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Chitnis, Tanuja

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Chitnis

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Tanuja

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Chitnis, Tanuja

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  • Publication

    Assessment of Definitions of Sustained Disease Progression in Relapsing-Remitting Multiple Sclerosis

    (Hindawi Publishing Corporation, 2013) Healy, Brian; Engler, David; Glanz, Bonnie; Musallam, Alexander; Chitnis, Tanuja

    Sustained progression on the expanded disability status scale (EDSS) is a common outcome measure of disease progression in clinical studies of MS. Unfortunately, this outcome may not accurately measure long-term and irreversible disease progression. To assess the performance of definitions of sustained progression, patients with relapsing-remitting MS (RRMS) or a clinically isolated syndrome with evidence of lesions on a brain MRI were included in our study. Fifteen definitions of sustained progression using both the EDSS and the functional system (FS) scales were investigated. The impact of both relapses and changes in provider on the probability of maintaining progression was also evaluated. Although the provider scoring the EDSS sometimes changed during followup, the provider had access to previous EDSS scores. Between 15.8% and 42.2% of patients experienced sustained progression based on the definitions using EDSS as the outcome, but nearly 50% of these patients failed to maintain sustained progression for the duration of followup. When FS scales were used, progression was most common on the pyramidal and sensory scales. Unfortunately, progression on specific FS scales failed to be more sensitive to irreversible disability. Relapses or changes in provider did not explain the poor performance of the measures. Short-term changes in the EDSS or FS scores may not be an accurate marker of irreversible change in RRMS.

  • Publication

    Evaluation of an Online Platform for Multiple Sclerosis Research: Patient Description, Validation of Severity Scale, and Exploration of BMI Effects on Disease Course

    (Public Library of Science, 2013) Musallam, Alexander; Vaughan, Timothy; Wicks, Paul; Bove, Riley; Secor, Elizabeth; Healy, Brian; Glanz, Bonnie; Greeke, Emily Elizabeth; Weiner, Howard; Chitnis, Tanuja; De Jager, Philip

    Objectives: To assess the potential of an online platform, PatientsLikeMe.com (PLM), for research in multiple sclerosis (MS). An investigation of the role of body mass index (BMI) on MS disease course was conducted to illustrate the utility of the platform. Methods: First, we compared the demographic characteristics of subjects from PLM and from a regional MS center. Second, we validated PLM’s patient-reported outcome measure (MS Rating Scale, MSRS) against standard physician-rated tools. Finally, we analyzed the relation of BMI to the MSRS measure. Results: Compared with 4,039 MS Center patients, the 10,255 PLM members were younger, more educated, and less often male and white. Disease course was more often relapsing remitting, with younger symptom onset and shorter disease duration. Differences were significant because of large sample sizes but small in absolute terms. MSRS scores for 121 MS Center patients revealed acceptable agreement between patient-derived and physician-derived composite scores (weighted kappa = 0.46). The Walking domain showed the highest weighted kappa (0.73) and correlation (rs = 0.86) between patient and physician scores. Additionally, there were good correlations between the patient-reported MSRS composite and walking scores and physician-derived measures: Expanded Disability Status Scale (composite rs = 0.61, walking rs = 0.74), Timed 25 Foot Walk (composite rs = 0.70, walking rs = 0.69), and Ambulation Index (composite rs = 0.81, walking rs = 0.84). Finally, using PLM data, we found a modest correlation between BMI and cross-sectional MSRS (rho = 0.17) and no association between BMI and disease course. Conclusions: The PLM population is comparable to a clinic population, and its patient-reported MSRS is correlated with existing clinical instruments. Thus, this online platform may provide a venue for MS investigations with unique strengths (frequent data collection, large sample sizes). To illustrate its applicability, we assessed the role of BMI in MS disease course but did not find a clinically meaningful role for BMI in this setting.

