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Dive into the research topics where Apoorva K. Chandar is active.

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Featured researches published by Apoorva K. Chandar.


JAMA | 2016

Association of Pharmacological Treatments for Obesity With Weight Loss and Adverse Events: A Systematic Review and Meta-analysis

Rohan Khera; Mohammad Hassan Murad; Apoorva K. Chandar; Parambir S. Dulai; Zhen Wang; Larry J. Prokop; Rohit Loomba; Michael Camilleri; Siddharth Singh

IMPORTANCE Five medications have been approved for the management of obesity, but data on comparative effectiveness are limited. OBJECTIVE To compare weight loss and adverse events among drug treatments for obesity using a systematic review and network meta-analysis. DATA SOURCES MEDLINE, EMBASE, Web of Science, Scopus, and Cochrane Central from inception to March 23, 2016; clinical trial registries. STUDY SELECTION Randomized clinical trials conducted among overweight and obese adults treated with US Food and Drug Administration-approved long-term weight loss agents (orlistat, lorcaserin, naltrexone-bupropion, phentermine-topiramate, or liraglutide) for at least 1 year compared with another active agent or placebo. DATA EXTRACTION AND SYNTHESIS Two investigators identified studies and independently abstracted data using a predefined protocol. A Bayesian network meta-analysis was performed and relative ranking of agents was assessed using surface under the cumulative ranking (SUCRA) probabilities. Quality of evidence was assessed using GRADE criteria. MAIN OUTCOMES AND MEASURES Proportions of patients with at least 5% weight loss and at least 10% weight loss, magnitude of decrease in weight, and discontinuation of therapy because of adverse events at 1 year. RESULTS Twenty-eight randomized clinical trials with 29 018 patients (median age, 46 years; 74% women; median baseline body weight, 100.5 kg; median baseline body mass index, 36.1) were included. A median 23% of placebo participants had at least 5% weight loss vs 75% of participants taking phentermine-topiramate (odds ratio [OR], 9.22; 95% credible interval [CrI], 6.63-12.85; SUCRA, 0.95), 63% of participants taking liraglutide (OR, 5.54; 95% CrI, 4.16-7.78; SUCRA, 0.83), 55% taking naltrexone-bupropion (OR, 3.96; 95% CrI, 3.03-5.11; SUCRA, 0.60), 49% taking lorcaserin (OR, 3.10; 95% CrI, 2.38-4.05; SUCRA, 0.39), and 44% taking orlistat (OR, 2.70; 95% CrI, 2.34-3.09; SUCRA, 0.22). All active agents were associated with significant excess weight loss compared with placebo at 1 year-phentermine-topiramate, 8.8 kg (95% CrI, -10.20 to -7.42 kg); liraglutide, 5.3 kg (95% CrI, -6.06 to -4.52 kg); naltrexone-bupropion, 5.0 kg (95% CrI, -5.94 to -3.96 kg); lorcaserin, 3.2 kg (95% CrI, -3.97 to -2.46 kg); and orlistat, 2.6 kg (95% CrI, -3.04 to -2.16 kg). Compared with placebo, liraglutide (OR, 2.95; 95% CrI, 2.11-4.23) and naltrexone-bupropion (OR, 2.64; 95% CrI, 2.10-3.35) were associated with the highest odds of adverse event-related treatment discontinuation. High attrition rates (30%-45% in all trials) were associated with lower confidence in estimates. CONCLUSIONS AND RELEVANCE Among overweight or obese adults, orlistat, lorcaserin, naltrexone-bupropion, phentermine-topiramate, and liraglutide, compared with placebo, were each associated with achieving at least 5% weight loss at 52 weeks. Phentermine-topiramate and liraglutide were associated with the highest odds of achieving at least 5% weight loss.


