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- Dulai, Parambir S, et al.
(författare)
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Increased risk of mortality by fibrosis stage in non-alcoholic fatty liver disease : Systematic Review and Meta-analysis.
- 2017
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Ingår i: Hepatology. - : John Wiley & Sons. - 0270-9139 .- 1527-3350. ; 65:5, s. 1557-1565
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Forskningsöversikt (refereegranskat)abstract
- BACKGROUND: 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.METHODS: Through a systematic review and meta-analysis, we identified 5 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 (MRR) with 95% confidence intervals (CI), for all-cause and liver-related mortality, were estimated. The study is reported according to the PRISMA statement.RESULTS: 1,495 NAFLD patients with 17,452 patient years of follow-up were included. 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 increase 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 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: Inability to adjust for co-morbid conditions or demographics known to impact fibrosis progression in NAFLD, and the inclusion of patients with simple steatosis and NASH 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 utility of each stage and benefits of regression of fibrosis from one stage to another. This article is protected by copyright. All rights reserved.
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| 2. |
- Middleton, Michael, et al.
(författare)
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Quantifying Abdominal Adipose Tissue and Thigh Muscle Volume and Hepatic Proton Density Fat Fraction : Repeatability and Accuracy of an MR Imaging–based, Semiautomated Analysis Method
- 2017
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Ingår i: Radiology. - : Radiological Society of North America, Inc.. - 0033-8419 .- 1527-1315. ; 283:2, s. 438-449
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Tidskriftsartikel (refereegranskat)abstract
- PurposeThe purpose of this study was to determine the repeatability and accuracy of an commercially available (Advanced MR Analytics [AMRA®]; Linköping, Sweden) magnetic resonance imaging (MRI)-based, semi-automated method to quantify abdominal adipose tissue and thigh muscle volume as well as hepatic proton density fat fraction (PDFF)Materials and MethodsThis prospective study was approved by an institutional review board (IRB) and was Health Insurance Portability and Accountability Act (HIPAA) compliant. All subjects provided written informed consent. Inclusion criteria were age ≥ 18 years, and willingness to participate. Exclusion criteria were contraindication to MRI. Three-dimensional, T1-weighted, dual-echo body-coil images were acquired from base of skull to knees at 3T, twice before and once after taking subjects off the scanner table (total of three acquisitions). Source images were reconstructed offline to generate water, and calibrated fat images where pure adipose tissue has unit value and absence of adipose tissue has zero value. Abdominal adipose tissues and thigh muscles were segmented, and their volumes estimated using AMRA a semi-automated analysis method and, as a reference standard, manually. Hepatic PDFF was estimated using a confounder-corrected chemical-shift encoded MRI method with hybrid complex-magnitude reconstruction., and, as a reference standard, with magnetic resonance spectroscopy (MRS). Tissue volume and hepatic PDFF intra- and inter-examination repeatability was assessed by intraclass correlation (ICC) and coefficient of variation (CV) analysis. Tissue volume and hepatic PDFF accuracies were assessed by linear regression using their respective reference standards.ResultsTwenty adult subjects were enrolled (18 female, age range 25 - 76 yrs, body mass index range 19.3 to 43.9 kg/m2). Adipose and thigh muscle tissue volumes estimated using the semi-automated analysis method had intra-and inter-examination ICCs between 0.996 and 0.998, and CVs between 1.5 and 3.6%. For hepatic MRI PDFF, intra- and inter-examination ICCs were ≥ 0.994 and CVs, ≤ 7.3%. Agreement between semi-automated and manual volume estimates, and between MRI and MRS hepatic PDFF estimates, was high, with regression slopes and intercepts not significantly different from the identity line (all p’s > 0.05), and R2’s between 0.744 and 0.994.ConclusionsThis MRI-based, semi-automated method provides high repeatability, and high accuracy for estimating abdominal adipose tissue and thigh muscle volumes, and hepatic PDFF.
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