SUN-294 The Effects of Traumatic Brain Injury on Pituitary Function: A Systematic Review and Meta-Analysis

Background: The impact of traumatic brain injury (TBI) on pituitary function remains unclear. Yet, applying appropriate diagnostic and treatment strategies for affected patients is crucial for mitigating morbidity related to hypopituitarism and improving patient outcomes. Currently, data regarding the prevalence of post-TBI hypopituitarism and its predisposing factors are inconsistent. The goals of this systematic review and meta-analysis were to evaluate the prevalence of acute and chronic post-TBI hypopituitarism and assess for predictors of pituitary dysfunction. Methods: Ovid MEDLINE In-Process & Other Non-Indexed Citations, Ovid MEDLINE, Ovid EMBASE, Ovid Cochrane Central Register of Controlled Trials, Ovid Cochrane Database of Systematic Reviews, Scopus, Web of Science, and references of key articles were searched from inception to 2019. Studies enrolling ≥20 adult patients with TBI and reporting on pituitary dysfunction were included. A total of 992 studies were generated by the initial search. Titles and abstracts were screened in duplicate by two independent reviewers for inclusion criteria. Of these, 265 full text manuscripts were subsequently reviewed for eligibility. Predefined data were extracted from 14 representative studies for the preliminary analysis (7 cross-sectional studies, 6 prospective studies, and 1 retrospective study). Results: There was a total of 813 (78% male) patients with TBI. Of those with available data, 124/248 (50.0%) had mild TBI, 112/476 (23.5%) had moderate TBI, and 308/569 (54.1%) had severe TBI. Mean age at TBI diagnosis was 34.2±4.6 years, with time to evaluation of pituitary function following TBI ranging from 0 days to 120 months (mean, 27.1±35.1 months). Acute and chronic hypopituitarism was reported in 10.7% and 19.6% of patients, respectively. TBI was associated with increased risk for hypopituitarism compared to the general population (RR=765.8, 95% CI 538.8-1088.5). Secondary hypogonadism was noted in 15.7% of patients, growth hormone deficiency in 15.7%, secondary adrenal insufficiency in 11.6%, secondary hypothyroidism in 8.7%, and diabetes insipidus in 0.2%. Older age (40.4±5.5 vs 36.7±1.0 years, P<0.0001) and higher BMI (25.0±0.7 vs 23.9±0.2 kg/m(2), P<0.0001) were associated with increased risk of post-TBI hypopituitarism. Conclusion: Available moderate- to low-quality evidence suggests that post-TBI hypopituitarism is common and correlates with older age and higher BMI. Secondary hypogonadism and growth hormone deficiency are the most predominant pituitary deficiencies. Further investigations are warranted to determine the most effective strategies for identifying patients at risk for post-TBI hypopituitarism in order to implement prompt assessment and management.