Gastroenterology | 2015

Comparative Effectiveness of Pharmacological Interventions for Severe Alcoholic Hepatitis: A Systematic Review and Network Meta-analysis

Siddharth Singh; Mohammad Hassan Murad; Apoorva K. Chandar; Connie M. Bongiorno; Ashwani K. Singal; Stephen R. Atkinson; Mark Thursz; Rohit Loomba; Vijay H. Shah

BACKGROUND & AIMS Severe alcoholic hepatitis (AH) has high mortality. We assessed the comparative effectiveness of pharmacological interventions for severe AH, through a network meta-analysis combining direct and indirect treatment comparisons. METHODS We conducted a systematic literature review, through February 2015, for randomized controlled trials of adults with severe AH (discriminant function ≥32 and/or hepatic encephalopathy) that compared the efficacy of active pharmacologic interventions (corticosteroids, pentoxifylline, and N-acetylcysteine [NAC], alone or in combination) with each other or placebo, in reducing short-term mortality (primary outcome) and medium-term mortality, acute kidney injury, and/or infections (secondary outcomes). We performed direct and Bayesian network meta-analysis for all treatments, and used Grading of Recommendations Assessment, Development and Evaluation criteria to appraise quality of evidence. RESULTS We included 22 randomized controlled trials (2621 patients) comparing 5 different interventions. In a direct meta-analysis, only corticosteroids decreased risk of short-term mortality. In a network meta-analysis, moderate quality evidence supported the use of corticosteroids alone (relative risk [RR], 0.54; 95% credible interval [CrI], 0.39-0.73) or in combination with pentoxifylline (RR, 0.53; 95% CrI, 0.36-0.78) or NAC (RR, 0.15; 95% CI, 0.05-0.39), to reduce short-term mortality; low quality evidence showed that pentoxifylline also decreased short-term mortality (RR, 0.70; 95% CrI, 0.50-0.97). The addition of NAC, but not pentoxifylline, to corticosteroids may be superior to corticosteroids alone for reducing short-term mortality. No treatment was effective in reducing medium-term mortality. Imprecise estimates and the small number of direct trials lowered the confidence in several comparisons. CONCLUSIONS In patients with severe AH, pentoxifylline and corticosteroids (alone and in combination with pentoxifylline or NAC) can reduce short-term mortality. No treatment decreases risk of medium-term mortality.


Inflammatory Bowel Diseases | 2015

Association Between Inflammatory Bowel Disease and Vitamin D Deficiency: A Systematic Review and Meta-analysis.

Rita Del Pinto; D. Pietropaoli; Apoorva K. Chandar; Claudio Ferri; Fabio Cominelli

Background:Vitamin D plays a role in several immune-mediated diseases, but its association with inflammatory bowel disease (IBD) is unclear. We conducted a systematic review and meta-analysis to assess the association between IBD and vitamin D deficiency. Methods:We searched electronic databases from inception to December 2014 for observational studies reporting the presence of vitamin D deficiency (defined as serum 25-hydroxycholecalciferol [25(OH)D] level of ⩽20 ng/mL) in IBD patients and having a control group without IBD. Odds ratios (ORs) were combined using a random-effects model. Meta-regression was performed using latitude as a moderator. Study quality was assessed using the Newcastle–Ottawa scale. Results:Out of 816 citations, 14 eligible studies were identified, comprising 1891 participants (938 IBD cases and 953 controls). Meta-analysis showed that patients with IBD had 64% higher odds of vitamin D deficiency when compared with controls (OR = 1.64; 95% confidence interval, 1.30–2.08; I2 = 7%; P < 0.0001). Patients with ulcerative colitis had more than double the odds of vitamin D deficiency when compared with normal controls (OR = 2.28; 95% confidence interval, 1.18–4.41; I2 = 41%; P = 0.01). Latitude did not influence the association between IBD and vitamin D deficiency (P = 0.34). Generalizability of our results might be limited as we summarized unadjusted ORs, because of nonavailability of adjusted ORs in individual studies. Conclusions:IBD is significantly associated with having higher odds of vitamin D deficiency. Well-designed randomized controlled trials and longitudinal studies are needed to further explain the role of vitamin D in IBD pathogenesis and its therapy.


Inflammatory Bowel Diseases | 2014

Efficacy and Safety of Natalizumab and Vedolizumab for the Management of Crohn's Disease: A Systematic Review and Meta-analysis.

