Echo Intensity Band Analysis for Assessing Skeletal Muscle Quality in Older Women with Type 2 Diabetes and Peripheral Arterial Disease

Background: Type 2 Diabetes Mellitus (T2DM) and Peripheral Arterial Disease (PAD) are associated with impaired skeletal muscle quality; however, the impact of T2DM alone and the additional burden of concomitant PAD on echo intensity (EI) band distribution remain unclear. This study evaluated these associations in older women using EI band analysis. Methods: Twenty-four older women were allocated into three age-matched groups: GT2DM + PAD (n = 8), GT2DM (n = 8), and healthy participants (HPG; n = 8). Ultrasound images of the vastus lateralis (VL), Tibialis Anterior (TA), Rectus Femoris (RF), and Medial Gastrocnemius (MG) were obtained. Muscle quality was assessed by pixel distribution across EI bands (0 to 255 A.U.) Results: In the VL, the GT2DM + PAD showed a significantly lower percentage of pixels in the 0–50 band compared with GT2DM (p = 0.020) and HPG (p = 0.039), and higher percentages in the 51–100 band (p = 0.018 and p = 0.030, respectively). For the MG, both GT2DM and GT2DM + PAD exhibited fewer pixels in the 0–50 band and higher values in the 51–100, 101–150, and 151–200 bands than HPG (p < 0.05). Conclusions: T2DM, alone or combined with PAD, was associated with altered skeletal muscle quality, characterized by a shift toward higher EI bands, suggesting increased non-contractile tissue content.