  • Publication

    Modeling Disease Severity in Multiple Sclerosis Using Electronic Health Records

    (Public Library of Science, 2013) Xia, Zongqi; Secor, Elizabeth; Chibnik, Lori; Bove, Riley; Cheng, Suchun; Chitnis, Tanuja; Cagan, Andrew; Gainer, Vivian S.; Chen, Pei J.; Liao, Katherine; Shaw, Stanley; Ananthakrishnan, Ashwin; Szolovits, Peter; Weiner, Howard; Karlson, Elizabeth; Murphy, Shawn; Savova, Guergana; Cai, Tianxi; Churchill, Susanne E.; Plenge, Robert M.; Kohane, Isaac; De Jager, Philip

    Objective: To optimally leverage the scalability and unique features of the electronic health records (EHR) for research that would ultimately improve patient care, we need to accurately identify patients and extract clinically meaningful measures. Using multiple sclerosis (MS) as a proof of principle, we showcased how to leverage routinely collected EHR data to identify patients with a complex neurological disorder and derive an important surrogate measure of disease severity heretofore only available in research settings. Methods: In a cross-sectional observational study, 5,495 MS patients were identified from the EHR systems of two major referral hospitals using an algorithm that includes codified and narrative information extracted using natural language processing. In the subset of patients who receive neurological care at a MS Center where disease measures have been collected, we used routinely collected EHR data to extract two aggregate indicators of MS severity of clinical relevance multiple sclerosis severity score (MSSS) and brain parenchymal fraction (BPF, a measure of whole brain volume). Results: The EHR algorithm that identifies MS patients has an area under the curve of 0.958, 83% sensitivity, 92% positive predictive value, and 89% negative predictive value when a 95% specificity threshold is used. The correlation between EHR-derived and true MSSS has a mean R2 = 0.38±0.05, and that between EHR-derived and true BPF has a mean R2 = 0.22±0.08. To illustrate its clinical relevance, derived MSSS captures the expected difference in disease severity between relapsing-remitting and progressive MS patients after adjusting for sex, age of symptom onset and disease duration (p = 1.56×10−12). Conclusion: Incorporation of sophisticated codified and narrative EHR data accurately identifies MS patients and provides estimation of a well-accepted indicator of MS severity that is widely used in research settings but not part of the routine medical records. Similar approaches could be applied to other complex neurological disorders.

  • Publication

    Alterations of the human gut microbiome in multiple sclerosis

    (Nature Publishing Group, 2016) Jangi, Sushrut; Gandhi, Roopali; Cox, Laura; Li, Ning; von Glehn, Felipe; Yan, Raymond; Patel, Bonny; Mazzola, Maria; Liu, Shirong; Glanz, Bonnie; Cook, Sandra; Tankou, Stephanie; Stuart, Fiona; Melo, Kirsy; Nejad, Parham; Smith, Kathleen; Topçuolu, Begüm D.; Holden, James; Kivisakk, Pia; Chitnis, Tanuja; De Jager, Philip; Quintana, Francisco; Gerber, Georg; Bry, Lynn; Weiner, Howard

    The gut microbiome plays an important role in immune function and has been implicated in several autoimmune disorders. Here we use 16S rRNA sequencing to investigate the gut microbiome in subjects with multiple sclerosis (MS, n=60) and healthy controls (n=43). Microbiome alterations in MS include increases in Methanobrevibacter and Akkermansia and decreases in Butyricimonas, and correlate with variations in the expression of genes involved in dendritic cell maturation, interferon signalling and NF-kB signalling pathways in circulating T cells and monocytes. Patients on disease-modifying treatment show increased abundances of Prevotella and Sutterella, and decreased Sarcina, compared with untreated patients. MS patients of a second cohort show elevated breath methane compared with controls, consistent with our observation of increased gut Methanobrevibacter in MS in the first cohort. Further study is required to assess whether the observed alterations in the gut microbiome play a role in, or are a consequence of, MS pathogenesis.

