Thoracic spinal cord lesions are influenced by the degree of cervical spine involvement in multiple sclerosis.

STUDY DESIGN: Cross-sectional analyses. OBJECTIVE: To determine whether cervical spinal cord lesions predict the presence of thoracic cord lesions in multiple sclerosis (MS) patients. SETTING: Single MS Clinic, AZ, USA. METHODS: All MS patients, with MRI studies of the brain, cervical and thoracic spine obtained during a single scanning session, were acquired during a 1-year period. Clinical, demographic and imaging covariates were used in a multivariate regression model to refine predictors of thoracic cord involvement. RESULTS: A total of 687 patients were evaluated, and patients were excluded because of a diagnosis of other neurological disorders, not meeting the 2010 McDonald criteria for MS (n=222) or incomplete neuraxis imaging (n=339). The study cohort comprised 126 patients. There was an increase in the odds ratio (OR) of thoracic spine involvement when any cervical spine lesion was present (OR=6.08, 95% confidence interval (2.21-16.68), P<0.001). The multivariate logistic regression model demonstrated a substantial and significant increase in the odds of thoracic spine involvement when more than two cervical spine lesions were present, two lesions (OR 4.44, (0.91-21.60), P=0.06), three lesions (OR 19.76, (3.51-111.17), P=0.001), four or more lesions (OR 20.49, (1.97-213.23), P=0.012) and diffuse lesions (OR 71.94, (5.28-979.88), P=0.001), when adjusting for significant covariates including clinical symptoms, brain lesions, disease duration and treatment exposure. CONCLUSIONS: Thoracic spinal cord lesions appear to be predicated on the degree of cervical spine involvement in patients with MS, a risk that appears to be independent of brain findings or clinical features.

Impact of pregnancy on conversion to clinically isolated syndrome in a radiologically isolated syndrome cohort.

BACKGROUND: In multiple sclerosis (MS), the relapse rate declines during pregnancy and increases during the first three months post-partum before returning to the pre-pregnancy rate. It is unknown whether pregnancy impacts the risk of clinical conversion in those within the presymptomatic period. OBJECTIVES: We investigate the impact of pregnancy on developing a clinical event in women diagnosed with radiologically isolated syndrome (RIS). METHODS: All women with RIS underwent clinical and radiological assessments as part of an observational, prospective, longitudinal study. Clinical and MRI outcomes were analyzed during and after pregnancy. Subjects who became pregnant were compared with an age-matched female RIS group who did not become pregnant during the same follow-up period. RESULTS: A total of 60 women with RIS were followed for up to seven years. Among them, seven became pregnant and were compared with 53 age-matched control women with RIS who did not become pregnant during the observation period. A significantly shorter time of conversion to the first neurological event was observed in the pregnant group [15.3 months (10-18)] compared with the non-pregnant controls [35.7 months (8-76)], yielding an absolute difference of 20.4 months (p<0.05). The mean (SD) number of active lesions on a subsequent brain MRI scan was significantly higher in the pregnant group [3.2 (±1.7)] compared with the control group [1.8 (±0.6)]. CONCLUSIONS: The risk for clinical conversion from RIS to a clinical event and new MRI disease activity seems to be influenced by pregnancy. Pregnancy related physiological changes could operate as early as the presymptomatic period in patients with MS.

Asymptomatic spinal cord lesions predict disease progression in radiologically isolated syndrome.