Apoorva K. Chandar; Siddharth Singh; Mohammad Hassan Murad; Laurent Peyrin-Biroulet; Edward V. Loftus

Background:We assessed the risk-benefit profile of anti-&agr;4-integrins, natalizumab (NAT), and vedolizumab (VEDO), in Crohns disease through a systematic review and meta-analysis of randomized controlled trials. Methods:We searched multiple electronic databases through July 2014 and identified 8 randomized controlled trials in adults with Crohns disease comparing NAT (5 trials) or VEDO (3 trials) with placebo. Efficacy outcomes were induction of remission, response, and improvement in quality of life; safety outcomes were serious adverse events, infusion reactions, infections, and treatment discontinuation. We performed subgroup analysis based on anti–tumor necrosis factor (TNF)-&agr; exposure and estimated summary relative risk (RR) or mean difference, with 95% confidence intervals (CIs). Results:Anti-&agr;4-integrins were superior to placebo for induction of remission (RR, 0.87; 95% CI, 0.84–0.91), with similar estimates for NAT (RR, 0.86; 95% CI, 0.80–0.93) and VEDO (RR, 0.87; 95% CI, 0.79–0.95). Both NAT and VEDO were equally efficacious for anti-TNF-naive (NAT: RR, 0.87; 95% CI, 0.75–1.00; VEDO: RR, 0.86; 95% CI, 0.79–0.94) and anti-TNF-exposed patients (NAT: RR, 0.86; 95% CI, 0.76–0.99; VEDO: RR, 0.89; 95% CI, 0.78–1.01). Anti-&agr;4-integrins were effective in inducing clinical response and improving quality of life, with no significant difference between NAT and VEDO. Rates of serious adverse events, infusion reactions, infections, and treatment discontinuation were similar for NAT and VEDO. No cases of progressive multifocal leukoencephalopathy have been observed with VEDO to date. Conclusions:NAT and VEDO are effective in inducing remission and response in patients with Crohns disease, with similar efficacy in anti-TNF-naive and anti-TNF-exposed patients.


Clinical Gastroenterology and Hepatology | 2015

Association of Serum Levels of Adipokines and Insulin With Risk of Barrett's Esophagus: A Systematic Review and Meta-Analysis

Apoorva K. Chandar; Swapna Devanna; Chang Lu; Siddharth Singh; Katarina B. Greer; Amitabh Chak; Prasad G. Iyer

BACKGROUND & AIMS Metabolically active visceral fat may be associated with esophageal inflammation, metaplasia, and neoplasia. We performed a meta-analysis to evaluate the association of serum adipokines and insulin with Barretts esophagus (BE). METHODS We performed a systematic search of multiple electronic databases, through April 2015, to identify all studies reporting associations between leptin, adiponectin, insulin, insulin resistance, and risk of BE in adults. Comparing the highest study-specific category with the reference category for each hormone, we estimated the summary adjusted odds ratio (aOR) and 95% confidence intervals (CI), using a random effects model. RESULTS We identified 9 observational studies (10 independent cohorts; 1432 patients with BE total, and 3550 control subjects). Meta-analysis revealed that high serum level of leptin was associated with 2-fold higher risk of BE (BE cases vs population control subjects in 5 studies: aOR, 2.23; 95% CI, 1.31-3.78; I(2), 59%). Total serum level of adiponectin was not associated with BE (BE cases vs population control subjects in 5 studies: aOR, 0.79; 95% CI, 0.46-1.34; I(2), 65%), although 1 study observed decreased risk of BE with increased level of low-molecular-weight adiponectin. High serum level of insulin was associated with increased risk of BE (BE cases vs population control subjects in 3 studies: aOR, 1.74; 95% CI, 1.14-2.65; I(2), 0), whereas insulin resistance was not associated with increased risk of BE (BE cases vs gastroesophageal reflux disease control subjects in 2 studies: aOR, 0.98; 95% CI, 0.42-2.30; I(2), 64%). CONCLUSIONS Increased serum levels of leptin and insulin are associated with increased risk of BE, compared with population control subjects. In contrast, increased total serum levels of adiponectin and insulin do not seem to modify BE risk. Well-designed longitudinal studies of incident BE are needed to clarify existing associations of serum adipokines and insulin with BE.