  • Publication

    Female hormonal exposures and neuromyelitis optica symptom onset in a multicenter study

    (Lippincott Williams & Wilkins, 2017) Bove, Riley; Elsone, Liene; Alvarez, Enrique; Borisow, Nadja; Cortez, Melissa M.; Mateen, Farrah; Mealy, Maureen A.; Mutch, Kerry; Tobyne, Sean; Ruprecht, Klemens; Buckle, Guy; Levy, Michael; Wingerchuk, Dean M.; Paul, Friedemann; Cross, Anne H.; Weinshenker, Brian; Jacob, Anu; Klawiter, Eric; Chitnis, Tanuja

    Objective: To study the association between hormonal exposures and disease onset in a cohort of women with neuromyelitis optica spectrum disorder (NMOSD). Methods: Reproductive history and hormone use were assessed using a standardized reproductive survey administered to women with NMOSD (82% aquaporin-4 antibody positive) at 8 clinical centers. Using multivariable regression, we examined the association between reproductive exposures and age at first symptom onset (FS). Results: Among 217 respondents, the mean age at menarche was 12.8 years (SD 1.7). The mean number of pregnancies was 2.1 (SD 1.6), including 0.3 (SD 0.7) occurring after onset of NMOSD symptoms. In the 117 participants who were postmenopausal at the time of the questionnaire, 70% reported natural menopause (mean age: 48.9 years [SD 3.9]); fewer than 30% reported systemic hormone therapy (HT) use. Mean FS age was 40.1 years (SD 14.2). Ever-use of systemic hormonal contraceptives (HC) was marginally associated with earlier FS (39 vs 43 years, p = 0.05). Because HC use may decrease parity, when we included both variables in the model, the association between HC use and FS age became more significant (estimate = 2.7, p = 0.007). Among postmenopausal participants, 24% reported NMOSD onset within 2 years of (before or after) menopause. Among these participants, there was no association between age at menopause or HT use and age at NMOSD onset. Conclusions: Overall, age at NMOSD onset did not show a strong relationship with endogenous hormonal exposures. An earlier onset age did appear to be marginally associated with systemic HC exposure, an association that requires confirmation in future studies.

  • Publication

    An expanded composite scale of MRI-defined disease severity in multiple sclerosis: MRDSS2

    (Lippincott Williams & Wilkins, 2014) Bakshi, Rohit; Neema, M; Tauhid, Shahamat; Healy, Brian C.; Glanz, Bonnie; Kim, Gloria; Miller, Jennifer; Berkowitz, Julia L.; Bove, Riley; Houtchens, Maria; Severson, Christopher; Stankiewicz, James; Stazzone, Lynn; Chitnis, Tanuja; Guttmann, Charles R.G.; Weiner, Howard; Ceccarelli, Antonia

    The objective of this study was to test a new version of the Magnetic Resonance Disease Severity Scale (MRDSS2), incorporating cerebral gray matter (GM) and spinal cord involvement from 3 T MRI, in modeling the relationship between MRI and physical disability or cognitive status in multiple sclerosis (MS). Fifty-five MS patients and 30 normal controls underwent high-resolution 3 T MRI. The patients had an Expanded Disability Status Scale score of 1.6±1.7 (mean±SD). The cerebral normalized GM fraction (GMF), the T2 lesion volume (T2LV), and the ratio of T1 hypointense LV to T2LV (T1/T2) were derived from brain images. Upper cervical spinal cord area (UCCA) was obtained from spinal cord images. A within-subject d-score (difference of MS from normal control) for each MRI component was calculated, equally weighted, and summed to form MRDSS2. With regard to the relationship between physical disability and MRDSS2 or its individual components, MRI–Expanded Disability Status Scale correlations were significant for MRDSS2 (r=0.33, P=0.013) and UCCA (r=−0.33, P=0.015), but not for GMF (P=0.198), T2LV (P=0.707), and T1/T2 (P=0.240). The inclusion of UCCA appeared to drive this MRI–disability relationship in MRDSS2. With regard to cognition, MRDSS2 showed a larger effect size (P=0.035) than its individual components [GMF (P=0.081), T2LV (P=0. 179), T1/T2 (P=0.043), and UCCA (P=0.818)] in comparing cognitively impaired with cognitively preserved patients (defined by the Minimal Assessment of Cognitive Function in MS). Both cerebral lesions (T1/T2) and atrophy (GMF) appeared to drive this relationship. We describe a new version of the MRDSS, which has been expanded to include cerebral GM and spinal cord involvement. MRDSS2 has concurrent validity with clinical status.

