Can EWGSOP2 and SDOC Definitions of Sarcopenia Identify Functional Muscle Quality?

Area of Science:

• Gerontology
• Muscle Physiology
• Biomedical Diagnostics

Background:

• Sarcopenia, a progressive loss of skeletal muscle mass and function, affects aging populations.
• Standardized diagnostic criteria are crucial for consistent sarcopenia identification and management.
• Existing criteria like EWGSOP2 and SDOC require comparative analysis for their effectiveness in assessing muscle quality.

Purpose of the Study:

• To compare the European Working Group on Sarcopenia in Older People (EWGSOP2) and the Sarcopenia Definition and Outcomes Consortium (SDOC) criteria.
• To evaluate their efficacy in identifying muscle quality indexes (MQI) and lower limb muscle performance in women aged 65 and older.

Main Methods:

• 96 women aged ≥ 65 were classified into sarcopenia groups (GS) or non-sarcopenia groups (GNS) based on EWGSOP2 and SDOC criteria.
• Lower limb peak torque (PT), maximal work (MW), and power (POW) were measured using an isokinetic dynamometer.
• Muscle quality index (MQI) was calculated, adjusted for body mass index (BMI) and lower limb lean tissue mass (LTM).

Main Results:

• Both EWGSOP2 and SDOC identified sarcopenia groups with significantly lower muscle performance and BMI-adjusted MQI.
• SDOC criteria showed significant associations with all measured lower limb muscle performance and MQI variables.
• Adjusted models indicated that sarcopenia (SDOC) was linked to reduced muscle quality (MQI_POW/LTM OR = 0.67; MQI_PT/LTM OR = 0.76).

Conclusions:

• Sarcopenia diagnosis by EWGSOP2 and SDOC criteria is associated with impaired muscle function and quality in older women.
• The SDOC definition demonstrated a superior ability to differentiate muscle contraction quality components between individuals with and without sarcopenia.