Frailty in patients with mild autonomous cortisol secretion is higher than in patients with nonfunctioning adrenal tumors

Context: Mild autonomous cortisol secretion (MACS) affects up to 50% of patients with adrenal adenomas. Frailty is a syndrome characterized by the loss of physiological reserves and an increase in vulnerability, and it serves as a marker of declining health. Objective: To compare frailty in patients with MACS versus patients with nonfunctioning adrenal tumors (NFAT). Design: Retrospective study, 2003-2018 Setting: Referral center Patients: Patients >20 years of age with adrenal adenoma and MACS (1 mg overnight dexamethasone suppression (DST) of 1.9-5 µg/dL) and NFAT (DST <1.9 µg/dL). Main outcome measure: Frailty index (range 0-1), calculated using a 47-variable deficit model. Results: Patients with MACS (n = 168) demonstrated a higher age-, sex-, and body mass index–adjusted prevalence of hypertension (71% vs 60%), cardiac arrhythmias (50% vs 40%), and chronic kidney disease (25% vs 17%), but a lower prevalence of asthma (5% vs 14%) than patients with NFAT (n = 275). Patients with MACS reported more symptoms of weakness (21% vs 11%), falls (7% vs 2%), and sleep difficulty (26% vs 15%) as compared with NFAT. Age-, sex- and BMI-adjusted frailty index was higher in patients with MACS vs patients with NFAT (0.17 vs 0.15; P = 0.009). Using a frailty index cutoff of 0.25, 24% of patients with MACS were frail, versus 18% of patients with NFAT (P = 0.028). Conclusion: Patients with MACS exhibit a greater burden of comorbid conditions, adverse symptoms, and frailty than patients with NFAT. Future prospective studies are needed to further characterize frailty, examine its responsiveness to adrenalectomy, and assess its influence on health outcomes in patients with MACS.