A new, automated imaging technique was used to identify shrinkage of a mood-regulating brain structure in a large sample of women with multiple sclerosis who also have a certain type of depression. The study, led by Cedars-Sinai neurologist Nancy Sicotte‘s multicenter research team, found that women with MS and symptoms of “depressive affect” – such as depressed mood and loss of interest – have reduced size of the right hippocampus.
According to an article featured on the cover of the January 2014 issue of Human Brain Mapping, the left hippocampus remained unchanged, and other types of depression – such as vegetative depression, which can bring about extreme fatigue – did not correlate with hippocampal size reduction.
This new research supports earlier studies suggesting that the hippocampus may contribute to the high frequency of depression in multiple sclerosis patients. It also shows that a computerized imaging technique called automated surface mesh modeling can readily detect thickness changes in subregions of the hippocampus. This previously required a labor-intensive manual analysis of MRI images.
Depression in patients who suffer from multiple sclerosis has long been studied, particularly the specific factors that may cause depression on MS patients and possible treatments for these patients. Adding to research in this field, Sicotte and her team’s study now makes easier to identify depression in multiple sclerosis female patients.
An expert in multiple sclerosis and state-of-the-art imaging techniques, Sicotte, who is the article’s senior author, had previously found, along with other authors, evidence of tissue loss in the hippocampus, but the changes could only be documented in manual tracings of a series of special high-resolution MRI images. The new approach can use more easily obtainable MRI scans and automate the brain mapping process.
“Patients with medical disorders – and especially those with inflammatory diseases such as MS – often suffer from depression, which can cause fatigue. But not all fatigue is caused by depression. We believe that while fatigue and depression often co-occur in patients with MS, they may be brought about by different biological mechanisms. Our studies are designed to help us better understand how MS-related depression differs from other types, improve diagnostic imaging systems to make them more widely available and efficient, and create better, more individualized treatments for our patients,” Sicotte said in a press release. She received a $506,000 grant from the National Multiple Sclerosis Society last year to continue this research.
Also participating in the study were researchers from University Hospital, Hamburg, Germany; the University of Arizona, Tucson; David Geffen School of Medicine at UCLA; the University of California, San Francisco; Yale School of Medicine, New Haven, Conn.; and Feinberg School of Medicine at Northwestern University, Chicago.
The study was funded by the National Institutes of Health (NIH R01 MH59708, R01-HD043323, K01EB013633); Cousins Center for Psychoneuroimmunology and the National Institute on Aging (K01 AG028404); Marie Curie grant from the European Union (MC FP7-PEOPLE-2010-RG268381); Skirball Foundation; and Department of Defense (W81XWH-10-1-0882).