BACKGROUND: Technological advancements in neuroimaging and the increased use of these diagnostic modalities are responsible for the discovery of incidentally identified anomalies within the CNS. In addition to the identification of unanticipated brain MRI abnormalities suggestive of demyelinating disease in patients undergoing neuroimaging for a medical reason other than evaluation for multiple sclerosis (MS), asymptomatic spinal cord lesions are periodically identified. OBJECTIVE: To determine if asymptomatic spinal cord lesions are associated with clinical progression in subjects with radiologically isolated syndrome (RIS). METHODS: A retrospective review of RIS cases at the University of California, San Francisco Multiple Sclerosis Center was performed. The presence of asymptomatic cervical spinal cord MRI lesions was analyzed as a potential predictor for clinical progression. RESULTS: Twenty-five of 71 subjects with RIS possessed findings within the cervical spine that were highly suggestive of demyelinating disease. Of these subjects, 21 (84%) progressed clinically to clinically isolated syndrome (n = 19) or primary progressive multiple sclerosis (n = 2) over a median time of 1.6 years from the date of RIS identification (interquartile range 0.8-3.8). The sensitivity, specificity, and positive predictive value of an asymptomatic spinal cord lesion for subsequent development of either a first demyelinating attack or primary progressive MS were 87.5%, 91.5%, and 84%, respectively. The odds ratio of clinical progression was 75.3 (95% confidence interval 16.1-350.0, p < 0.0001). This association remained significant after adjusting for potential confounders. CONCLUSION: These findings suggest that the presence of asymptomatic spinal cord lesions place subjects with RIS at substantial risk for clinical conversion to either an acute or progressive event, a risk that is independent of brain lesions on MRI.

Quality of life in multiple sclerosis is associated with lesion burden and brain volume measures.

BACKGROUND: Health-related quality of life (HRQOL) is reduced in multiple sclerosis (MS). It is unclear whether HRQOL is associated with white matter lesion burden or measures of brain atrophy. METHODS: A cross-sectional baseline analysis of 507 patients with MS in a prospective cohort study at the University of California, San Francisco was performed. Multivariate linear regression models were used to determine whether MRI measures were associated with the Emotional Well-Being and Thinking/Fatigue subscale scores of the Functional Assessment in Multiple Sclerosis, a validated HRQOL measure in MS. The difference in each MRI metric associated with a minimal clinically important difference in each HRQOL subscale was calculated. RESULTS: Higher T1 lesion load (15 mL; p = 0.024), normalized T1 lesion volume (20 mL; p = 0.016), or T2 lesion load (25 mL; p = 0.028) was associated with worse scores for Emotional Well-Being. Meaningfully lower scores on this subscale were correlated with lower normalized gray matter volume (118 mL; p = 0.037). Reduced Thinking/Fatigue scores were associated with higher normalized T1 lesion volume (21 mL; p = 0.024), or T2 lesion load (22 mL; p = 0.010) and with lower normalized gray matter (87 mL; p = 0.004), white matter (85 mL; p = 0.025), or brain parenchymal (98 mL; p = 0.001) volume. CONCLUSIONS: Aspects of health-related quality of life (HRQOL) in multiple sclerosis are associated with MRI evidence of white matter lesions and brain atrophy. These findings strengthen the argument for the use of HRQOL outcome measures in trials and suggest that lesion burden on conventional MRI is important for HRQOL.

Genotype-Phenotype correlations in multiple sclerosis: HLA genes influence disease severity inferred by 1HMR spectroscopy and MRI measures.

Genetic susceptibility to multiple sclerosis (MS) is associated with the human leukocyte antigen (HLA) DRB1*1501 allele. Here we show a clear association between DRB1*1501 carrier status and four domains of disease severity in an investigation of genotype-phenotype associations in 505 robust, clinically well characterized MS patients evaluated cross-sectionally: (i) a reduction in the N-acetyl-aspartate (NAA) concentration within normal appearing white matter (NAWM) via (1)HMR spectroscopy (P = 0.025), (ii) an increase in the volume of white matter (WM) lesions utilizing conventional anatomical MRI techniques (1,127 mm(3); P = 0.031), (iii) a reduction in normalized brain parenchymal volume (nBPV) (P = 0.023), and (iv) impairments in cognitive function as measured by the Paced Auditory Serial Addition Test (PASAT-3) performance (Mean Z Score: DRB1*1501+: 0.110 versus DRB1*1501-: 0.048; P = 0.004). In addition, DRB1*1501+ patients had significantly more women (74% versus 63%; P = 0.009) and a younger mean age at disease onset (32.4 years versus 34.3 years; P = 0.025). Our findings suggest that DRB1*1501 increases disease severity in MS by facilitating the development of more T2-foci, thereby increasing the potential for irreversible axonal compromise and subsequent neuronal degeneration, as suggested by the reduction of NAA concentrations in NAWM, ultimately leading to a decline in brain volume. These structural aberrations may explain the significant differences in cognitive performance observed between DRB1*1501 groups. The overall goal of a deep phenotypic approach to MS is to develop an array of meaningful biomarkers to monitor the course of the disease, predict future disease behaviour, determine when treatment is necessary, and perhaps to more effectively recommend an available therapeutic intervention.

