A longitudinal observational study of brain atrophy rate reflecting four decades of multiple sclerosis: a comparison of serial 1D, 2D, and volumetric measurements from MRI images

How does the brain age in individuals with multiple sclerosis? A systematic review

Multiple Sclerosis (MS) is a complex neurological disorder that involves demyelination, lesions and atrophy in both white and gray matter. Such changes in the central nervous system are diagnostic in MS and has a strong relationship with both physical and cognitive symptoms. As a result, magnetic resonance imaging (MRI) scans as a metric of brain atrophy have emerged as an important outcome measure in MS studies. Recently, research has begun to focus on the contribution of aging to the structural changes in the brain associated with MS; prompting questions about whether there is an amplifying effect of aging superimposed on MS-related brain atrophy. To examine current evidence of how the brain ages in individuals with MS, a systematic review of the literature was performed. Specific questions were focused on how aging affects gray and white matter structure, whether patterns of brain atrophy differ in younger and older cohorts and if there are structural differences in the brain as a function of sex in aging people with MS. This review considered studies that used MRI to examine the effects of aging in adults with MS. Twenty-one studies met eligibility criteria. Findings across these studies revealed that gray matter atrophy was more pronounced in older adults with MS, particularly in subcortical regions such as the thalamus; that the rates of atrophy were similar but varied by region for younger and older cohorts; and that males may experience more brain atrophy than females. Further studies that use multimodal MRI acquisition methods are needed to capture changes in both males and females over time, particularly in middle to older adulthood.

The association between brain volume loss and disability in multiple sclerosis: A systematic review

BACKGROUND

Multiple sclerosis (MS) is a chronic, inflammatory, demyelinating, degenerative disease of the central nervous system that affects approximately 2.8 million people worldwide. Compelling evidence from observational studies and clinical trials indicates a strong association between brain volume loss (BVL) and the accumulation of disability in MS. However, the considerable heterogeneity in study designs and methods of assessment of BVL invites questions concerning the generalizability of the reported findings. Therefore, we conducted this systematic review to characterize the relationship between BVL and physical disability in patients with MS.

METHODS

A systematic literature search of MEDLINE and EMBASE databases was performed supplemented by gray literature searches. The following study designs were included: prospective/retrospective cohort, cross-sectional and case-control. Only English language articles published from 2010 onwards were eligible for final inclusion. There were no restrictions on MS subtype, age, or ethnicity. Of the 1620 citations retrieved by the structured searches, 50 publications met our screening criteria and were included in the final data set.

RESULTS

Across all BVL measures, there was considerable heterogeneity in studies regarding the underlying study population, the definitions of BVL and image analysis methodologies, the physical disability measure used, the measures of association reported and whether the analysis conducted was univariable or multivariable. A total of 36 primary studies providing data on the association between whole BVL and physical disability in MS collectively suggest that whole brain atrophy is associated with greater physical disability progression in MS patients. Similarly, a total of 15 primary studies providing data on the association between ventricular atrophy and physical disability in MS suggest that ventricular atrophy is associated with greater physical disability progression in MS patients. Along similar lines, the existing evidence based on a total of 13 primary studies suggests that gray matter atrophy is associated with greater physical disability progression in MS patients. Four primary studies suggest that corpus callosum atrophy is associated with greater physical disability progression in MS patients. The majority of the existing evidence (6 primary studies) suggests no association between white matter atrophy and physical disability in MS. It is difficult to assign a relationship between basal ganglia volume loss and physical disability as well as medulla oblongata width and physical disability in MS due to very limited data.

CONCLUSION

The evidence gathered from this systematic review, although very heterogeneous, suggests that whole brain atrophy is associated with greater physical disability progression in MS patients. Our review can help define future imaging biomarkers for physical disability progression and treatment monitoring in MS.

Aging and Brain Atrophy in Multiple Sclerosis

BACKGROUND AND PURPOSE

Brain atrophy accelerates at the age of 60 in healthy individuals (HI) and at disease onset in multiple sclerosis (MS) patients. Whether there is an exacerbating effect of aging superimposed on MS-related brain atrophy is unknown. We estimated the aging effect on lateral ventricular volume (LVV) and whole brain volume (WBV) changes in MS patients.

