Association between quantitative ultrasound biomarkers associated to muscle mass and quality and extracted from raw data and blood-based biomarkers and combinations thereof with clinical variables including frailty, sarcopenia, physical function, disability, nutritional status, body composition, and Quality of Life in three cohorts of older adults: hospital control cohort, hospital exercise cohort, and primary care cohort.
Muscle quality and mass: Ultrasound. Thickness (mm), cross-sectional area (cm²), perimeter (mm) and pennation angle (°). Frailty: FRAIL scale range 0-5. Frailty phenotype (0-5). Sarcopenia: SARC-F scale (0-10). Disability: GDS, 7 stages. Barthel index (0-100). Lawton and Brody index 0-8. Physical function: SPPB (0-12). IPAQ (0-3). Gait speed test, seconds. Grip strength, Jamar dynamometer, kilograms.
Quality of life: EQ 5D-5L, scale of 0-100.
Blood biomarkers: Vitamin D, Lutein zeaxanthin, Troponin T, Pro-BNP, and sRAGE with ELISA, miRNAs (qRT-PCR).