The Lancet Gastroenterology & Hepatology | 2017

Comparative efficacy of pharmacological strategies for management of type 1 hepatorenal syndrome: a systematic review and network meta-analysis

Antonio Facciorusso; Apoorva K. Chandar; M. Hassan Murad; Larry J. Prokop; Nicola Muscatiello; Patrick S. Kamath; Siddharth Singh

BACKGROUND Several drugs have been studied to improve outcomes for patients with hepatorenal syndrome, but trials have reported variable efficacy. We aimed to compare the efficacy of different management strategies for type 1 hepatorenal syndrome. METHODS For this systematic review and network meta-analysis, we searched Ovid MEDLINE In-Process & Other Non-Indexed Citations, Ovid MEDLINE, Ovid Embase, Ovid Cochrane Central Register of Controlled Trials, Scopus, and Web of Science for papers published up to June 9, 2016. We selected randomised controlled trials of adults (>18 years) with decompensated cirrhosis and type 1 hepatorenal syndrome that compared the efficacy of active vasoactive drugs (terlipressin, midodrine, octreotide, noradrenaline, and dopamine; alone or in combination) with placebo or each other. The primary outcome was reduction in short-term mortality. Secondary outcomes were reversal of hepatorenal syndrome, relapse of hepatorenal syndrome after initial reversal, and adverse events. We did pairwise and network meta-analyses to produce odds ratios (ORs) and 95% CIs. We used the GRADE criteria to appraise quality of evidence. FINDINGS We identified 13 randomised controlled trials done in 739 adults with type 1 hepatorenal syndrome. All participants received supportive therapy with albumin. Moderate-quality evidence might support the use of terlipressin over placebo for reduction of short-term mortality (OR 0·65, 95% CI 0·41-1·05), whereas only low-quality evidence supported the use of noradrenaline, midodrine plus octreotide, and dopamine plus furosemide over placebo to reduce mortality, and no ORs for any of the comparisons versus placebo were significant. Moderate-quality evidence supported the use of terlipressin over midodrine plus octreotide (OR 26·25, 95% CI 3·07-224·21) to reverse hepatorenal syndrome, with low-quality evidence supporting the use of noradrenaline over placebo (4·17, 1·37-12·50) and over midodrine plus octreotide (10·00, 1·49-50·00) for this outcome. A median of 16% (range 5-20) of terlipressin-treated patients, and 33% (range 6-40) noradrenaline-treated patients with reversal of hepatorenal syndrome had recurrence on discontinuation of therapy. A median of 8% (range 4-22) terlipressin-treated patients required discontinuation of therapy due to serious adverse events. INTERPRETATION Terlipressin with albumin might reduce short-term mortality compared with placebo in patients with type 1 hepatorenal syndrome. Terlipressin with albumin and noradrenaline with albumin are both superior to midodrine plus octreotide with albumin for reversal of hepatorenal syndrome. Pragmatic clinical trials of terlipressin with albumin are warranted to evaluate real-world effectiveness and safety in patients with type 1 hepatorenal syndrome. FUNDING None.


Cancer Research | 2016

RNA sequencing identifies transcriptionally viable gene fusions in esophageal adenocarcinomas

Andrew Blum; Srividya Venkitachalam; Yan Guo; Ann Marie Kieber-Emmons; Lakshmeswari Ravi; Apoorva K. Chandar; Prasad G. Iyer; Marcia I. Canto; Jean S. Wang; Nicholas J. Shaheen; Jill S. Barnholtz-Sloan; Sanford D. Markowitz; Joseph Willis; Yu Shyr; Amitabh Chak; Vinay Varadan; Kishore Guda

