Endocrine Abstracts

Subarachnoid haemorrhage (SAH) is a well reported cause of hypopituitarism but the precise incidence is controversial. We aimed to prospectively determine the incidence of acute and long term hypopituitarism in SAH.

We prospectively recruited 100 patients (61% female, median age 53 (range 16–82)) with non-traumatic aneurysmal SAH. Each patient had plasma sodium, urea, osmolality, glucose, and 0900 h cortisol (PC) measured on days 1, 2, 3, 4, 6, 8, 10 and 12 following SAH. Results were compared with 15 patients admitted to ITU following vascular surgery. A PC <300 nmol/l in a patient in ITU was regarded clinically as inappropriately low. Survivors attended for insulin tolerance testing at ≥6 months following SAH. Those in whom insulin tolerance testing was contraindicated underwent glucagon stimulation testing. If patients refused either of these tests, a short synacthen test was offered.

14% of SAH patients had at least one PC <300 nmol/l; in 4/14 (28.6%) hyponatraemia due to acute cortisol deficiency ensued, which responded to hydrocortisone treatment. In contrast, all controls had PC >500 nmol/l on day 1, and >300 nmol on days 2–12. 11% of SAH patients developed acute cranial diabetes insipidus (CDI); mortality in this group was 100%.

39/89 (43.8%) of SAH survivors attended for dynamic pituitary testing. The median time to testing was 15 months (range 7–30 months). 24/39 (61.5%) underwent insulin tolerance testing. 4/39 (10.3%) underwent glucagon stimulation testing and 11/39 (28.2%) underwent short synacthen testing. 2/39 (5.1%) were ACTH deficient, one of whom previously had low PC. 7/39 (17.9%) were GH deficient; one GH deficient patients previously had low PC. No patients were gonadotropin, TSH, or prolactin deficient. None had long term CDI.

In the largest prospective study of its kind, acute glucocorticoid deficiency occurs in 14% of SAH patients, and causes hyponatraemia in 28.6% of these. Long term hypopituitarism is uncommon following SAH and predominantly manifests as GH deficiency.

Declaration of interest: The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project.

Funding: This research did not receive any specific grant from any funding agency in the public, commercial or not-for-profit sector.