P2404 - Hepatitis C Genotypes in the United States, Data from the National Health & Nutrition Examination Survey (2011-2020)

Karthik Gnanapandithan, MD, MS¹, Maged P. Ghali, MD^2
1Mayo Clinic Florida, Jacksonville, FL; ²University of Florida, Jacksonville, FL

Introduction: Hepatitis C virus (HCV) is a leading cause of liver-related morbidity and mortality. HCV exhibits high genetic diversity, with six major genotypes distributed differently worldwide. The natural history, response to treatment, and outcomes vary between the genotypes. Using a nationally representative sample from the National Health and Nutrition Examination Survey (NHANES), we looked at the distribution of HCV genotypes and the liver function tests in the different genotypes.

Methods: The study included 266 adults (20 years and older) with chronic HCV infection who participated in the NHANES between 2011 and March 2020. Those with positive HCV RNA were considered infected. Interview data and laboratory values were used in the study. The VERSANT HCV Genotype 2.0 Assay, a line probe assay, identifies HCV genotypes in the serum samples. Sas 9.4 survey package was used to calculate the weighted percentage of each genotype in the HCV-infected US population and the average liver function tests between them. Appropriate sample weights were used to account for unequal selection probabilities given the NHANES sampling model.

Results: A total of 266 HCV-infected adults participated in the survey. Genotype 1a was the most common, with a weighted percentage of 60.2%, followed by genotypes 2 and 3 at 15.9% and 12.2%, respectively (Table 1). Aspartate transaminase levels were highest in those with genotype 3 (71.3 U/L), followed by genotype 1 (62.9 U/L). Alanine transaminase levels were also highest in subjects with genotype 3 (78.7 U/L), followed by genotype 1 (64.4 U/L). The differences in enzyme levels between the genotypes did not reach statistical significance (p-values of 0.08 and 0.14). Alkaline phosphatase, total bilirubin, and serum albumin levels showed no noticeable difference.

Discussion: Genotype 1a is the most common accounts for 60% of HCV infections in the US. There is inadequate information on the association between the disease progression of HCV and the genotype. Prior studies have shown higher steatosis and progression to fibrosis with genotype 3. Our analysis also indicates that the transaminase elevation is more in those with genotype 3. We need more studies to throw light on the pathophysiology of different HCV genotypes. Although the treatment algorithm focuses primarily on the degree of fibrosis with a pan-genotypic regimen, the genotype must be considered for treatment and follow-up duration.


Disclosures:


Karthik Gnanapandithan, MD, MS¹, Maged P. Ghali, MD². P2404 - Hepatitis C Genotypes in the United States, Data from the National Health & Nutrition Examination Survey (2011-2020), ACG 2023 Annual Scientific Meeting Abstracts. Vancouver, BC, Canada: American College of Gastroenterology.