Objective: To describe body composition, lipid profile, and health-related quality of life (HRQL) in patients with traumatic brain injury (TBI) in relation to the development of posttraumatic hypopituitarism.

Design: Cross-sectional with a nested prospective sub-study.

Patients: The cross-sectional cohort included 104 hospitalized patients with TBI (26F/78M; age: median 41yrs. (range 18–64); BMI: 25kg/m² (17–39); severity: mild (Glasgow Coma Scale score (GCS) 13–15) n = 44, moderate (GCS 9–12) n = 20, severe (GCS < 9) n = 40). A nested cohort of 46 patients was followed prospectively.

Measurements: Body mass index (BMI), waist circumference, lipid profile, total- and regional- fat mass was assessed 3 and 12 months (prospective) or only 12 months (cross-sectional) post-traumatically. HRQL questionnaires (NHP, EQ-5D and the GH deficiency specific instrument – QoL-AGHDA) were completed ‘pre-traumatically’, 3 and 12 months (prospective) or only 12 months (cross-sectional) post-traumatically.

Results: Patients with posttraumatic hypopituitarism had higher age-, gender- and BMI- adjusted 12 months LDL-cholesterol, waist circumference, and total fat mass (P < 0.05 in all cases), and a higher increase in total cholesterol (P = 0.01) during follow-up compared with sufficient patients. These findings were unrelated to 12 months IGF-I and IGF-I SD-scores.

Hypopituitary patients also had worse age-, BMI- and TBI severity- adjusted overall EQ-5D VAS (P = 0.03) and QoL-AGHDA (P = 0.01) scores, and worse NHP dimension scores of sleep (P = 0.03), energy (P = 0.02), and social isolation (P = 0.04), compared to patients with an intact pituitary function.

Conclusion: Posttraumatic hypopituitarism was an independent predictor of the classical phenotypic features of hypopituitarism including an unfavorable lipid and body-composition profile, as well as worsened HRQL.