METHODS

1,982 MS patients (mean follow-up: 4.8 years) and 351 HI (mean follow-up: of 3.1 years), aged from 20 to 79 years old (yo), were collected retrospectively. Percent LVV change (PLVVC) and percent brain volume change (PBVC) on 1.5T and 3T MRI scanners (median of 3.9 scans per subject) were calculated. These were determined between all-time points and subjects were divided in six-decade age groups. MRI differences between age groups were calculated using analysis of covariance (ANCOVA).

RESULTS

Compared to HI, at first MRI, MS patients had significantly increased LVV in the age groups: 30-39 yo, 40-49 yo, 50-59 yo, 60-69 yo (all P < .0001), and 70-79 yo (P = .029), and decreased WBV in the age groups: 20-29 yo (P = .024), 30-39 yo (P = .031), 40-49 yo, and 50-59 yo (all P < .0001). Annualized PLVVC was significantly different between the age groups 20-59 and 60-79 yo in MS patients (P = .005) and HI (P < .0001), as was for PBVC in MS patients (P = .001), but not for HI (P = .521). There was a significant aging interaction effect in the annualized PLVVC (P = .001) between HI and MS patients, which was not observed for the annualized PBVC (P = .380).

CONCLUSIONS

Development of brain atrophy manifests progressively in MS patients, and occurs with a different pattern, as compared to aging HI. PLVVC increased across age in HI as compared to MS, while PBVC decreased across ages in both HI and MS.

Structural MRI correlates of cognitive function in multiple sclerosis

BACKGROUND

Cognitive impairment (CI) has been associated with numerous magnetic resonance imaging (MRI) indices in multiple sclerosis (MS) patients. In this study we investigated the association of a large set of 2D and 3D MRI markers with cognitive function in MS.

METHODS

A sample of 61 RRMS patients (mean age 41.8 ± 10.6 years old, 44 women, mean disease duration 137.9 ± 83.9 months) along with 51 age and gender matched healthy controls was used in this cross-sectional study. Neuropsychological and other tests, along with a large set of 2D/3D MRI evaluations were made.

RESULTS

44.3% of patients had CI. CI patients had more disability, physical fatigue than non-CI patients and more psychological distress than non-CI patients and HCs. Also, CI patients had significantly larger third ventricle width and volume, smaller coprus callosum index and larger lesion volume than non-CI patients. These MRI markers also significantly predicted cognitive scores after adjusting for age and education, explaining about 30.6% of the variance of the total cognitive score.

CONCLUSIONS

Selected linear and volumetric MRI indices predict cognitive function in MS. Future studies should expand these results by exploring longitudinal changes and producing normative data.

Detection of Volume-Changing Metastatic Brain Tumors on Longitudinal MRI Using a Semiautomated Algorithm Based on the Jacobian Operator Field

BACKGROUND AND PURPOSE

Accurate follow-up of metastatic brain tumors has important implications for patient prognosis and management. The aim of this study was to develop and evaluate the accuracy of a semiautomated algorithm in detecting growing or shrinking metastatic brain tumors on longitudinal brain MRIs.

MATERIALS AND METHODS

We used 50 pairs of successive MR imaging datasets, 30 on 1.5T and 20 on 3T, containing contrast-enhanced 3D T1-weighted sequences. These yielded 150 growing or shrinking metastatic brain tumors. To detect them, we completed 2 major steps: 1) spatial normalization and calculation of the Jacobian operator field to quantify changes between scans, and 2) metastatic brain tumor candidate segmentation and detection of volume-changing metastatic brain tumors with the Jacobian operator field. Receiver operating characteristic analysis was used to assess the detection accuracy of the algorithm, and it was verified with jackknife resampling. The reference standard was based on detections by a neuroradiologist.

