We observed significantly higher levels of GDF15 in the Addison’s disease cohort who were glucocorticoid deficient than in the matched healthy volunteer cohort 739.1 ± 225.8 pg/mL versus 497.9 ± 167.7 pg/mL (P = .01), respectively (Fig. 1B). This evidence concerns the gene GDF15 and primary adrenal insufficiency.