Esophageal adenocarcinoma is a deadly cancer with increasing incidence in the United States, but mechanisms underlying pathogenesis are still mostly elusive. In addressing this question, we assessed gene fusion landscapes by comprehensive RNA sequencing (RNAseq) of 55 pretreatment esophageal adenocarcinoma and 49 nonmalignant biopsy tissues from patients undergoing endoscopy for Barretts esophagus. In this cohort, we identified 21 novel candidate esophageal adenocarcinoma-associated fusions occurring in 3.33% to 11.67% of esophageal adenocarcinomas. Two candidate fusions were selected for validation by PCR and Sanger sequencing in an independent set of pretreatment esophageal adenocarcinoma (N = 115) and nonmalignant (N = 183) biopsy tissues. In particular, we observed RPS6KB1-VMP1 gene fusion as a recurrent event occurring in approximately 10% of esophageal adenocarcinoma cases. Notably, esophageal adenocarcinoma cases harboring RPS6KB1-VMP1 fusions exhibited significantly poorer overall survival as compared with fusion-negative cases. Mechanistic investigations established that the RPS6KB1-VMP1 transcript coded for a fusion protein, which significantly enhanced the growth rate of nondysplastic Barretts esophagus cells. Compared with the wild-type VMP1 protein, which mediates normal cellular autophagy, RPS6KB1-VMP1 fusion exhibited aberrant subcellular localization and was relatively ineffective in triggering autophagy. Overall, our findings identified RPS6KB1-VMP1 as a genetic fusion that promotes esophageal adenocarcinoma by modulating autophagy-related processes, offering new insights into the molecular pathogenesis of esophageal adenocarcinomas. Cancer Res; 76(19); 5628-33. ©2016 AACR.


Gastrointestinal Endoscopy | 2014

Comparative acceptability of transnasal esophagoscopy and esophageal capsule esophagoscopy: a randomized, controlled trial in veterans

Amitabh Chak; Bronia Alashkar; Gerard Isenberg; Apoorva K. Chandar; Katarina B. Greer; Ashley Hepner; Richard Pulice; Srikrishna Vemana; Yngve Falck-Ytter; Ashley L. Faulx

BACKGROUND EGD screening for Barretts esophagus (BE) is costly, with insufficient evidence to support its effectiveness. OBJECTIVE To compare acceptance and tolerability of 2 novel, office-based, endoscopic screening techniques done on nonsedated patients. DESIGN Randomized block study design with allocation concealment. SETTING Outpatient clinic setting at a Veterans Affairs medical center. PATIENTS A total of 184 veterans with or without GERD symptoms. INTERVENTIONS Transnasal esophagoscopy (TNE) or esophageal capsule esophagoscopy (ECE). MAIN OUTCOME MEASUREMENTS Acceptance and tolerability of TNE and ECE and effectiveness of BE screening. RESULTS Esophageal screening was accepted by 184 of 1210 (15.2%) veterans. The majority were men (96%) and African American (58%), with a mean (± standard deviation) age of 58.9 (± 8.1) years. Five TNE participants (5%) and 2 ECE participants (2%) refused the assigned procedure after randomization (P = .25). Eleven patients (12.6%) randomized to TNE crossed the minimal clinically important threshold for overall procedure tolerability, as opposed to no patients randomized to ECE (P = .001). Effectiveness of BE screening was not significantly different in both procedures (TNE vs ECE = 3.2% vs 5.4%; P = .47). Overall, BE was present in 8 of 75 white participants (10.6%) and in 0 of 107 African American participants (P < .001). LIMITATIONS The general veteran population may not reflect the screening population for BE. CONCLUSION Despite a small proportion of veterans expressing interest in esophageal screening, both TNE and ECE were feasible in the outpatient clinic setting and were accepted by >95% of participants who did express an interest. Screening was effective only in white participants. Moderate differences in tolerability between TNE and ECE notwithstanding, cost considerations along with availability of equipment and trained personnel should guide the modality to be used for BE screening.