RESULTS

The areas under the receiver operating characteristic curves were 0.925 for 1.5T and 0.965 for 3T. Furthermore, at its optimal performance, the algorithm achieved a sensitivity of 85.1% and 92.1% and specificity of 86.7% and 91.3% for 1.5T and 3T, respectively. Vessels were responsible for most false-positives. Newly developed or resolved metastatic brain tumors were a major source of false-negatives.

CONCLUSIONS

The proposed algorithm could detect volume-changing metastatic brain tumors on longitudinal brain MRIs with statistically high accuracy, demonstrating its potential as a computer-aided change-detection tool for complementing the performance of radiologists, decreasing inter- and intraobserver variability, and improving efficacy.

The Role of T1-Weighted Derived Measures of Neurodegeneration for Assessing Disability Progression in Multiple Sclerosis

Introduction

Multiple sclerosis (MS) is characterised by the accumulation of permanent neurological disability secondary to irreversible tissue loss (neurodegeneration) in the brain and spinal cord. MRI measures derived from T1-weighted image analysis (i.e., black holes and atrophy) are correlated with pathological measures of irreversible tissue loss. Quantifying the degree of neurodegeneration in vivo using MRI may offer a surrogate marker with which to predict disability progression and the effect of treatment. This review evaluates the literature examining the association between MRI measures of neurodegeneration derived from T1-weighted images and disability in MS patients.

Methods

A systematic PubMed search was conducted in January 2017 to identify MRI studies in MS patients investigating the relationship between “black holes” and/or atrophy in the brain and spinal cord, and disability. Results were limited to human studies published in English in the previous 10 years.

Results

A large number of studies have evaluated the association between the previous MRI measures and disability. These vary considerably in terms of study design, duration of follow-up, size, and phenotype of the patient population. Most, although not all, have shown that there is a significant correlation between disability and black holes in the brain, as well as atrophy of the whole brain and grey matter. The results for brain white matter atrophy are less consistently positive, whereas studies evaluating spinal cord atrophy consistently showed a significant correlation with disability. Newer ways of measuring atrophy, thanks to the development of segmentation and voxel-wise methods, have allowed us to assess the involvement of strategic regions of the CNS (e.g., thalamus) and to map the regional distribution of damage. This has resulted in better correlations between MRI measures and disability and in the identification of the critical role played by some CNS structures for MS clinical manifestations.

Conclusion

The evaluation of MRI measures of atrophy as predictive markers of disability in MS is a highly active area of research. At present, measurement of atrophy remains within the realm of clinical studies, but its utility in clinical practice has been recognized and barriers to its implementation are starting to be addressed.

Clinical relevance of brain atrophy assessment in multiple sclerosis. Implications for its use in a clinical routine

INTRODUCTION

Brain atrophy measurement in multiple sclerosis (MS) has become an important outcome for determining patients at risk for developing physical and cognitive disability.

AREAS COVERED

In this article, we discuss the methodological issues related to using this MRI metric routinely, in a clinical setting. Understanding trajectories of annualized whole brain, gray and white matter, thalamic volume loss, and enlargement of ventricular space in specific MS phenotypes is becoming increasingly important. Evidence is mounting that disease-modifying treatments exert a positive effect on slowing brain atrophy progression in MS. Expert Commentary: While there is a need to translate measurement of brain atrophy to clinical routine at the individual patient level, there are still a number of challenges to be met before this can actually happen, including how to account for biological confounding factors and pseudoatrophy, standardize acquisition and analyses parameters, which can influence the accuracy of the assessments.

Decision-making under explicit risk is impaired in multiple sclerosis: relationships with ventricular width and disease disability

BACKGROUND

Decision-making is an essential function of everyday life. Decision-making under explicit risk requires developing advantageous decision strategies based on fixed outcomes (e.g., probabilities of winning or losing a bet). Decision-making and its neural substrates have been rarely studied in MS. We expected performance in decision-making under risk to be lowered in MS patients, and negatively correlated with disease-related disability, cognition, and ventricular width.

METHODS

Three groups were included: 32 MS patients and 20 healthy controls were examined with conventional neuropsychological tests and the Game-of-Dice Task (GDT) assessing decision-making under explicit risk. Linear 2-D ventricular width was assessed on MS patients' clinical MRIs and compared to a third group, 20 non-MS neurological control patients.