  • Publication

    Handling changes in MRI acquisition parameters in modeling whole brain lesion volume and atrophy data in multiple sclerosis subjects: Comparison of linear mixed-effect models

    (Elsevier, 2015) Chua, Alicia S.; Egorova, Svetlana; Anderson, Mark C.; Polgar-Turcsanyi, Mariann; Chitnis, Tanuja; Weiner, Howard; Guttmann, Charles R.G.; Bakshi, Rohit; Healy, Brian

    Magnetic resonance imaging (MRI) of the brain provides important outcome measures in the longitudinal evaluation of disease activity and progression in MS subjects. Two common measures derived from brain MRI scans are the brain parenchymal fraction (BPF) and T2 hyperintense lesion volume (T2LV), and these measures are routinely assessed longitudinally in clinical trials and observational studies. When measuring each outcome longitudinally, observed changes may be potentially confounded by variability in MRI acquisition parameters between scans. In order to accurately model longitudinal change, the acquisition parameters should thus be considered in statistical models. In this paper, several models for including protocol as well as individual MRI acquisition parameters in linear mixed models were compared using a large dataset of 3453 longitudinal MRI scans from 1341 subjects enrolled in the CLIMB study, and model fit indices were compared across the models. The model that best explained the variance in BPF data was a random intercept and random slope with protocol specific residual variance along with the following fixed-effects: baseline age, baseline disease duration, protocol and study time. The model that best explained the variance in T2LV was a random intercept and random slope along with the following fixed-effects: baseline age, baseline disease duration, protocol and study time. In light of these findings, future studies pertaining to BPF and T2LV outcomes should carefully account for the protocol factors within longitudinal models to ensure that the disease trajectory of MS subjects can be assessed more accurately.

  • Publication

    No sex-specific difference in disease trajectory in multiple sclerosis patients before and after age 50

    (BioMed Central, 2013) Bove, Riley; Musallam, Alexander; Healy, Brian; Houtchens, Maria; Glanz, Bonnie I; Khoury, Samia; Guttmann, Charles; De Jager, Philip; Chitnis, Tanuja

    Background: The disease course in multiple sclerosis (MS) is influenced by many factors, including age, sex, and sex hormones. Little is known about sex-specific changes in disease course around age 50, which may represent a key biological transition period for reproductive aging. Methods: Male and female subjects with no prior chemotherapy exposure were selected from a prospective MS cohort to form groups representing the years before (38–46 years, N=351) and after (54–62 years, N=200)age 50. Primary analysis assessed for interaction between effects of sex and age on clinical (Expanded Disability Status Scale, EDSS; relapse rate) and radiologic (T2 lesion volume, T2LV; brain parenchymal fraction, BPF) outcomes. Secondarily, we explored patient-reported outcomes (PROs). Results: As expected, there were age- and sex- related changes with male and older cohorts showing worse disease severity (EDSS), brain atrophy (BPF), and more progressive course. There was no interaction between age and sex on cross-sectional adjusted clinical (EDSS, relapse rate) or radiologic (BPF, T2LV) measures, or on 2-year trajectories of decline. There was a significant interaction between age and sex for a physical functioning PRO (SF-36): the older female cohort reported lower physical functioning than men (p=0.002). There were no differences in depression (Center for Epidemiological Study – Depression, CES-D) or fatigue (Modified Fatigue Impact Scale, MFIS) scores. Conclusions: There was no interaction between age and sex suggestive of an effect of reproductive aging on clinical or radiologic progression. Prospective analyses across the menopausal transition are needed.

