Background & Aims Few studies have examined factors associated with disease progression in hepatitis C virus (HCV) infection. We examined the association of 11 risk factors with adverse outcomes in a population-based prospective cohort observational study of Alaska Native/American Indian persons with chronic HCV infection. Methods We collected data from a population-based cohort study of liver-related adverse outcomes of infection in American Indian/Alaska Native persons with chronic HCV living in Alaska, recruited from 1995 through 2012. We calculated adjusted hazard ratios (aHR) and 95% CIs for end-stage liver disease (ESLD; presence of ascites, esophageal varices, hepatic encephalopathy, or coagulopathy), hepatocellular carcinoma (HCC), and liver-related death using a Cox proportional hazards model. Results We enrolled 1080 participants followed for 11,171 person-years (mean, 10.3 years); 66%, 19%, and 14% were infected with HCV genotypes 1, 2, and 3, respectively. On multivariate analysis, persons infected with HCV genotype 3 had a significantly increased risk of developing all 3 adverse outcomes. Their aHR for ESLD was 2.1 (95% CI, 1.5–3.0), aHR for HCC was 3.1 (95% CI, 1.4–6.6), and aHR for liver-related death was 2.4 (95% CI, 1.5–4.0) compared to genotype 1. Heavy alcohol use was an age-adjusted risk factor for ESLD (aHR, 2.2; 95% CI, 1.6–3.2), and liver-related death (aHR: 2.9; 95% CI, 1.8–4.6). Obesity was a risk factor for ESLD (aHR, 1.4; 95% CI, 1.0–1.9, and diabetes was a risk factor for ESLD (aHR, 1.5; 95% CI, 1.1–2.2). Male sex was a risk factor for HCC (aHR, 3.6; 95% CI, 1.6–8.2). Conclusions In a population-based cohort study of American Indian/Alaska Native persons with chronic HCV infection, we found those infected with HCV genotype 3 to be at high risk for ESLD, HCC, and liver-related death.

Long-term prospective studies of the outcomes associated with HCV infection are rare and critical for assessing the potential impact of HCV treatment. Using liver biopsy as a start point, we looked at development of end stage liver disease (ESLD), hepatocellular carcinoma (HCC) and liver-related death (LRD) according to fibrosis stage, among a cohort of American Indian/Alaska Native persons in Alaska. Persons were classified as having no/mild (Ishak=0,1), moderate (Ishak=2), or severe (Ishak=3,4) fibrosis or cirrhosis (Ishak=5,6). We examined time until development of ESLD, HCC and LRD and report survival probabilities at 3, 5, 7 and 10-years. Of 407 persons, 39%(n = 150) had no/mild fibrosis, 32%(n = 131) had moderate fibrosis, 22%(n = 88) had severe fibrosis and 9%(n = 38) had cirrhosis. The average time of follow-up was 7.3 years. Within 5 years of biopsy, 1.7% (95% confidence interval (CI):0.4,6.8) of persons with none/mild fibrosis developed ESLD compared to 7.9% (CI:4.0,15.2), 16.4% (CI:9.6,27.2) and 49.0% (CI:33.0,67.7) with moderate, severe fibrosis, and cirrhosis, respectively (p<0.01). The 5-year outcome of HCC was 1.0% (CI:0.1,7.0), 1.0% (CI 0.1,6.6), 1.1% (CI:0.2,7.7) and 13.4% (CI:4.4,36.7) among persons with none/mild, moderate fibrosis, severe fibrosis and cirrhosis, respectively (p<0.01). Five years following biopsy, 0.0% (CI:0.0,14.8) of persons with none/mild fibrosis had suffered an LRD compared to 1.0% (CI:0.2,7.5) of persons with moderate fibrosis, 4.7% (CI:1.5,14.1) with severe fibrosis and 16.3% (CI:7.0,35.1) with cirrhosis (p<0.01). Conclusion For prevention of HCC, LRD and ESLD in the short-term, HCV therapy should target those with more than mild fibrosis.

Most persons with chronic hepatitis C virus (HCV) infection in the United States are undiagnosed or linked to care. We describe a program for the management of Alaska Native patients infection utilizing a computerized registry and statewide liver clinics resulting in higher linkage to care (86%) than national estimates (~25%).

Background Chronic hepatitis C virus (HCV) infection diminishes immune function through cell exhaustion and repertoire alteration. Direct acting antiviral (DAA)-based therapy can restore immune cell subset function and reduce exhaustion states. However, the extent of immune modulation following DAA-based therapy and the role that clinical and demographic factors play remain unknown. Methods We examined natural killer (NK) cell, CD4+, and CD8+ T cell subsets along with activation and exhaustion phenotypes across an observational study of sofosbuvir-based treatment for chronic HCV infection. Additionally, we examined the ability of clinical variables and duration of infection to predict 12 weeks of sustained virologic response (SVR12) immune marker outcomes. Results We show that sofosbuvir-based therapy restores NK cell subset distributions and reduces chronic activation by SVR12. Likewise, T cell subsets, including HCV-specific CD8+ T cells, show reductions in chronic exhaustion markers by SVR12. Immunosuppressive CD4+ regulatory T cells decrease at 4-weeks treatment and SVR12. We observe the magnitude and direction of change in immune marker values from pretreatment to SVR12 varies greatly among participants. Although we observed associations between the estimated date of infection, HCV diagnosis date, and extent of immune marker outcome at SVR12, our regression analyses did not indicate any factors as strong SVR12 outcome predictors. Conclusion Our study lends further evidence of immune changes following sofosbuvir-based therapy. Further investigation beyond SVR12 and into factors that may predict posttreatment outcome is warranted.

Chronic hepatitis C virus (HCV) infection reduces immune function through exhaustion and repertoire reduction. Sofosbuvir-based direct-acting antiviral (DAA) therapies offer &gt;90% sustained virologic response (SVR) for HCV infection, but the extent of immune recovery and relationship with clinical factors are unknown. The longitudinal Alaska Hepatitis C Cohort provides an opportunity to evaluate immune recovery following sofosbuvir-based DAA and determine the influence of an extensive clinical and laboratory history. Forty-two persons (genotype 1; mean age 50 ± 12 years; 69% female) received 8 or 12-week sofosbuvir-based DAA therapy. Mean HCV RNA detection date was 2007 (range: 1994–2017). Pre-treatment HCV RNA levels averaged 4.9×106 IU/L (range: 4.9×104–2.4×107), were not detectable in any person after 4-weeks of therapy, and all achieved SVR. 18% (n=7) of persons had a fibrosis score of ≥F2 (moderate fibrosis to cirrhosis). Peripheral blood mononuclear cells (PBMCs) were evaluated at four time points: Pre-treatment (Pre), 4-weeks treatment (4wk), End of Treatment (EOT), and SVR post 12-weeks EOT (SVR-12) by flow cytometry to evaluate memory, exhaustion, and functional immune markers. Initial analysis revealed a significant increase in the CD4:CD8 from 4wk to EOT (p=0.007). Regulatory T-cells significantly increased at EOT and SVR-12 compared to 4wk (p=0.04 and 0.03, respectively). TIGIT showed a significant increasing trend in T-cells and NK cells throughout sampling timeline. Preliminary analysis indicates sofosbuvir-based DAA supports immune recovery to some extent. Additional analysis of immune recovery markers, determination of estimated date of HCV infection, and correlation of morbidity factors continues.