RESULTS

Compared to healthy controls, MS patients showed impaired GDT and neuropsychological performance, depending on the MS-subtype (relapsing-remitting (RR), n = 22; secondary progressive, n = 10) and disability severity among RR-MS patients. In MS patients, GDT performance correlated with processing speed, intercaudate ratio, and third ventricle ratio (p's < 0.05). Mediation analysis showed that the link between GDT performance and processing speed was fully explained by ventricular size.

CONCLUSION

Decision-making under explicit risk was reduced in MS patients, but only those with more pronounced disability. Independent of processing speed, decision-making under explicit risk correlates inversely with central atrophy in MS.

Sub-millimeter imaging of brain-free water for rapid volume assessment in atrophic brains

INTRODUCTION

Cerebral atrophy occurs in healthy aging, and in disease processes such as multiple sclerosis (MS), it correlates with disability accumulation. Imaging measurements of brain atrophy are commonly based on tissue segmentation, which is susceptible to classification errors and inconsistencies. High-resolution imaging techniques with strong contrast between brain parenchyma and cerebrospinal fluid (CSF) might allow fully automated, rapid, threshold-based determination of the free water in the brain. We hypothesized that total brain-free-water (BFW) volume and BFW volume expressed as a normalized fraction of the intracranial volume ("BFW fraction"), determined from heavily T2-weighted images, would be useful surrogates for cerebral atrophy and therefore would correlate with clinical measures of disability in MS.

METHODS

Whole brains of 83 MS cases and 7 healthy volunteers were imaged with a 4.7-min, heavily T2-weighted sequence on a 3T MRI scanner, acquiring 650-μm isotropic voxels. MS cases were clinically assessed on the Expanded Disability Status Scale (EDSS), Scripps Neurological Rating Scale (SNRS), Paced Auditory Serial Addition Test (PASAT), 9-Hole Peg Test (9HPT), Symbol Digit Modalities Test (SDMT), and 25-Foot Timed Walk. Twelve of the MS cases were rescanned within an average of 1.8 months to assess reproducibility. Automated calculations of BFW volume and BFW fraction were correlated with clinical measures of disability upon adjusting for age and sex. Results were compared to data from T1-based approaches (SIENAX and Lesion-TOADS).

RESULTS AND DISCUSSION

BFW volume was automatically derived from heavily T2-weighted images with no need for separate skull stripping. BFW volume and fraction had mean scan-rescan coefficients of variation of 1.5% and 1.9%, respectively, similar to the T1-based approaches tested here. BFW fraction more strongly correlated with clinical measures than T1-derived results. Among those clinical measures, modality-specific disability scores, such as SDMT and 9HPT, were more strongly associated with BFW fraction than composite measures, such as EDSS and SNRS.

CONCLUSION

The BFW method robustly estimates cerebral atrophy in an automated, fast, and reliable manner, and as such may prove a useful addition to imaging protocols for clinical practice and trials.

Quantification of multiple-sclerosis-related brain atrophy in two heterogeneous MRI datasets using mixed-effects modeling

