysis showed that diabetes was independently associated with presarcopenia (P=0.001).

Conclusions: Prevalence of presarcopenia is higher among Asian Indian subjects with type 2 diabetes compared with age- and sex-matched participants without diabetes.