The prevalence of growth hormone deficiency in survivors of subarachnoid haemorrhage: results from a large single centre study

Abstract

Objective: The variation in reported prevalence of growth hormone deficiency (GHD) post subarachnoid haemorrhage (SAH) is mainly due to methodological heterogeneity. We report on the prevalence of GHD in a large cohort of patients following SAH, when dynamic and confirmatory pituitary hormone testing methods are systematically employed.

Design: In this cross-sectional study, pituitary function was assessed in 100 patients following SAH. Baseline pituitary hormonal profile measurement and glucagon stimulation testing (GST) was carried out in all patients. Isolated GHD was confirmed with an Arginine stimulation test and ACTH deficiency was confirmed with a short synacthen test.

Results: The prevalence of hypopituitarism in our cohort was 19% and the prevalence of GHD was 14%. There was no association between GHD and the clinical or radiological severity of SAH at presentation, treatment modality, age, or occurrence of vasospasm. There were statistically significant differences in terms of Glasgow Outcome Scale (GOS; p = 0.03) between patients diagnosed with GHD and those without. Significant inverse correlations between GH peak on GST with body mass index (BMI) and waist hip ratio (WHR) was also noted (p < 0.0001 and p < 0.0001 respectively).

Conclusion: Using the current testing protocol, the prevalence of GHD detected in our cohort was 14%. It is unclear if the BMI and WHR difference observed is truly due to GHD or confounded by the endocrine tests used in this protocol. There is possibly an association between the development of GHD and worse GOS score. Routine endocrine screening of all SAH survivors with dynamic tests is time consuming and may subject many patients to unnecessary side-effects. Furthermore the degree of clinical benefit derived from growth hormone replacement in this patient group, remains unclear. Increased understanding of the most appropriate testing methodology in this patient group and more importantly which SAH survivors would derive most benefit from GHD screening is required.

Keywords: Growth hormone deficiency; Hypopituitarism; Subarachnoid haemorrhage.

Fig. 1

Flowchart demonstrating progression of patients through the study protocol. Only male hypogonadism was detected in this cohort. *Five patients diagnosed with ACTH deficiency on GST, were deemed to be sufficient after results were re-reviewed (see results section)

Fig. 2

Correlation between peak GH on GST with BMI and WHR. a Peak GH response on GST versus BMI in all patients in our cohort, R = −0.519 (p < 0.001), b Peak GH response on GST versus waist to hip ratio (WHR), R = −0.434 (p < 0.001)