Brain atrophy, measured by MRI, has been proposed as a useful surrogate marker for disease progression in multiple sclerosis (MS). However, it is conventionally assumed that the accurate quantification of brain atrophy is made difficult, if not impossible, by changes in the parameters of the MRI acquisition, which are almost inevitable over the course of a longitudinal study since MRI technology changes rapidly. This state of affairs can negatively affect clinical trial design and limit the use of historical data. Here, we investigate whether we can coherently estimate brain atrophy rates in a heterogeneous MS sample via linear mixed-effects multivariable regression, incorporating three critical assumptions: (1) using age at time of scanning, rather than time since baseline, as the regressor of interest; (2) scanning individuals with a variety of techniques; and (3) introducing a simple additive correction for major differences in MRI protocol. We fit the model to several measures of brain volume as the outcome in two MS populations: 1123 scans from 195 cases acquired for over approximately 7 years in two natural history protocols (Cohort 1), and 1331 scans from 69 cases seen for over 11 years who were primarily treated with two specific MS disease-modifying therapies (Cohort 2). We compared the mixed-effects model with additive correction for MRI acquisition parameters to a model fit without this correction and performed sample-size calculations to provide an estimate of the number of participants in an MS clinical trial that might be required to see a therapeutic effect of treatment using the approach described here. The results show that without the additive correction for T1-weighted protocol parameters, atrophy was underestimated and subject-specific estimates were more narrowly distributed about the population mean. Ventricular CSF is the most consistently estimated brain volume, with a mean of 2.8%/year increase in Cohort 1 and 4.4%/year increase in Cohort 2. An interesting observation was that gray matter volume decreased and white matter volume remained essentially unchanged in both cohorts, suggesting that changes in ventricular CSF volume are a surrogate for changes in gray matter volume. In conclusion, the mixed-effects modeling framework presented here allows effective use of heterogeneously acquired and historical data in the study of brain atrophy in MS, potentially simplifying the design of future single- and multi-site clinical trials and natural history studies.

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We model brain atrophy in two heterogeneously acquired MS MRI datasets.

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Mixed-effects regression effectively adjusts for major MRI differences.

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Ventricular CSF tracks with gray matter but is more reliably estimated.

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The method would allow reasonable sample sizes in MS therapeutic trials.

Increased concentrations of glutamate and glutamine in normal-appearing white matter of patients with multiple sclerosis and normal MR imaging brain scans

In Multiple Sclerosis (MS) the relationship between disease process in normal-appearing white matter (NAWM) and the development of white matter lesions is not well understood. In this study we used single voxel proton 'Quantitative Magnetic Resonance Spectroscopy' (qMRS) to characterize the NAWM and thalamus both in atypical 'Clinically Definite MS' (CDMS) patients, MRI(neg) (N = 15) with very few lesions (two or fewer lesions), and in typical CDMS patients, MRI(pos) (N = 20) with lesions, in comparison with healthy control subjects (N = 20). In addition, the metabolite concentrations were also correlated with extent of brain atrophy measured using Brain Parenchymal Fraction (BPF) and severity of the disease measured using 'Multiple Sclerosis Severity Score' (MSSS). Elevated concentrations of glutamate and glutamine (Glx) were observed in both MS groups (MRI(neg) 8.12 mM, p<0.001 and MRI(pos) 7.96 mM p<0.001) compared to controls, 6.76 mM. Linear regressions of Glx and total creatine (tCr) with MSSS were 0.16 ± 0.06 mM/MSSS (p = 0.02) for Glx and 0.06 ± 0.03 mM/MSSS (p = 0.04) for tCr, respectively. Moreover, linear regressions of tCr and myo-Inositol (mIns) with BPF were -6.22 ± 1.63 mM/BPF (p<0.001) for tCr and -7.71 ± 2.43 mM/BPF (p = 0.003) for mIns. Furthermore, the MRI(pos) patients had lower N-acetylaspartate and N-acetylaspartate-glutamate (tNA) and elevated mIns concentrations in NAWM compared to both controls (tNA: p = 0.04 mIns p<0.001) and MRI(neg) (tNA: p = 0.03 , mIns: p = 0.002). The results suggest that Glx may be an important marker for pathology in non-lesional white matter in MS. Moreover, Glx is related to the severity of MS independent of number of lesions in the patient. In contrast, increased glial density indicated by increased mIns and decreased neuronal density indicated by the decreased tNA, were only observed in NAWM of typical CDMS patients with white matter lesions.

Evolution of cortical and thalamus atrophy and disability progression in early relapsing-remitting MS during 5 years

BACKGROUND AND PURPOSE

Pathologic changes in GM have an important role in MS. We investigated the association between SDGM and cortical volume changes and disability progression in early RRMS.

