Miguel A. Vázquez Ronda, Hospital Universitario Infanta Sofia, Spain,
J Nutr Health Aging. 2021;25(8):956-963. doi: 10.1007/s12603-021-1669-4.
Different methods have been proposed to study skeletal muscle mass in sarcopenia diagnosis, although all have inherent drawbacks. The aim of this study was to evaluate the utility of muscle ultrasound in muscle assessment by studying its correlation with dual-energy x-ray absorptiometry (DXA) and calf circumference (CC), cut-off values for ultrasound-based detection of low muscle mass, and the correlation with muscle performance.
Fifty-seven participants older than 70 years, underwent a muscle ultrasound study, DXA, calf circumference (CC) and functional assessment. Ultrasound measurements were taken in the femoral quadriceps (transverse plane) and in the medial gastrocnemius (transverse and longitudinal planes). Muscle function was assessed by gait speed, Short Physical Performance Battery (SPPB) and grip strength.
Median age was 78.9 years (IQR 74.9 - 81.9), and 33 were women (57.9%). We found good correlation between muscle thickness of gastrocnemius muscle in transverse and longitudinal plane and appendicular lean mass measured by DXA (r=0.546 and r=0.689 respectively) and good correlations between muscle thickness of gastrocnemius in transverse and longitudinal plane with CC (r=0.651 and r=0.447 respectively). The thickness of gastrocnemius medialis optimal cut-off points for low muscle mass were 18,5mm in the transverse plane (Sensitivity: 77,8%, Specificity: 77,1%), and 17.3mm in the longitudinal plane (Sensitivity: 100%,Specificity: 68.8%). Muscle thickness was also significantly correlated with gait speed, SPPB and grip strength.
Measures of gastrocnemius medialis thickness obtained by ultrasound are reliable and correlate well with DXA and CC values and muscle performance.
尽管已经提出了多种方法来研究肌少症诊断中的骨骼肌质量，但所有方法都存在固有缺陷。本研究旨在通过研究肌肉超声与双能 X 射线吸收法（DXA）和小腿围（CC）的相关性、基于超声检测低肌肉量的截断值以及与肌肉功能的相关性，来评估肌肉超声在肌肉评估中的应用价值。
57 名年龄大于 70 岁的参与者接受了肌肉超声检查、DXA、小腿围（CC）和功能评估。在股四头肌（横切面）和内侧比目鱼肌（横切面和纵切面）进行超声测量。肌肉功能通过步态速度、简易体能状况量表（SPPB）和握力来评估。
中位年龄为 78.9 岁（IQR 74.9-81.9），33 名女性（57.9%）。我们发现，比目鱼肌的横切面和纵切面肌肉厚度与 DXA 测量的四肢瘦体重有很好的相关性（r=0.546 和 r=0.689），比目鱼肌的横切面和纵切面肌肉厚度与 CC 也有很好的相关性（r=0.651 和 r=0.447）。比目鱼肌内侧厚度的低肌肉量最佳截断点为横切面 18.5mm（灵敏度：77.8%，特异性：77.1%），纵切面 17.3mm（灵敏度：100%，特异性：68.8%）。肌肉厚度与步态速度、SPPB 和握力也有显著相关性。
超声测量的比目鱼肌厚度是可靠的，与 DXA 和 CC 值以及肌肉功能有很好的相关性。
