PATIENTS AGE IS A SIMPLE PREDICTIVE FACTOR FOR THE DEVELOPMENT OF NELSONS SYNDROME AFTER TOTAL ADRENALECTOMY FOR CUSHINGS-DISEASE

Reportedly between 8-38% of patients who receive bilateral adrenalecto my for treatment of Cushing's disease will develop Nelson's syndrome. We investigated which factors may predict the development of the syndr ome. Eight of 48 patients, bilaterally adrenalectomized for pituitary- dependent Cushing's syndrome 1-30 yr previously, developed Nelson's sy ndrome 1.5-13 yr (6.6 +/- 4.3 yr) after adrenalectomy. The mean age at adrenalectomy in the group of patients who developed Nelson's syndrom e was significantly lower than that in the group without the syndrome (mean +/- SD, 26.0 +/- 6.0 and 35.6 +/- 11.7 yr, respectively; P < 0.0 2). In the patients adrenalectomized before the age of 35 yr, 8 of 27 (30%) developed Nelson's syndrome, whereas in the patients older than 35 yr, no one did (P < 0.02). No statistically significant differences between the two groups were found in sex ratio, duration of disease b efore adrenalectomy, or duration of follow-up thereafter. There were n o statistically significant differences between the two groups in mean plasma cortisol and ACTH levels before adrenalectomy, cortisol suppre ssibility after the administration of 8 and 16 mg dexamethasone, or co rtisol responses to CRH, TRH, and LH-releasing hormone before adrenale ctomy. We conclude that age at the time of adrenalectomy is an importa nt predictive factor for the development of Nelson's syndrome.