MATERIALS AND METHODS

One hundred eighty patients with RRMS had clinical assessment during 5 years and were divided into those with or without SDP at 5 years by the usual definition in treatment trials. The number of available MR imaging scans at various time points was the following: at baseline, 178; and at 6 months, 172; at 12 months, 175; at 24 months, 155; at 36 months, 160; at 48 months, 158; and at 60 months, 162, respectively. Longitudinal changes in cortical, GM, and WM volume were calculated by using the direct method.

RESULTS

At 5 years, 90 patients with RRMS experienced SDP and 90 had stable disease. At baseline, patients with SDP had longer disease duration, greater T2-lesion volume, and smaller whole-brain, WM, cortical, and SDGM volume (P < .01). At 5 years, patients with SDP had significantly greater percentage decreases from baseline compared with those without SDP in the volume of the whole brain (P < .0001), cortex (P = .001), GM (P = .003), and thalamus (P = .01). In patients who developed SDP at 5 years and those who did not, mixed-effect models, adjusted for age, disease duration, and change of the treatment status, showed significant interactions between SDP status at 5 years and changes with time in whole-brain, cortical, lateral ventricle (all P < .001), thalamus (P = .006), and total SDGM (P = .0095) volume.

CONCLUSIONS

SDP is associated with progression of cortical, central, and thalamic atrophy in early RRMS during 5 years.

Oligoclonal bands in the cerebrospinal fluid and increased brain atrophy in early stages of relapsing-remitting multiple sclerosis

OBJECTIVE

To determine if the presence of oligoclonal bands (OB) at early stages of multiple sclerosis was associated with higher brain atrophy, when compared with patients without OB.

METHODS

Relapsing-remitting multiple sclerosis (RRMS) patients with less than two years of disease onset and OB detection in cerebrospinal fluid (CSF) were included. SIENAX was used for total brain volume (TBV), gray matter volume (GMV), and white matter volume (WMV).

RESULTS

Forty patients were included, 29 had positive IgG-OB. No differences were found between positive and negative patients in gender, expanded disability status scale (EDSS), treatment received, and T2/T1 lesion load. TBV in positive IgG-OB patients was 1.5 mm³ x 10(6) compared with 1.64 mm³ x 10(6) in the negative ones (p=0.02). GMV was 0.51 mm³ x 10(6) in positive IgG-OB compared with 0.62 mm³ x 10(6) in negative ones (p=0.002). No differences in WMV (p=0.09) were seen.

CONCLUSIONS

IgG-OB in the CSF was related to neurodegeneration magnetic resonance (MR) markers in early RRMS.

Deficient MWF mapping in multiple sclerosis using 3D whole-brain multi-component relaxation MRI

Recent multiple sclerosis (MS) MRI research has highlighted the need to move beyond the lesion-centric view and to develop and validate new MR imaging strategies that quantify the invisible burden of disease in the brain and establish much more sensitive and specific surrogate markers of clinical disability. One of the most promising of such measures is myelin-selective MRI that allows the acquisition of myelin water fraction (MWF) maps, a parameter that is correlated to brain white matter (WM) myelination. The aim of our study was to apply the newest myelin-selective MRI method, multi-component Driven Equilibrium Single Pulse Observation of T1 and T2 (mcDESPOT) in a controlled clinical MS pilot trial. This study was designed to assess the capabilities of this new method to explain differences in disease course and degree of disability in subjects spanning a broad spectrum of MS disease severity. The whole-brain isotropically-resolved 3D acquisition capability of mcDESPOT allowed for the first time the registration of 3D MWF maps to standard space, and consequently a formalized voxel-based analysis of the data. This approach combined with image segmentation further allowed the derivation of new measures of MWF deficiency: total deficient MWF volume (DV) in WM, in WM lesions, in diffusely abnormal white matter and in normal appearing white matter (NAWM). Deficient MWF volume fraction (DVF) was derived from each of these by dividing by the corresponding region volume. Our results confirm that lesion burden does not correlate well with clinical disease activity measured with the extended disability status scale (EDSS) in MS patients. In contrast, our measurements of DVF in NAWM correlated significantly with the EDSS score (R2=0.37; p<0.001). The same quantity discriminated clinically isolated syndrome patients from a normal control population (p<0.001) and discriminated relapsing-remitting from secondary-progressive patients (p<0.05); hence this new technique may sense early disease-related myelin loss and transitions to progressive disease. Multivariate analysis revealed that global atrophy, mean whole-brain myelin water fraction and white matter atrophy were the three most important image-derived parameters for predicting clinical disability (EDSS). Overall, our results demonstrate that mcDESPOT-defined measurements in NAWM show great promise as imaging markers of global clinical disease activity in MS. Further investigation will determine if this measure can serve as a risk factor for the conversion into definite MS and for the secondary transition into irreversible disease progression.

