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Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/87032/1/24410_ftp.pd

Genetic Admixture and Gallbladder Disease in Mexican Americans

Gallbladder disease is a common source of morbidity in the Mexican American population. Genetic heritage has been proposed as a possible contributor, but evidence for this is limited. Because gallbladder disease has been associated with Native American heritage, genetic admixture may serve as a useful proxy for genetic susceptibility to the disease in epidemiologic studies. The objective of our study was to examine thepossibility that gallbladder disease is associated with greater Native American admixture in Mexican Americans. This study used data from the Hispanic Health and Nutrition Examination Survey and was based on 1,145 Mexican Americans who underwent gallbladder ultrasonography and provided usable phenotypic information. We used the GM and KM immunoglobulin antigen system to generate estimates of admixture proportions and compared these for individuals with and without gallbladder disease. Overall, the proportionate genetic contributions from European, Native American, and African ancestries in our sample were 0.575, 0.390, and 0.035, respectively. Admixture proportions did not differ between cases and noncases: Estimates of Native American admixture for the two groups were 0.359 and 0.396, respectively, but confidence intervals for estimates overlapped. This study found no evidence for the hypothesis that greater Native American admixture proportion is associated with higher prevalence of gallbladder disease in Mexican Americans. Reasons for the finding that Native American admixture proportions did not differ between cases and noncases are discussed. Improving our understanding of the measurement, use, and limitations of genetic admixture may increase its usefulness as an epidemiologic tool as well as its potential for contributing to our understanding of disease distributions across populations

Liver regeneration after living donor transplantation: Adult‐to‐adult living donor liver transplantation cohort study

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Recipient Morbidity After Living and Deceased Donor Liver Transplantation: Findings from the A2ALL Retrospective Cohort Study †

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Laboratory test results after living liver donation in the adult-to-adult living donor liver transplantation cohort study

Information on the long-term health of living liver donors is incomplete. Because changes in standard laboratory tests may reflect the underlying health of donors, results before and after donation were examined in the Adult-to-Adult Living Donor Liver Transplantation Cohort Study (A2ALL). A2ALL followed 487 living liver donors who donated at 9 US transplant centers between 1998 and 2009. The aminotransferase [aspartate aminotransferase (AST) and alanine aminotransferase (ALT)] and alkaline phosphatase (AP) activities, bilirubin, international normalized ratio (INR), albumin, white blood cell count (WBC), hemoglobin (HGB), platelet count, ferritin, serum creatinine (SCR), and blood urea nitrogen (BUN) were measured at the evaluation and after donation (1 week, 1 month, 3 months, 1 year, and yearly thereafter). Repeated measures models were used to estimate median laboratory values at each time point and to test for differences between values at the evaluation (baseline) and postdonation time points. Platelet counts were significantly decreased at every time point in comparison with the baseline, and at 3 years, they were 19% lower. Approximately 10% of donors had a platelet count < 150 × 1000/mm 3 2 to 3 years post-donation. Donors with a platelet count ≤ 150 × 1000/mm 3 at 1 year had significantly lower mean platelet counts (189 ± 32 × 1000/mm 3 ) versus the remainder of the cohort (267 ± 56 × 1000/mm 3 , P < 0.0001) at the evaluation. Statistically significant differences compared to the evaluation values were noted for AST, AP, INR, and albumin through the first year, although most measurements were in the normal range. The median values for WBC, HGB, ferritin, albumin, SCR, BUN, and INR were not substantially outside the normal range at any time point. In conclusion, after 3 months, most laboratory values return to normal among right hepatic lobe liver donors, with a slower return to baseline levels for AST, AP, INR, and albumin. Persistently decreased platelet counts warrant further investigation. Liver Transpl, 2011. © 2011 AASLD.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/83476/1/22246_ftp.pd

Liver transplant recipient survival benefit with living donation in the model for endstage liver disease allocation era

Receipt of a living donor liver transplant (LDLT) has been associated with improved survival compared with waiting for a deceased donor liver transplant (DDLT). However, the survival benefit of liver transplant has been questioned for candidates with Model for Endstage Liver Disease (MELD) scores <15, and the survival advantage of LDLT has not been demonstrated during the MELD allocation era, especially for low MELD patients. Transplant candidates enrolled in the Adult‐to‐Adult Living Donor Liver Transplantation Cohort Study after February 28, 2002 were followed for a median of 4.6 years. Starting at the time of presentation of the first potential living donor, mortality for LDLT recipients was compared to mortality for patients who remained on the waiting list or received DDLT (no LDLT group) according to categories of MELD score (<15 or ≥15) and diagnosis of hepatocellular carcinoma (HCC). Of 868 potential LDLT recipients (453 with MELD <15; 415 with MELD ≥15 at entry), 712 underwent transplantation (406 LDLT; 306 DDLT), 83 died without transplant, and 73 were alive without transplant at last follow‐up. Overall, LDLT recipients had 56% lower mortality (hazard ratio [HR] = 0.44, 95% confidence interval [CI] 0.32‐0.60; P < 0.0001). Among candidates without HCC, mortality benefit was seen both with MELD <15 (HR = 0.39; P = 0.0003) and MELD ≥15 (HR = 0.42; P = 0.0006). Among candidates with HCC, a benefit of LDLT was not seen for MELD <15 (HR = 0.82, P = 0.65) but was seen for MELD ≥15 (HR = 0.29, P = 0.043). Conclusion: Across the range of MELD scores, patients without HCC derived a significant survival benefit when undergoing LDLT rather than waiting for DDLT in the MELD liver allocation era. Low MELD candidates with HCC may not benefit from LDLT. (H EPATOLOGY 2011;54:1313–1321)Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/86878/1/24494_ftp.pd