  • Publication

    Brain MRI lesions and atrophy are associated with employment status in patients with multiple sclerosis

    (Springer Berlin Heidelberg, 2015) Tauhid, Shahamat; Chu, Renxin; Sasane, Rahul; Glanz, Bonnie; Neema, Mohit; Miller, Jennifer R.; Kim, Gloria; Signorovitch, James E.; Healy, Brian; Chitnis, Tanuja; Weiner, Howard; Bakshi, Rohit

    Multiple sclerosis (MS) commonly affects occupational function. We investigated the link between brain MRI and employment status. Patients with MS (n = 100) completed a Work Productivity and Activity Impairment (WPAI) (general health version) survey measuring employment status, absenteeism, presenteeism, and overall work and daily activity impairment. Patients “working for pay” were considered employed; “temporarily not working but looking for work,” “not working or looking for work due to age,” and “not working or looking for work due to disability” were considered not employed. Brain MRI T1 hypointense (T1LV) and T2 hyperintense (T2LV) lesion volumes were quantified. To assess lesional destructive capability, we calculated each subject’s ratio of T1LV to T2LV (T1/T2). Normalized brain parenchymal volume (BPV) assessed brain atrophy. The mean (SD) age was 45.5 (9.7) years; disease duration was 12.1 (8.1) years; 75 % were women, 76 % were relapsing-remitting, and 76 % were employed. T1LV, T1/T2, Expanded Disability Status Scale (EDSS) scores, and activity impairment were lower and BPV was higher in the employed vs. not employed group (Wilcoxon tests, p < 0.05). Age, disease duration, MS clinical subtype, and T2LV did not differ between groups (p > 0.05). In multivariable logistic regression modeling, adjusting for age, sex, and disease duration, higher T1LV predicted a lower chance of employment (p < 0.05). Pearson correlations showed that EDSS was associated with activity impairment (p < 0.05). Disease duration, age, and MRI measures were not correlated with activity impairment or other WPAI outcomes (p > 0.05). We report a link between brain atrophy and lesions, particularly lesions with destructive potential, to MS employment status.

  • Publication

    The Effect of Fingolimod on Conversion of Acute Gadolinium-Enhancing Lesions to Chronic T1 Hypointensities in Multiple Sclerosis

    (Wiley-Blackwell, 2015) Oommen Vinit, V; Tauhid, Shahamat; Healy Brian, C; Chua Alicia, S; Malik, MT; Diaz-Cruz, Camilo; Dupuy Sheena, L; Weiner Howard, L; Chitnis, Tanuja; Bakshi, Rohit

    BACKGROUND: Brain lesions converting to chronic T1 hypointensities (“chronic black holes” [CBH]), indicate severe tissue destruction (axonal loss and irreversible demyelination) in multiple sclerosis (MS). Two mechanisms by which fingolimod could limit MS lesion evolution include sequestration of lymphocytes in the periphery or direct neuroprotective effects. We investigated the effect of fingolimod on the evolution of acute gadolinium-enhancing (Gd+) brain lesions to CBH in patients with MS. METHODS: This was a retrospective nonrandomized comparison of patients with Gd+ brain lesions at the time of starting oral fingolimod [.5 mg/day, n = 26, age (mean ± SD) 39.2 ± 10.6 years, Expanded Disability Status Scale (EDSS) score - median (range): 1.75 (0, 6.5)] to those on no therapy [n = 30, age 41.7 ± 9.3 years; EDSS 1.0 (0, 6)]. Each lesion was classified by whether it converted to a CBH in the year following treatment. RESULTS: In the fingolimod group, 99 Gd+ baseline lesions (mean ± SD, range: 3.8 ± 5.1; 1, 21 per patient) were identified of which 25 (25%) evolved to CBH (1.0 ± 2.0; 0, 10 per patient). The untreated group had 62 baseline Gd + lesions (2.1 ± 2.3; 1, 13), 26 (42%) of which evolved to CBH (.9 ± 1.4; 0, 7) (P = .063). Thirteen patients (50%) receiving fingolimod and 17 untreated patients (57%) developed CBH (P = .79). CONCLUSION: This pilot study shows a trend of fingolimod on reducing the conversion rate from acute to chronic destructive MS lesions. Such an effect awaits verification in larger randomized prospective studies.