Extent of Brain Involvement at Diagnosis May Predict Rate of Later Brain Atrophy in Patients With MS

Newswise — In patients with recently diagnosed multiple sclerosis, the extent of accumulated brain tissue loss and overall lesion load as determined by magnetic resonance imaging (MRI) may predict the rate of cerebral atrophy over the following two years, according to a report in the February issue of Archives of Neurology, one of the JAMA/Archives journals.

MRI provides valuable information about the progression of multiple sclerosis (MS), according to background information in the article. MRI is used to monitor the number and volume of MS-related lesions (damaged tissue), which can help monitor the evolution of the disease but does not appear to be associated with the patient's disability status. Brain volume, also measured by MRI, "is currently considered to be a marker of the neurodegenerative component of MS pathological features, thereby better reflecting the pathological background of irreversible clinical disability in MS," the authors write.

Bas Jasperse, M.D., and colleagues at the VU University Medical Center, Amsterdam, the Netherlands, performed brain MRI shortly after diagnosis and again after two years in 89 patients with MS (average age, 37.5). The numbers and volume of two types of lesions apparent on MRI, black hole (dark appearing lesions that indicate the loss of myelin, neurons' protective coating) and T2 (newer, brighter appearing lesions), were recorded along with brain volume. Change in brain volume between scans was calculated, and participants were also assessed for neurologic disability.

"The mean [average] annualized rate of cerebral atrophy was -0.9 percentage of brain volume change per year," the authors write. "Baseline normalized brain volume and baseline T2 lesion load were identified as explanatory variables for the subsequent percentage of brain volume change per year and yielded a regression model that explained 31.2 percent of the variance in percentage of brain volume change per year."

In other words, "patients who have acquired more brain tissue loss and more T2 lesions are prone to have a higher rate of subsequent brain atrophy," the authors conclude. "In this relationship, the extent of brain tissue loss seemed more important than lesional activity. Because a higher rate of cerebral atrophy is predictive of worse clinical functioning at a later stage in the MS disease course, our findings suggest that these two baseline variables could have prognostic value for clinical functioning in early MS." (Arch Neurol. 2007;64:190-194. Available pre-embargo to the media at http://www.jamamedia.org.)

Editor's Note: The Netherlands Organization for Scientific Research supported this study. The MS center Amsterdam is financially supported by the Dutch MS research foundation. Please see the article for additional information, including other authors, author contributions and affiliations, financial disclosures, funding and support, etc.

Editorial: Understanding How MS Worsens In patients with MS, "the unpredictable and often dramatic appearance of clinical relapses and focal MRI abnormalities tend to catch our attention," writes J. Theodore Phillips, M.D., Ph.D., of The Multiple Sclerosis Center at Texas Neurology, Dallas, in an accompanying editorial. "However, these events can often obscure more insidious, but no less important, destructive changes, such as irreversible disability progression and MRI-evident brain atrophy."

"In this issue of Archives, Jasperse and colleagues demonstrate that the rate of new brain atrophy in newly diagnosed MS patients studied over two years is significantly predicted by MRI-determined brain atrophy and T2 lesion load at the time of diagnosis. Lower brain volume and higher T2 lesion load at the time of diagnosis predict greater brain volume loss over a two-year observation period.

"This finding provides not only important clinical prognostic information, but also indicates the necessity of accounting for these baseline MRI variables in future clinical study designs that use brain atrophy as an outcome variable," Dr. Phillips continues.(Arch Neurol. 2007;64:167-168. Available pre-embargo to the media at http://www.jamamedia.org.)

Editor's Note: The Netherlands Organization for Scientific Research supported this study. The MS center Amsterdam is financially supported by the Dutch MS research foundation. Please see the article for additional information, including other authors, author contributions and affiliations, financial disclosures, funding and support, etc.