Adrenalectomy Improves Muscle Strength in Patients with Mild Autonomous Cortisol Secretion: A Comparative Study

Background/Objectives: Mild autonomous cortisol secretion (MACS) is increasingly recognized in patients with adrenal incidentalomas. While associated with cardiometabolic risk, management strategies remain controversial, particularly regarding functional outcomes. This retrospective comparative cohort study evaluated the impact of adrenalectomy versus conservative management on muscle strength in MACS patients. Materials and Methods: Forty patients with MACS (1-mg dexamethasone suppression test > 1.8 µg/dL) were enrolled: 15 underwent adrenalectomy and 25 received conservative management. Hand grip strength was measured using calibrated dynamometry, and gait speed was assessed with the 1-m walk test at baseline and 6 months. Results: Baseline characteristics are summarized descriptively for the surgical and conservative cohorts. At 6 months, the surgery group showed significant improvements in right hand grip strength (+1.19 ± 0.64 kg, p < 0.001) and left hand grip strength (+1.15 ± 0.49 kg, p < 0.001), representing approximately 5% improvement. In contrast, the conservative group exhibited significant decreases in strength over the same period (right: −0.40 ± 0.25 kg; left: −0.28 ± 0.28 kg, both p < 0.001). The post-surgical 1-mg dexamethasone suppression test decreased from 4.05 ± 1.44 to 1.01 ± 0.34 µg/dL (p < 0.001). Conclusions: Adrenalectomy results in significant improvement in objective muscle strength in MACS patients, with improvement observed in parallel to biochemical resolution of cortisol excess. In contrast, conservative management was associated with progressive decline in grip strength over 6 months. Hand grip dynamometry provides valuable functional outcome data that may guide surgical decision-making in MACS management.