Kyu-Man Han1, Daseul Kim1, Youngbo Sim2, June Kang3, Aram Kim3, Eunsoo Won1, Woo-Suk Tae4, Byung-Joo Ham5. 1. Department of Psychiatry, Korea University Anam Hospital, Korea University College of Medicine, Seoul, Republic of Korea. 2. Brain Convergence Research Center, Korea University Anam Hospital, Seoul, Republic of Korea. 3. Department of Biomedical Sciences, Korea University College of Medicine, Seoul, Republic of Korea. 4. Brain Convergence Research Center, Korea University Anam Hospital, Seoul, Republic of Korea; Geriatric Health Clinic and Research Institute, Korea University, College of Medicine, Seoul, Republic of Korea. Electronic address: wstae@korea.ac.kr. 5. Department of Psychiatry, Korea University Anam Hospital, Korea University College of Medicine, Seoul, Republic of Korea; Brain Convergence Research Center, Korea University Anam Hospital, Seoul, Republic of Korea. Electronic address: hambj@korea.ac.kr.
Abstract
BACKGROUND: Morphologic changes of the brainstem in major depressive disorder (MDD) have rarely been reported in neuroimaging studies, even though, monoaminergic neurotransmitters are synthesized in several brainstem regions. We aimed to investigate volume changes in each region of the brainstem and their association with antidepressant use or the remission status of MDD. METHODS: A total of 126 patients with MDD and 101 healthy controls underwent T1-weighted structural magnetic resonance imaging. We analyzed volumes of each brainstem region, including the medulla oblongata, pons, midbrain, and superior cerebellar peduncle, and the volume of the whole brainstem using the FreeSurfer. RESULTS: The patients with MDD had significantly greater midbrain volumes (P=0.013) compared to healthy controls. In particular, drug-naïve patients with MDD had significantly greater brainstem volumes compared to healthy controls (P=0.007), while no significant findings were observed between the antidepressant treatment group and healthy controls. The remitted patient group had reduced pons (P=0.002) and midbrain (P=0.005) volumes compared to healthy controls, while the non-remitted MDD patient group had significantly greater midbrain volumes compared to the healthy controls (P=0.017). LIMITATIONS: We could not distinguish gray versus white matter volumes changes in our analysis. CONCLUSIONS: We observed that the midbrain is enlarged in patients with a current depressive episode, who are not undergoing antidepressant treatment. This volume then returns to normal after antidepressant treatment, and is even reduced, when the patient is in remission. Further studies are needed to confirm our observations.
BACKGROUND: Morphologic changes of the brainstem in major depressive disorder (MDD) have rarely been reported in neuroimaging studies, even though, monoaminergic neurotransmitters are synthesized in several brainstem regions. We aimed to investigate volume changes in each region of the brainstem and their association with antidepressant use or the remission status of MDD. METHODS: A total of 126 patients with MDD and 101 healthy controls underwent T1-weighted structural magnetic resonance imaging. We analyzed volumes of each brainstem region, including the medulla oblongata, pons, midbrain, and superior cerebellar peduncle, and the volume of the whole brainstem using the FreeSurfer. RESULTS: The patients with MDD had significantly greater midbrain volumes (P=0.013) compared to healthy controls. In particular, drug-naïve patients with MDD had significantly greater brainstem volumes compared to healthy controls (P=0.007), while no significant findings were observed between the antidepressant treatment group and healthy controls. The remitted patient group had reduced pons (P=0.002) and midbrain (P=0.005) volumes compared to healthy controls, while the non-remitted MDDpatient group had significantly greater midbrain volumes compared to the healthy controls (P=0.017). LIMITATIONS: We could not distinguish gray versus white matter volumes changes in our analysis. CONCLUSIONS: We observed that the midbrain is enlarged in patients with a current depressive episode, who are not undergoing antidepressant treatment. This volume then returns to normal after antidepressant treatment, and is even reduced, when the patient is in remission. Further studies are needed to confirm our observations.