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Younossi, Zobair M.

https://orcid.org/0000-0001-9313-577X

Mayo Clinic

Inova Health System

Citations 13

Reliability of histologic assessment for NAFLD and development of an expanded NAFLD activity score
Pai, Rish K. , Hogan, Malcolm , Zou, Guangyong , Adeyi, Oyedele , Anstee, Quentin M. , Aqel, Bashar , Behling, Cynthia , Carey, Elizabeth J. , Feagan, Brian G. , McFarlane, Stefanie C., Noureddin, Mazen , Younossi, Zobair M. , Loomba, Rohit , Ratziu, Vlad , Anstee, Quentin M , Corey, Kathleen , Ma, C , Ratziu, Vlad , Loomba, Rohit , Ratziu, Vlad , Adeyi, Oyedele , Zou, Guangyong , Jairath, Vipul , Aqel, Bashar A. , Clouston, Andrew Donald , Corey, Kathleen E. , Kleiner, David Erwin , Ma, Christopher , Valasek, Mark A. , Harrison, Stephen A.

Hepatology | March 25, 2022 | Volume: 76 | Issue: 4 | Pages: 1150-1163

10.1002/hep.32475 Get It

Abstract Background and Aims The NASH Clinical Research Network histologic scoring system, the gold‐standard NASH histology assessment for clinical trials, has demonstrated intrarater and interrater variability. An expert panel in a previous systematic Research and Development/University of California Los Angeles (RAND/UCLA) study determined that existing histologic scoring systems do not fully capture NASH disease activity and fibrosis, and standardized definitions of histologic features are needed. We evaluated the reliability of existing and alternate histologic measures and their correlations with a disease activity visual analog scale to propose optimal components for an expanded NAFLD activity score (NAS). Approach and Results Four liver pathologists who were involved in the prior RAND/UCLA study underwent standardized training and multiple discussions with the goal of improving agreement. They were blinded to clinical information and scored histologic measures twice, ≥2 weeks apart, for 40 liver biopsies representing the full spectrum of NAFLD. Index intraclass correlation coefficient (ICC) estimates demonstrated intrarater (0.80–0.85) and interrater (0.60–0.72) reliability. Hepatocyte ballooning items had similar interrater ICCs (0.68–0.79), including those extending scores from 0–2 to 0–4. Steatosis measures (interrater ICCs, 0.72–0.80) correlated poorly with disease activity. Correlations with disease activity were largest for hepatocyte ballooning and Mallory‐Denk bodies (MDBs), with both used to develop the expanded NAS (intrarater ICC, 0.90; interrater ICC, 0.80). Fibrosis measures had ICCs of 0.70–0.87. Conclusions After extensive preparation among a group of experienced pathologists, we demonstrated improved reliability of multiple existing histologic NAFLD indices and fibrosis staging systems. Hepatocyte ballooning and MDBs most strongly correlated with disease activity and were used for the expanded NAS. Further validation including evaluation of responsiveness is required.
Increased risk of mortality by fibrosis stage in nonalcoholic fatty liver disease: Systematic review and meta‐analysis
Dulai, Parambir S. , Singh, Siddharth , Patel, Janki , Soni, Meera, Younossi, Zobair M. , Sebastiani, Giada , Ekstedt, Mattias , Hagström, Hannes , Stål, Per , Hultcrantz, Rolf, Loomba, Rohit , Prokop, Larry J. , Nasr, Patrik , Wong, Vincent Wai‐Sun , Kechagias, Stergios , Loomba, Rohit , Hagström, Hannes , Stål, Per

