The Severity of Growth Hormone Deficiency Does Not Predict the Presence or Absence of Brain Magnetic Resonance Imaging Abnormalities - A Retrospective Review

Background: The Growth Hormone Research Society recommends that all patients diagnosed with growth hormone deficiency (GHD) should undergo brain magnetic resonance imaging (MRI). This is still a point of controversy in patients with mild GHD, as the level of peak growth-hormone (GH) as a predictor of brain MRI abnormality has not yet been established. The objective of this study was to determine if peak GH level, determined by stimulation tests, can predict the presence or absence of brain MRI abnormality.

Methods: This study was a retrospective chart review from 2008-2015. Patients were aged 2-18 years, and had growth failure and GHD as determined by stimulation test. Patients with history of brain tumour, chemotherapy and brain surgery, prior to the diagnosis of GHD, were excluded.

Results: A total of 386 patients were included. GH values (mild versus severe GHD) did not predict brain MRI abnormality with any agent (clonidine: p=0.07; arginine: p=0.17; glucagon: p=0.42). Abnormal MRI was apparent in 19.2% of the patients with mild GHD and 24.8% of the patients with severe GHD (p=0.17). Severe MRI abnormality was seen in 6.1% of the patients with mild GHD and 15.0% of the patients with severe GHD (p=0.009).

Conclusions: The severity of GHD based on peak GH levels on stimulation tests did not predict the presence or absence of brain MRI abnormalities in our study population; however, severe GHD was more strongly associated with severe brain MRI abnormalities. Based on these results we recommend obtaining brain MRI in all patients with GHD.