Determinants of cerebral atrophy rate at the time of diagnosis of multiple sclerosis.

OBJECTIVE To identify determinants visible on magnetic resonance imaging of the brain that explain the subsequent rate of cerebral atrophy in patients with recently diagnosed multiple sclerosis. DESIGN Magnetic resonance imaging of the brain was performed at baseline and after 2 years. T2 hyperintense lesion load, black hole lesion load, presence of contrast-enhancing lesions, and normalized brain volume were derived from the baseline magnetic resonance imaging and considered as possible explanatory variables for the subsequent annualized percentage of brain volume change (PBVC/y) using forward stepwise multiple linear regression analysis. SETTING MS center Amsterdam, Department of Neurology, VU University Medical Center, Amsterdam, the Netherlands. Patients Eighty-nine patients recently diagnosed as having multiple sclerosis were included at the time of diagnosis from our outpatient clinic. Main Outcome Measure Annualized percentage of brain volume change. RESULTS The mean (SD) annualized rate of cerebral atrophy was -0.9 (0.8) PBVC/y. Baseline normalized brain volume (standardized coefficient, 0.426; P = .001) and baseline T2 lesion load (standardized coefficient, -0.244; P = .02) were identified as explanatory variables for subsequent PBVC/y and yielded a regression model that explained 31.2% of the variance in PBVC/y. CONCLUSIONS In patients with recently diagnosed multiple sclerosis, the extent of accumulated brain tissue loss and overall lesion load partly explain the subsequent rate of cerebral atrophy.