CT-based body composition enhances prognostic performance of PASO score for surgical outcome in primary aldosteronism

Primary aldosteronism (PA), the most common cause of secondary hypertension, is associated with greater cardiovascular risk than essential hypertension. The Primary Aldosteronism Surgical Outcome (PASO) score incorporates body mass index (BMI) as one of its predictors and has demonstrated usefulness in predicting surgical outcomes. Computed tomography (CT)-derived body composition measures, particularly visceral fat area (VFA), have the potential to enhance the prediction of surgical outcomes in PA beyond the PASO score. We analyzed patients with PA who underwent unilateral adrenalectomy at Severance Hospital between January 2005 and December 2017. Body composition measures, including L3 VFA, skeletal muscle area, and L1 trabecular bone Hounsfield unit (HU), were manually annotated from preoperative CT. Surgical outcomes at 12 months were defined according to PASO criteria. Among a total of 165 patients (mean age 47.5 years, 60% women), complete, partial, and absent clinical success were observed in 67 (41%), 85 (51%), and 13 (8%) patients, respectively. Patients achieving complete success had a higher proportion of women, lower BMI, lower VFA, and higher bone HU. In multivariable models adjusted for clinical covariates including PASO score, both VFA and bone HU were independently associated with complete success (adjusted odds ratio [95% CI] per one SD increment: VFA, 0.62 [0.40-0.96]; bone HU, 1.84 [1.10-3.06]). Incorporating VFA and bone HU into the PASO-based model significantly improved discrimination for complete clinical success (AUC 0.76 vs. 0.66; p = 0.003). CT-derived VFA and bone HU enhanced the prognostic performance of the PASO score for clinical success after adrenalectomy in patients with PA.