Gastroenterology Clinics of North America | 2015

Role of Obesity in the Pathogenesis and Progression of Barrett’s Esophagus

Apoorva K. Chandar; Prasad G. Iyer

Central obesity is involved in the pathogenesis and progression of Barretts esophagus to esophageal adenocarcinoma. Involved are likely both mechanical and nonmechanical effects. Mechanical effects of increased abdominal fat cause disruption of the gastroesophageal reflux barrier leading to increased reflux events. Nonmechanical effects may be mediated by inflammation, via classically activated macrophages, pro-inflammatory cytokines, and adipokines such as Leptin, all of which likely potentiate reflux-mediated inflammation. Insulin resistance, associated with central obesity, is also associated with both Barretts pathogenesis and progression to adenocarcinoma. Molecular pathways activated in obesity, inflammation and insulin resistance overlap with those involved in Barretts pathogenesis and progression.


Science Translational Medicine | 2018

Identifying DNA methylation biomarkers for non-endoscopic detection of Barrett’s esophagus

Helen Moinova; Thomas LaFramboise; James Lutterbaugh; Apoorva K. Chandar; John A. Dumot; Ashley L. Faulx; Wendy Brock; Omar De La Cruz Cabrera; Kishore Guda; Jill S. Barnholtz-Sloan; Prasad G. Iyer; Marcia I. Canto; Jean S. Wang; Nicholas J. Shaheen; Prashanti Thota; Joseph Willis; Amitabh Chak; Sanford D. Markowitz

Combining DNA methylation markers with a swallowable device for sampling the distal esophagus effectively detects Barrett’s neoplasias. A test that goes down easy Barrett’s esophagus is a premalignant condition of the distal esophagus that increases the risk of esophageal cancer. Unfortunately, screening for Barrett’s esophagus currently requires endoscopy, an invasive and expensive procedure, and thus, it is not routinely performed. Moinova et al. have now demonstrated a simplified approach to screening by identifying a pair of DNA methylation markers that correlate with the presence of Barrett’s esophagus. The authors also invented a swallowable balloon-based device that can capture DNA samples for methylation analysis and found that it is well tolerated in patients and provides >90% sensitivity and specificity compared to endoscopy, suggesting its potential as a screening method. We report a biomarker-based non-endoscopic method for detecting Barrett’s esophagus (BE) based on detecting methylated DNAs retrieved via a swallowable balloon-based esophageal sampling device. BE is the precursor of, and a major recognized risk factor for, developing esophageal adenocarcinoma. Endoscopy, the current standard for BE detection, is not cost-effective for population screening. We performed genome-wide screening to ascertain regions targeted for recurrent aberrant cytosine methylation in BE, identifying high-frequency methylation within the CCNA1 locus. We tested CCNA1 DNA methylation as a BE biomarker in cytology brushings of the distal esophagus from 173 individuals with or without BE. CCNA1 DNA methylation demonstrated an area under the curve of 0.95 for discriminating BE-related metaplasia and neoplasia cases versus normal individuals, performing identically to methylation of VIM DNA, an established BE biomarker. When combined, the resulting two biomarker panel was 95% sensitive and 91% specific. These results were replicated in an independent validation cohort of 149 individuals who were assayed using the same cutoff values for test positivity established in the training population. To progress toward non-endoscopic esophageal screening, we engineered a well-tolerated, swallowable, encapsulated balloon device able to selectively sample the distal esophagus within 5 min. In balloon samples from 86 individuals, tests of CCNA1 plus VIM DNA methylation detected BE metaplasia with 90.3% sensitivity and 91.7% specificity. Combining the balloon sampling device with molecular assays of CCNA1 plus VIM DNA methylation enables an efficient, well-tolerated, sensitive, and specific method of screening at-risk populations for BE.

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Amitabh Chak

Case Western Reserve University

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Nicholas J. Shaheen

University of North Carolina at Chapel Hill

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Joseph Willis

Case Western Reserve University

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Sanford D. Markowitz

Case Western Reserve University

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Kishore Guda

Case Western Reserve University

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Andrew Blum

Case Western Reserve University

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Jill S. Barnholtz-Sloan

Case Western Reserve University

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