Hepatology | January 28, 2017 | Volume: 65 | Issue: 5 | Pages: 1557-1565

10.1002/hep.29085 Get It

Liver fibrosis is the most important predictor of mortality in nonalcoholic fatty liver disease (NAFLD). Quantitative risk of mortality by fibrosis stage has not been systematically evaluated. We aimed to quantify the fibrosis stage–specific risk of all‐cause and liver‐related mortality in NAFLD. Through a systematic review and meta‐analysis, we identified five adult NAFLD cohort studies reporting fibrosis stage–specific mortality (0‐4). Using fibrosis stage 0 as a reference population, fibrosis stage–specific mortality rate ratios (MRRs) with 95% confidence intervals (CIs) for all‐cause and liver‐related mortality were estimated. The study is reported according to the Preferred Reporting Items for Systematic Reviews and Meta‐Analyses statement. Included were 1,495 NAFLD patients with 17,452 patient years of follow‐up. Compared to NAFLD patients with no fibrosis (stage 0), NAFLD patients with fibrosis were at an increased risk for all‐cause mortality, and this risk increased with increases in the stage of fibrosis: stage 1, MRR = 1.58 (95% CI 1.19‐2.11); stage 2, MRR = 2.52 (95% CI 1.85‐3.42); stage 3, MRR = 3.48 (95% CI 2.51‐4.83); and stage 4, MRR = 6.40 (95% CI 4.11‐9.95). The results were more pronounced as the risk of liver‐related mortality increased exponentially with each increase in the stage of fibrosis: stage 1, MRR = 1.41 (95% CI 0.17‐11.95); stage 2, MRR = 9.57 (95% CI 1.67‐54.93); stage 3, MRR = 16.69 (95% CI 2.92‐95.36); and stage 4, MRR = 42.30 (95% CI 3.51‐510.34). Limitations of the study include an inability to adjust for comorbid conditions or demographics known to impact fibrosis progression in NAFLD and the inclusion of patients with simple steatosis and nonalcoholic steatohepatitis without fibrosis in the reference comparison group. Conclusion: The risk of liver‐related mortality increases exponentially with increase in fibrosis stage; these data have important implications in assessing the utility of each stage and benefits of regression of fibrosis from one stage to another. (H epatology 2017;65:1557‐1565).
The impact of hepatitis C burden: an evidence‐based approach
Younossi, Zobair M. , Kanwal, Fasiha , Saab, Sammy , Brown, Kimberly , El‐Serag, Hashem B. , Kim, W. Ray , Kugelmas, Marcelo , Kanwal, Fasiha , Ahmed, Aijaz , Gordon, Stuart C.

Alimentary Pharmacology & Therapeutics | January 27, 2014 | Volume: 39 | Issue: 5 | Pages: 518-531

10.1111/apt.12625 Get It

SummaryBackgroundInfection with the hepatitis C virus (HCV) has been considered a major cause of mortality, morbidity and resource utilisation in the US. In addition, HCV is the main cause of hepatocellular cancer (HCC) in the US. Recent developments in the diagnosis and treatment of HCV, including new recommendations pertaining to screening for HCV by the Centers for Disease Control and Prevention and newer treatment regimens with high efficacy, short duration and the potential for interferon‐free therapies, have energised the health care practitioners regarding HCV management.AimTo assess the full impact of HCV burden on clinical, economic and patient‐reported outcomes.MethodsAn expert panel was convened to assess the full impact of HCV burden on a number of important outcomes using an evidence‐based approach predicated on Grading of Recommendations Assessment, Development and Evaluation methodology. The literature was summarised, graded using an evidence‐based approach and presented during the workshop. Workshop presentations were intended to review recent, relevant evidence‐based literature and provide graded summary statements pertaining to HCV burden on topics including the relationships between HCV and the development of important outcomes.ResultsThe associations of HCV with cirrhosis, HCC, liver‐related mortality, type 2 diabetes mellitus, rheumatological diseases and quality of life impairments are supported by strong evidence. Also, there is strong evidence that sustained viral eradication of HCV can improve important outcomes such as mortality and quality of life.ConclusionsThe current evidence suggests that HCV has been associated with tremendous clinical, economic and quality of life burden.