Object: The aim of this prospective observational study was to assess the incidence and pattern of hypopituitarism after diffuse axonal injury (DAI) and to identify its effect on these patients in terms of functional outcome.
Methods: Of 1307 patients with traumatic brain injury treated at the authors' institution between March 2005 and June 2008, 65 patients with DAI were enrolled in the present study. The authors determined basal hormone levels, initial Glasgow Coma Scale scores, the Marshall CT grades, the presence of abnormal signal intensity indicating lesions on MR images, and duration of unconsciousness. At the 6-month follow-up visits, functional outcomes were estimated using the Modified Barthel Index. Univariate and multivariate analyses were performed to identify factors that influenced functional outcomes.
Results: Twenty-one patients with hypopituitarism (Group A) had more lesions in the body of the corpus callosum, basal ganglia, thalamus, and the gray-white matter junction than those without hypopituitarism (Group B). In Group A, growth hormone deficiency (17 patients, 80.9%) was the most common, and multiple pituitary hormone deficiencies were found in 12 patients (57.1%). The mean Modified Barthel Index score at the 6-month follow-up was 64.7 in Group A and 88.5 in Group B (p = 0.027). Duration of unconsciousness (p = 0.035), the Marshall CT grade (p = 0.021), hypopituitarism (p = 0.044), and abnormal signal intensities on MR imaging in midline or deep structures of the brain (p = 0.001) were found to be associated with functional outcome.
Conclusions: The findings in this prospective observational study suggest that hypopituitarism in patients with DAI has a relationship not only with injuries in the midline or deep structures of the brain, but also with a poor outcome.