Investigating the changes in volumes of the limbic system and hypothalamic-subnuclei in patients with depression

Background: Depression is consistently linked to changes in the hypothalamus, HPA axis, and limbic system, though the specific substructures involved remain unclear. This study aims to explore the relationship between depression and the volumes of specific nuclei within these brain regions. Understanding these connections could provide deeper insights into the biological mechanisms underlying depression. Methods: Seventy-three healthy individuals and 39 patients with depression were assessed using the Beck Depression Inventory or Hamilton Depression Rating Scale. All participants underwent 3.0T MRI, and the volumes of subnuclei in the hypothalamus and limbic system were measured. Results: The results revealed increased volumes in both the inferior tubular areas of the hypothalamus and the left hypothalamus in the patient group with depression. Moreover, the left infTub volume initially increased during the first three years of depression, followed by a decrease, suggesting distinct structural changes between early and chronic stages of the illness. Conclusions: Alterations in the left inferior tubular area volume suggest a connection between the hypothalamus and the chronicity of depressive symptoms. Further exploration of specific nuclei in the hypothalamus promises deeper insights into depression's biological mechanisms.