3030 Appendicular Skeletal Muscle Mass Index: A Potential Predictor of Skeletal Muscle Abnormality According to the Severity Airflow Limitation of COPD

Friday, 16 October 2015
Hall D1 Foyer (Floor 3) (Coex Convention Center)

Jun-Hong Ahn, MD , Yeungnam University College of Medicine, Daegu, South Korea

Dong-Won Lee, MD , Andong Sungso Hospital, Andong, South Korea

Jin Hong Chung, MD , Yeungnam University College of Medicine, Daegu, South Korea

Hyun Jung Jin, MD , Department of Internal Medicine, College of Medicine, Yeungnam University, Daegu, South Korea

Min-Su Sohn, MD , Yeungnam University College of Medicine, Daegu, South Korea

Objective: To investigate the effect of COPD on the skeletal muscles, particularly in patients with limb muscle dysfunction. The appendicular skeletal muscle mass index (ASMI), an index of sarcopenia, which was recently in the limelight, is an index of the limb muscle mass and is considered useful for predicting skeletal muscle abnormality in COPD patients. Thus, their relationships were examined.

Method: This research was conducted using the data from the 4th and 5th Korea National Health and Nutrition Examination Surveys (KNHANES), which were conducted from 2008 to 2011. Of the subjects on whom dual-energy x-ray absorptiometry (DXA) was performed to confirm their body composition, 1,219 COPD patients aged over 40 years showed an FEV1/FVC < 70%. COPD is classified into three groups--mild, moderate, and severe--according to the airflow limitation. In this study, 534 subjects had mild COPD; 613, moderate; and 72, severe. For the criteria for sarcopenia, the recommended criteria of the European Working Group on Sarcopenia in Older People (EWGSOP) and of the Asia Working Group for Sarcopenia (AWGS) were used.

Results: The ASMI of each group was categorized according to the COPD severity into 7.04±1.034, 6.83±1.030, and 6.45±1.071, respectively. Thus, there were differences between all the groups, and the higher the severity, the lower the results were(p < 0.001).When the sarcopenia classification of EWGSOP according to the ASMI was applied, each group’s FEV1(L) was 2.26±0.673, 2.20±0.633, and 1.94±0.730, respectively. In the case of Class II sarcopenia, it was lower than that in the normal case and in the case of the Class I sarcopenia.(P=0.003)When the sarcopenia criteria of AWGS was applied, the FEV1(L) was 2.30±0.667 and 2.09±0.651, and the pulmonary function of the sarcopenia group was low (p < 0.001). The correlation of the FEV1(L) with the ASMI was analyzed as 0.521, higher than with the BMI or the FFMI (p < 0.001); and the regression analysis also confirmed that the ASMI had a higher R2 and standardized regression coefficient than the BMI, FFMI, and skeletal muscle mass index (SMI) (p < 0.001).It was found that when the ASMI was used, the sarcopenia risk increased in all the cases in which the criteria recommended in EWGSOP and AWGS were used; and when the criteria of the AWGS were used, the moderate and severe stages showed the odds ratios of 1.587 (95% Cl, 1.109-2.271, p = 0.012) and 3.127 (95% Cl, 1.438-6.802, p = 0.004), respectively, compared with those of the mild stage.

Conclusion: ASMI is a fast and accurate predictor of skeletal muscle abnormality caused by an increase in the severity of the airflow limitation of COPD patients.