Prognostic value of Ishak fibrosis stage: Findings from the hepatitis C antiviral long-term treatment against cirrhosis trial

Studies of the prognostic value of Ishak fibrosis stage are lacking. We used multi-year follow-up of the Hepatitis C Antiviral Long-Term Treatment Against Cirrhosis (HALT-C) Trial to determine whether individual Ishak fibrosis stages predicted clinical outcomes in patients with chronic hepatitis C. Baseline liver biopsy specimens from 1050 patients with compensated chronic hepatitis C who had failed combination peginterferon and ribavirin were reviewed by a panel of expert hepatopathologists. Fibrosis was staged with the Ishak scale (ranging from 0 = no fibrosis to 6 = cirrhosis). Biopsy fragmentation and length as well as number of portal tracts were recorded. We compared rates of prespecified clinical outcomes of hepatic decompensation and hepatocellular carcinoma across individual Ishak fibrosis stages. Of 1050 biopsy specimens, 25% were fragmented, 63% longer than 1.5 cm, 69% larger than 10 mm 2 , and 75% had 10 or more portal tracts. Baseline laboratory markers of liver disease severity were worse and the frequency of esophageal varices higher with increasing Ishak stage ( P < 0.0001). The 6-year cumulative incidence of first clinical outcome was 5.6% for stage 2, 16.1% for stage 3, 19.3% for stage 4, 37.8% for stage 5, and 49.3% for stage 6. Among nonfragmented biopsy specimens, the predictive ability of Ishak staging was enhanced; however, no association was observed between Ishak stage and outcomes for fragmented biopsy specimens because of high rates of outcomes for patients with noncirrhotic stages. Similar results were observed with liver transplantation or liver-related death as the outcome. Conclusion : Ishak fibrosis stage predicts clinical outcomes, need for liver transplantation, and liver-related death in patients with chronic hepatitis C. Patients with fragmented biopsy specimens with low Ishak stage may be understaged histologically. (H EPATOLOGY 2010;51:585–594.)Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/64929/1/23315_ftp.pd

The burden of selected digestive diseases in the United States

AbstractBackground & Aims: Gastrointestinal (GI) and liver diseases inflict a heavy economic burden. Although the burden is considerable, current and accessible information on the prevalence, morbidity, and cost is sparse. This study was undertaken to estimate the economic burden of GI and liver disease in the United States for use by policy makers, health care providers, and the public. Methods: Data were extracted from a number of publicly available and proprietary national databases to determine the prevalence, direct costs, and indirect costs for 17 selected GI and liver diseases. Indirect cost calculations were purposefully very conservative. These costs were compared with National Institutes of Health (NIH) research expenditures for selected GI and liver diseases. Results: The most prevalent diseases were non–food-borne gastroenteritis (135 million cases/year), food-borne illness (76 million), gastroesophageal reflux disease (GERD; 19 million), and irritable bowel syndrome (IBS; 15 million). The disease with the highest annual direct costs in the United States was GERD ($9.3 billion), followed by gallbladder disease ($5.8 billion), colorectal cancer ($4.8 billion), and peptic ulcer disease ($3.1 billion). The estimated direct costs for these 17 diseases in 1998 dollars were $36.0 billion, with estimated indirect costs of$22.8 billion. The estimated direct costs for all digestive diseases were $85.5 billion. Total NIH research expenditures were$676 million in 2000. Conclusions: GI and liver diseases exact heavy economic and social costs in the United States. Understanding the prevalence and costs of these diseases is important to help set priorities to reduce the burden of illness.GASTROENTEROLOGY 2002;122:1500-151

A randomized controlled trial of pretransplant antiviral therapy to prevent recurrence of hepatitis C after liver transplantation

Hepatitis C virus (HCV) infection recurs in liver recipients who are viremic at transplantation. We conducted a randomized, controlled trial to test the efficacy and safety of pretransplant pegylated interferon alpha‐2b plus ribavirin (Peg‐IFN‐α2b/RBV) for prevention of post‐transplant HCV recurrence. Enrollees had HCV and were listed for liver transplantation, with either potential living donors or Model for End‐Stage Liver Disease upgrade for hepatocellular carcinoma. Patients with HCV genotypes (G) 1/4/6 (n = 44/2/1) were randomized 2:1 to treatment (n = 31) or untreated control (n = 16); HCV G2/3 (n=32) were assigned to treatment. Overall, 59 were treated and 20 were not. Peg‐IFN‐α2b, starting at 0.75 μg/kg/week, and RBV, starting at 600 mg/day, were escalated as tolerated. Patients assigned to treatment versus control had similar baseline characteristics. Combined virologic response (CVR) included pretransplant sustained virologic response and post‐transplant virologic response (pTVR), defined as undetectable HCV RNA 12 weeks after end of treatment or transplant, respectively. In intent‐to‐treat analyses, 12 (19%) assigned to treatment and 1 (6%) assigned to control achieved CVR ( P = 0.29); per‐protocol values were 13 (22%) and 0 (0%) ( P = 0.03). Among treated G1/4/6 patients, 23 of 30 received transplant, of whom 22% had pTVR; among treated G2/3 patients 21 of 29 received transplant, of whom 29% had pTVR. pTVR was 0%, 18%, and 50% in patients treated for 16 weeks, respectively ( P = 0.01). Serious adverse events (SAEs) occurred with similar frequency in treated versus untreated patients (68% versus 55%; P = 0.30), but the number of SAEs per patient was higher in the treated group (2.7 versus 1.3; P = 0.003). Conclusion : Pretransplant treatment with Peg‐IFN‐α2b/RBV prevents post‐transplant recurrence of HCV in selected patients. Efficacy is higher with >16 weeks of treatment, but treatment is associated with increased risk of potentially serious complications. (H EPATOLOGY 2013)Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/97469/1/25976_ftp.pd