Hepatitis C Virus Screening and Prevalence Among US Veterans in Department of Veterans Affairs Care

From 2.7 to 3.9 million Americans are living with hepatitis C virus (HCV) infection, and 45% to 85% are unaware they are infected.^1-4 In August 2012, the Centers for Disease Control and Prevention (CDC) began recommending 1-time HCV screening for persons born from 1945 through 1965 because this group encompasses 75% of those infected.⁵ We assessed the extent to which veterans, particularly those born during the 1945-1965 period, were screened for HCV and estimated HCV prevalence.

This retrospective cohort analysis used the US Department of Veteran’s Affairs (VA) Corporate Data Warehouse, which includes VA laboratory test results from October 1, 1999, onward. The cohort includes veterans with at least 1 VA outpatient visit in 2011. We accepted HCV antibody, viral load, and genotype tests as evidence of screening and calculated rates as of December 31, 2011. Confirmatory RNA testing counted genotype or viral load testing for those with positive antibody test results. Anti-HCV prevalence and HCV infection prevalence were estimated from those veterans with informative laboratory results.

A total of 5 415 084 veterans had VA outpatient visits in 2011, and 2 889 385 (53.4%) had VA HCV screening. The HCV screening rate was 40.6% for those born before 1945, 63.5% for those born during the 1945-1965 period, and 57.0% for those born after 1965 (eTable in the Supplement). The confirmatory RNA testing rate was 94.7% overall (eTable in the Supplement). Anti-HCV prevalence in over 2.8 million veterans was 8.4% and varied by birth cohort (Table). Prevalence of HCV infection was 6.2% and varied by birth cohort: 1.7% for those born before 1945, 10.3% for those born during the 1945-1965 period, and 1.1% for those born after 1965 (Table). By birth year, HCV infection prevalence peaked at 18.4% in those born in 1954 (Figure). Prevalence of HCV infection was higher in men (6.5%) than in women (2.8%) and was highest in blacks (12.3%), followed by Hispanics (6.7%) and American Indians/Alaska Natives (6.6%). Within each sex and race/ethnicity group, HCV infection prevalence was highest in those born during the 1945-1965 period, much lower in those born before 1945, and generally lowest in those born after 1965. Among men born from 1945 through 1965, prevalence ranged from 18.2% in blacks to 3.5% in Asians (eFigure 1A in the Supplement); although prevalence in black women was highest (5.7%), prevalence was appreciably lower with less variation across race/ethnicity subgroups in women (eFigure 1B in the Supplement).

Among 5.4 million veterans, which represents the entire Veteran population in VA care and laboratory results spanning 12 years, over half of the entire cohort and two-thirds of those born during the 1945-1965 period had VA HCV screening prior to the updated CDC recommendation. In this highly screened population, anti-HCV prevalence (8.4%) was higher than the previous estimate for the veteran population (5.4%), likely due to the increasing proportion of the high prevalence in the 1945-1965 cohort over time.⁶ Anti-HCV prevalence in the 1945-1965 birth cohort (13.5%) was markedly higher than in veterans born before (2.9%) or after (1.8%) and was 4 times higher than the 3.25% anti-HCV prevalence for this birth cohort from NHANES data (National Health and Nutrition Examination Survey).⁵ As expected from the elevated anti-HCV prevalence, HCV infection prevalence was elevated in the veteran 1945-1965 birth cohort (10.3%) compared to other veteran birth cohorts and well above the estimated 2.4% prevalence in this birth cohort in the general US population.⁵ This high HCV infection prevalence in the 1945-1965 birth cohort substantiates the disproportionate disease burden that underpins the CDC recommendation for birth cohort screening and supports the birth cohort emphasis. The observed high HCV infection prevalence—relative to prior VA estimates and general population estimates—serves as a reminder of the greater HCV disease burden in the veteran population. Given the high HCV infection prevalence, full adoption of birth cohort screening may reveal substantial numbers of veterans with previously unknown HCV infection.

Corresponding Author: Lisa I. Backus, MD, PhD, Office of Public Health/Population Health, 3801 Miranda Ave, Mail Code #132, Palo Alto, CA 94304 (lisa.backus@va.gov).

Published Online: July 8, 2013. doi:10.1001/jamainternmed.2013.8133.

Conflict of Interest Disclosures: None reported.