Cardiometabolic Risk Parameters in “Nonfunctioning” Adrenal Incidentalomas: A Systematic Review and Meta-analysis

Objective Several studies have investigated whether patients with nonfunctioning adrenal incidentalomas (NFAI) have an increased cardiometabolic risk, based on surrogate parameters such as the augmentation index (Aix), carotid intima-media thickness (cIMT), flow-mediated dilation (FMD), insulin resistance (IR), left ventricular mass index (LVMI), and pulse wave velocity (PWV), compared to patients without adrenal incidentalomas (AI). We sought to analyze the available literature to evaluate AIx, cIMT, FMD, IR, LVMI, and PWV in patients with NFAI as compared to patients without AI. Design Systematic review and meta-analysis. Methods We included studies that evaluated the cIMT and IR (primary outcomes) and AIx, FMD, LVMI, and PWV (secondary outcomes) in patients with NFAI vs matched subjects without AI. A random-effects model (DerSimonian and Laird) was used to calculate the standardized mean difference and 95% CI for each outcome. Results Among the 24 available studies, 21 studies provided the necessary data (2228 subjects, mean age 53.3 ± 2.9 years, 35% males). Data on cIMT, IR, AIx, FMD, LVMI, and PWV were reported in 12 (1063 subjects), 15 (1745 subjects), 2 (140 subjects), 3 (198 subjects), 3 (201 subjects), and 2 (140 subjects) studies, respectively. Compared with patients without AI, patients with NFAI showed statistically significant differences in cIMT, IR, AIx, FMD, LVMI, and PWV (standardized mean difference and 95% CI: 1.22, 0.87-1.58; 0.51, 0.32-0.69; 0.94, 0.38-1.50; -1.24, -1.84- -0.65; 0.41, 0.04-0.78; 1.03, 0.16-1.89, respectively). Conclusion Based on cIMT, IR, AIx, FMD, LVMI, and PWV levels, patients with NFAI may be at increased cardiovascular risk