Source: The Science & Research of CFS, The CFIDS Chronicle Special Issue, 2005-2006. Just released, this issue is generating huge buzz in the CFS community. Copies are available through the CFIDS Association’s website at www.cfids.org for $12 each. Visit http://www.cfids.org/special/default.asp to browse a complete listing of articles, including links to several online samples.
Cognitive difficulties are found in 85-95% of CFS patients. Now, cutting-edge research from two independent international groups suggests that the volume of gray matter in the brain is significantly decreased in CFS. This decrease in brain tissue, or cerebral atrophy, may be responsible for cognitive problems in some people with CFS.
The most recent of the studies, conducted in 2005 in the Netherlands, used MRI technology to measure brain volume and tissue concentration, finding that the volume of gray matter in CFS patients was significantly decreased. What is especially interesting about this study is that after researchers found structural abnormalities in a first CFS cohort, they repeated the experiment in a second cohort of equal size and found the same results. In all, 28 patients and 28 healthy controls were tested. The researchers, led by Floris de Lange, report that when results from both cohorts were combined, the reduction in gray matter tissue in CFS patients was 8%.
This echoes the 2004 findings of a Japanese research group led by Tomohisa Okada, M.D., Ph.D., which observed “a significant reduction in gray matter volume in the bilateral prefrontal areas of CFS patients.” Investigators found an 11.8% volume reduction in the 16 CFS patients compared to the 49 healthy controls.
Both studies used a technique called voxel-based morphometry (VBM) to measure the results of the brain scan. Unlike assessment techniques that rely on human observers and rating scales, VBM is an automated procedure that provides unbiased results. While gray matter reduction was found in both studies using VBM, neither study found white matter abnormalities.
Although we don’t know if the observed cerbral atrophy is a cause of CFS or a consequence, these findings are alarming some members of the CFS patient community, who are concerned about “brain damage.” It’s important to note that the studies are small and need to be replicated by other researchers before definite conclusions can be made. And even if the results are confirmed by future investigators, the brain has a remarkable ability to adapt and rewire itself in compensatory ways [depending on the severity of the damage]. Research shows that people with CFS may use more extensive regions of the brain to process tasks and information, perhaps compensating for deficits in specific areas of the brain. There are rehabilitative techniques patients can employ to help with cognitive problems.
Reprinted with kind permission of the CFIDS Association of America, that nation’s largest non-profit organization dedicated to Chronic Fatigue Syndrome. Online at www.cfids.org.