Surgical remission for Cushing's disease associated with autoimmune disease
More than 10% of patients with surgical remission of Cushing's disease had developed a new autoimmune disease by three years after surgery, compared to only 1.6% of patients with nonfunctioning pituitary adenomas.
Patients with surgical remission of Cushing's disease have higher incidence of autoimmune disease than age- and sex-matched patients with nonfunctioning pituitary adenomas (NFPAs), a study found.
Researchers conducted a retrospective matched cohort analysis to determine the incidence of autoimmune disease in patients with Cushing's disease after surgical remission compared with patients with NFPAs, as well as the clinical presentation of and risk factors for autoimmune disease after Cushing's disease remission. They assessed cumulative incidence of new-onset autoimmune disease at three years after surgery, using late-night salivary cortisol levels, 24-hour urine free cortisol ratio, and dexamethasone suppression tests. Results of the study, which was funded by Recordati Rare Diseases Inc., were published Feb. 20 by Annals of Internal Medicine.
At three years, incidence of new-onset autoimmune disease was higher in patients with Cushing's disease than in those with NFPAs (10.4% [95% CI, 5.7% to 15.1%] vs. 1.6% [95% CI, 0% to 4.6%]; hazard ratio, 7.80 [95% CI, 2.88 to 21.10]). Patients with Cushing's disease showed higher prevalence of postoperative adrenal insufficiency (93.8% vs. 16.5%) and lower postoperative nadir serum cortisol levels (63.8 nmol/L vs. 282.3 nmol/L) than patients with NFPAs. Compared with patients with Cushing's disease without autoimmune disease, those who developed autoimmune disease had a lower preoperative 24-hour urine free cortisol ratio (6.3 vs. 2.7) and a higher prevalence of family history of autoimmune disease (20.9% vs. 41.2%).
The study authors noted that the small sample of patients who developed autoimmune disease limited their ability to build a multivariable model to identify independent risk factors. "Patients with [Cushing's disease] who have a family history of autoimmune disease should be carefully monitored after achieving remission," they wrote. "In addition, higher doses of early postoperative glucocorticoid replacement might be associated with decreased risk for development of autoimmune disease."