Background: Studies have suggested that adrenal incidentalomas may increase risk of cardiometabolic disease in patients. Guidelines for repeat imaging and hormonal assessment of adrenal incidentalomas are inconsistent because of inadequate studies.
Study design: Systematic review and meta-analysis.
Setting: MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, and Scopus were searched.
Synopsis: Of 1,139 studies screened; 32 met inclusion criteria: adult patients with adrenal adenoma who had 12 or more months of follow-up and outcomes of interest. Larger adrenal adenomas were less likely to have significant change in size on repeat imaging than did smaller tumors. There was no malignant transformation observed. Development of Cushing syndrome was seen in 6 of 2,745 patients. Cardiometabolic comorbid conditions were common in both MACE and NFAT patients with hypertension being the most frequently reported (64% and 58.2% respectively). Worsening of dyslipidemia was observed in both groups. Weight gain and the development of type 2 diabetes occurred more frequently in MACE than in NFAT patients (21.0% vs. 8.7%). In 1,356 patients, all-cause mortality was 11.2% (95% confidence interval, 9.5%-13.0%) for both groups over a mean follow-up of 56.3 months. Cardiovascular events accounted for 43.2% deaths. Limitations included the small number of patients in the studies assessed and the inconsistent definition of outcomes.
Bottom line: Patients with adrenal adenomas should be counseled on modifying cardiovascular risk factors whereas tumor growth, change in hormone production, and malignant transformation are less concerning based on the studies included.
Citation: Elhassan YS et al. Natural history of adrenal incidentalomas with and without mild autonomous cortisol excess: A systematic review and meta-analysis. Ann Intern Med. 2019 Jun 25;121:107-16.
Dr. Thompson is a hospitalist and assistant professor of medicine in the division of general internal medicine at Saint Louis University School of Medicine.