A putative Alzheimer's disease risk allele in PCK1 influences brain atrophy in multiple sclerosis

Background

Brain atrophy and cognitive dysfunction are neurodegenerative features of Multiple Sclerosis (MS). We used a candidate gene approach to address whether genetic variants implicated in susceptibility to late onset Alzheimer's Disease (AD) influence brain volume and cognition in MS patients.

Methods/Principal Findings

MS subjects were genotyped for five single nucleotide polymorphisms (SNPs) associated with susceptibility to AD: PICALM, CR1, CLU, PCK1, and ZNF224. We assessed brain volume using Brain Parenchymal Fraction (BPF) measurements obtained from Magnetic Resonance Imaging (MRI) data and cognitive function using the Symbol Digit Modalities Test (SDMT). Genotypes were correlated with cross-sectional BPF and SDMT scores using linear regression after adjusting for sex, age at symptom onset, and disease duration. 722 MS patients with a mean (±SD) age at enrollment of 41 (±10) years were followed for 44 (±28) months. The AD risk-associated allele of a non-synonymous SNP in the PCK1 locus (rs8192708^G) is associated with a smaller average brain volume (P = 0.0047) at the baseline MRI, but it does not impact our baseline estimate of cognition. PCK1 is additionally associated with higher baseline T2-hyperintense lesion volume (P = 0.0088). Finally, we provide technical validation of our observation in a subset of 641 subjects that have more than one MRI study, demonstrating the same association between PCK1 and smaller average brain volume (P = 0.0089) at the last MRI visit.

Conclusion/Significance

Our study provides suggestive evidence for greater brain atrophy in MS patients bearing the PCK1 allele associated with AD-susceptibility, yielding new insights into potentially shared neurodegenerative process between MS and late onset AD.

Cerebral and cerebellar volume loss in children and adolescents with systemic lupus erythematosus: a review of clinically acquired brain magnetic resonance imaging

OBJECTIVE

Cerebral atrophy is a prominent feature in adults with systemic lupus erythematosus (SLE). We assessed cerebral and cerebellar volume loss on clinically acquired brain magnetic resonance imaging (MRI) scans of children and adolescents with SLE.

METHODS

We abstracted information on disease course for patients who underwent clinical brain MRI during the period 2002-2008. We completed qualitative assessments of volume loss and measured corpus callosum thickness and ventricular enlargement for patients with lupus and controls.

RESULTS

Forty-nine children underwent brain MRI during the review period due to clinical indications. The lupus cohort was predominantly female and ethnically diverse. Mean age at imaging was 15.3 +/- 2.6 years and mean disease duration was 30.6 +/- 33.3 months. Findings suggestive of cerebral and cerebellar volume loss were seen respectively in 89.8% and 91.8% of lupus patients. Cerebral volume loss was moderate or severe in 26.5% of children. Cerebellar volume loss was moderate in 20.4% of these patients. Linear measurement means reflected corpus callosum thinning and ventricular enlargement in lupus patients. Volume loss was observed in newly diagnosed patients prior to corticosteroid use. Disease duration and corticosteroid use did not predict the severity of volume loss. There were statistically significant differences in linear imaging measurements comparing lupus patients to 14 similar-age controls.

CONCLUSION

Regional volume loss was observed in most adolescents with lupus undergoing clinical brain MRI scans. As in other pediatric conditions with inflammatory or vascular etiologies, these findings may be reflecting disease-associated neuronal loss and not solely the effects of corticosteroid.