Association between plasma mid‐regional pro‐adrenomedullin levels and muscle properties

Aim Adrenomedullin exerts a vasodilative effect and is thought to be associated with skeletal muscle properties by regulating microcirculation. This cross‐sectional study aimed to clarify the possible association in older adults aged ≥65 years. Methods The study population included 978 community residents (mean age 71.5 years) who participated in the medical checkup. Mid‐thigh skeletal muscle mass and fat infiltration into the muscle was assessed using computed tomography images. Plasma levels of mid‐regional pro‐adrenomedullin, a stable fragment derived from pro‐adrenomedullin in a 1:1 ratio with adrenomedullin, were measured using blood drawn at the medical checkup, and quartiles were calculated for analysis. Results Mid‐regional pro‐adrenomedullin did not show significant association with the mid‐thigh skeletal muscle cross‐sectional area, an index of muscle mass (Q1: 217 ± 50, Q2: 218 ± 48, Q3: 215 ± 48, Q4: 212 ± 45 cm 2 , P = 0.544). Muscle subtype analysis showed that mid‐regional pro‐adrenomedullin was inversely associated with fewer fat (high intensity) muscle areas and positively associated with fat‐rich (low intensity) muscle areas, resulting in an inverse association with mean muscle intensity, an index of muscle quality (Q1: 50.3 ± 4.2, Q2: 49.6 ± 4.5, Q3: 49.1 ± 4.3, Q4: 47.1 ± 4.6 HU, P < 0.001). This association remained significant after adjustment of possible covariates, including anthropometric factors and glycemic factors (Q1: reference, Q2: β = −0.078, P = 0.018, Q3: β = −0.099, P = 0.004, Q4: β = −0.180, P < 0.001). Conclusion Adrenomedullin is associated with muscle quality, but not with muscle mass. Geriatr Gerontol Int 2025; ••: ••–•• .