Incidental MRI anomalies suggestive of multiple sclerosis: the radiologically isolated syndrome.

BACKGROUND: The discovery and broad application of MRI in medicine has led to an increased awareness in the number of patients with incidental white matter pathology in the CNS. Routinely encountered in clinical practice, the natural history or evolution of such individuals with respect to their risk of developing multiple sclerosis (MS) is unclear. OBJECTIVE: To investigate the natural history of patients who exhibit incidental imaging findings highly suggestive of MS pathology. METHODS: Detailed clinical and radiologic data were obtained from asymptomatic patients with MRI anomalies suggestive of MS. RESULTS: The cohort consisted of 41 female and 3 male subjects (median age = 38.5, range: 16.2-67.1). Clinical evaluations were performed in 44 patients at the time of initial imaging; longitudinal clinical follow-up occurred for 30 patients, and longitudinal MRI data were acquired for 41 patients. Neurologic examination at the time of the initial MRI scans was normal in nearly all cases. While radiologic progression was identified in 59% of cases, only 10 patients converted to either clinically isolated syndrome or definite MS. The presence of contrast-enhancing lesions on the initial MRI was predictive of dissemination in time on repeat imaging of the brain (hazard ratio [HR] = 3.4, 95% confidence interval [1.3, 8.7], p = 0.01). CONCLUSION: Individuals with MRI anomalies highly suggestive of demyelinating pathology, not better accounted for by another disease process, are very likely to experience subsequent radiologic or clinical events related to multiple sclerosis. Additional studies will be necessary to fully define this risk.

Regional grey matter atrophy in clinically isolated syndromes at presentation.

BACKGROUND: The presence and degree of neuronal degeneration already existing in patients at their initial presentation with a clinically isolated syndrome suggestive of multiple sclerosis (CIS) is unclear, and whole brain or whole normalised grey matter analyses have not demonstrated significant atrophy in CIS cohorts at clinical presentation. Voxel-based analyses allow detection of regional atrophy throughout the brain and, therefore, may be sensitive to regional atrophy in CIS patients, and these changes may correspond with clinical disability. METHODS: This study used a modified voxel-based morphometry (VBM) method to correct for lesion effects to analyse regional atrophy and perform voxel-wise correlations between volume and clinical metrics in 41 untreated CIS patients at presentation compared with 49 healthy controls. RESULTS: The results confirmed that there was no significant difference in whole normalised grey matter volume between CIS and controls, whereas VBM showed significant areas of bilateral thalamic, hypothalamic, putamen and caudate atrophy. Voxel-wise correlations with clinical measures showed that cerebellar volumes correlated with clinical cerebellar function, nine-hole peg test scores and the Multiple Sclerosis Functional Composite (MSFC) score, and that the MSFC score was also correlated with putamen volume. Lastly, T1 lesion volumes were found to correlate with thalamic and hippocampal atrophy, suggesting a link between white matter lesions and grey matter degeneration at the earliest stages of multiple sclerosis. CONCLUSIONS: Atrophy is present in CIS patients at presentations, particularly in the thalamus, and other deep grey matter structures. Furthermore, the correlations with clinical metrics suggest the importance of this atrophy to clinical status and the correlation with T1 lesion load suggests a possible role of Wallerian degeneration.