Philadelphia, PA, 19 July, 2011 - Imaging studies have repeatedly found that people with depression have smaller hippocampal volumes than healthy individuals. The hippocampus is a brain region involved in learning and memory, spatial navigation, and the evaluation of complex life situations or "contexts". However, because in prior studies hippocampal volume was only measured in people once they became depressed, it has been unclear whether a small hippocampus renders a person vulnerable to developing depression, or whether it is a consequence of depression.
A new study published in Biological Psychiatry has approached that problem by following a large population of elderly individuals over a 10 year period.
Researchers performed an initial imaging scan on subjects to obtain a baseline measurement of their hippocampal volume and then performed follow-up scans 5 and 10 years later. During this time, they also repeatedly assessed the individuals for both depressive symptoms and depressive disorders.
Corresponding author Dr. Tom den Heijer explains their findings: "We found that persons with a smaller hippocampus were not at higher risk to develop depression. In contrast, those with depression declined in volume over time. Our study therefore suggests that a small hippocampal volume in depressed patients is more likely an effect of the depression rather than a cause."
"The principal importance of this type of research is that it may provide insight into age-related impairments in the function of the hippocampus," reflected Dr. John Krystal, Editor of Biological Psychiatry. "For example, in Alzheimer's disease, memory problems and disorientation are prominent symptoms, reflecting among other things the impaired function of the hippocampus."
Future studies will be needed to better understand whether current treatments protect the hippocampus and hippocampal function.
Notes to Editors
The article is "A Study of the Bidirectional Association Between Hippocampal Volume on Magnetic Resonance Imaging and Depression in the Elderly" by Tom den Heijer, Henning Tiemeier, Hendrika J. Luijendijk, Fedde van der Lijn, Peter J. Koudstaal, Albert Hofman, and Monique M.B. Breteler. The authors are affiliated with Erasmus Medical Center, Rotterdam, the Netherlands. den Heijer is also from Sint Franciscus Gasthuis, Rotterdam, the Netherlands. Luijendijk is also from Bavo, Europoort, the Netherlands. The article appears in Biological Psychiatry, Volume 70, Number 2 (July 15, 2011), published by Elsevier.
The authors' disclosures of financial and conflicts of interests are available in the article.
John H. Krystal, M.D. is Chairman of the Department of Psychiatry at the Yale University School of Medicine and a research psychiatrist at the VA Connecticut Healthcare System. His disclosures of financial and conflicts of interests are available at http://journals.elsevierhealth.com/webfiles/images/journals/BPS/Biological_Psychiatry_Editorial_Disclosures_03_29_11.pdf.
Full text of the article mentioned above is available to reporters upon request. Contact Chris J. Pfister at c.pfister@elsevier.com to obtain a copy or to schedule an interview.
About Biological Psychiatry
This international rapid-publication journal is the official journal of the Society of Biological Psychiatry. It covers a broad range of topics in psychiatric neuroscience and therapeutics. Both basic and clinical contributions are encouraged from all disciplines and research areas relevant to the pathophysiology and treatment of major neuropsychiatric disorders. Full-length reports of novel results, commentaries, case studies of unusual significance, and correspondence judged to be of high impact to the field are published, particularly those addressing genetic and environmental risk factors, neural circuitry and neurochemistry, and important new therapeutic approaches. Concise reviews and editorials that focus on topics of current research and interest are also published rapidly.
Biological Psychiatry (www.sobp.org/journal) is ranked 4th out of 126 Psychiatry titles and 15th out of 237 Neurosciences titles in the 2010 ISI Journal Citations Reports® published by Thomson Reuters. The 2010 Impact Factor score for Biological Psychiatry is 8.674.
About Elsevier
Elsevier is a world-leading provider of scientific, technical and medical information products and services. The company works in partnership with the global science and health communities to publish more than 2,000 journals, including The Lancet and Cell, and close to 20,000 book titles, including major reference works from Mosby and Saunders. Elsevier's online solutions include SciVerse ScienceDirect, SciVerse Scopus, Reaxys, MD Consult and Nursing Consult, which enhance the productivity of science and health professionals, and the SciVal suite and MEDai's Pinpoint Review, which help research and health care institutions deliver better outcomes more cost-effectively.
A global business headquartered in Amsterdam, Elsevier employs 7,000 people worldwide. The company is part of Reed Elsevier Group PLC, a world-leading publisher and information provider, which is jointly owned by Reed Elsevier PLC and Reed Elsevier NV. The ticker symbols are REN (Euronext Amsterdam), REL (London Stock Exchange), RUK and ENL (New York Stock Exchange).
Journal
Biological Psychiatry