A Big Step Forward in Hepatitis C Screening

Short abstract

http://aasldpubs.onlinelibrary.wiley.com/hub/journal/10.1002/(ISSN)2046-2484/video/15-4-reading-kapila a video presentation of this article

Abbreviations

AASLD

Association for the Study of Liver Diseases

ACOG

American College of Obstetrics and Gynecology

CDC

Centers for Disease Control and Prevention

DAA

directing‐acting antiviral agent

HCV

hepatitis C virus

IDSA

Infectious Diseases Society of America

SVR

sustained virological response

USPSTF

US Preventive Services Task Force

Despite the development of highly effective directing‐acting antiviral agents (DAAs), the United States is struggling in its efforts to eliminate hepatitis C virus (HCV). Along the HCV treatment cascade from diagnosis through treatment and cure, the lack of awareness of the diagnosis by many patients remains a major challenge. The US Preventive Services Task Force (USPSTF) recently released a draft statement that would expand HCV screening to adults aged 18 to 79 years.1 The Centers for Disease Control and Prevention (CDC),2 the American Association for the Study of Liver Diseases (AASLD), and the Infectious Diseases Society of America (IDSA) HCV guidance panel3 followed with similar recommendations to expand HCV screening. This review will examine the current state of HCV screening and the impact of these new recommendations.

Current State of HCV Screening

HCV infection is the most common chronic bloodborne pathogen in the United States, with an estimated prevalence between 2 and 4 million.4 Nearly half of patients infected with HCV are unaware of their disease,5, 6 thus leading to a delay in diagnosis and risks of late presentations with the life‐threatening complications of cirrhosis and hepatocellular carcinoma.

The initial approach to screening for HCV focused on risk factors, including injection drug use and past receipt of blood products.7 A systematic review of studies from this era revealed that only 50% of persons with HCV infection were aware of the diagnosis.8 One reason for the failure of this strategy was the stigma associated with injection drug use. An alternative screening strategy was guided by research that found that approximately 75% of persons living with HCV in the United States were from the baby boomer generation.9 Therefore, in 2012, the CDC recommended HCV screening for Americans born between 1945 and 1965 in addition to risk‐based screening.10 The USPSTF and the AASLD/IDSA Guidance Panel later endorsed this recommendation.11, 12

This baby boomer screening strategy emerged as highly effective DAAs were introduced. Previous interferon‐containing regimens were poorly tolerated, lacked efficacy, and required prolonged treatment. HCV DAA regimens have achieved high rates of sustained virological response (SVR) in clinical trials and real‐world cohorts. SVR is synonymous with cure and is associated with improved quality of life, morbidity, liver‐related mortality, and all‐cause mortality.13, 14, 15, 16 Despite these advances, modest increases have been observed in the number of individuals screened for HCV. A study of the National Health and Nutrition Examination Survey showed screening among baby boomers increased from 12.3% in 2013 to 17.3% in 2017.17 A 2019 study reported only 52% of persons with HCV in the United States were aware of the diagnosis.18

In a draft statement released in August 2019, the USPSTF issued revised recommendations for HCV screening in adults.1 The revised recommendations included one‐time screening for adults aged 18 to 79 years, continued periodic screening for individuals at high risk, and routine HCV screening in pregnant women.

Universal Screening: The Impact of the Opioid Epidemic

In their analysis that led to this recommendation for screening all adults, the USPSTF considered the benefits of treatment and the impact of the opioid epidemic on HCV. The past decade has seen a sharp increase in the incidence of HCV in young, nonurban adults.19, 20 Between 2004 and 2014, the CDC reported a nearly 4‐fold increase in acute HCV among young adults. This sharp increase in young adults infected with HCV coincides with a nationwide surge in the rate of injection drug use.21 Individual states have reported an increase in HCV, and in many of these states the number of young patients with HCV outnumbers baby boomers.22 Modeling studies have now demonstrated the cost‐effectiveness of expanded HCV screening.23, 24, 25 These models predict that universal screening increases the number of patients who are diagnosed and cured of HCV and is cost‐effective compared with the current standard of care. Expanding to universal screening is expected to increase the rate of HCV diagnosis to 77% by 2030 (Fig. 1).18 The USPSTF’s draft statement acknowledges the evolving landscape of HCV by expanding screening to include previously excluded young adults who have been impacted disproportionally by the opioid epidemic.

Figure 1.

The cascade of awareness of HCV by patients.6, 18

Screening in Pregnancy

The CDC observed that the number of women of reproductive age with HCV doubled from 2006 to 2014.26 The proportion of infants born to HCV‐infected mothers has also increased sharply.27 In Kentucky, one of several states particularly impacted by the opioid epidemic, the rates of HCV detection in women of childbearing age and children younger than 2 years increased by more than 200% and 151%, respectively.

The American College of Obstetrics and Gynecology (ACOG) recommends screening for pregnant women only with risk factors for HCV infection.28, 29 This is in part due to the lack of US Food and Drug Administration–approved antiviral therapy for pregnant women. This recommendation contrasts with that of the AASLD/IDSA guidance panel, which in 2018 endorsed screening of all pregnant women irrespective of risk factors.30 The shifting epidemiology of HCV in women of childbearing age, the risk for vertical transmission,31 the impact of HCV on pregnancy outcomes,32 and the increasing access to DAAs prompted the USPSTF to include screening for all pregnant women in their draft recommendations.

What is Next?

The AASLD/IDSA recently supported universal HCV screening for all adults, as well as pregnant women, irrespective of risk factors.3 The CDC has also proposed universal HCV screening for adults and pregnant women, however only when the prevalence rate of HCV is greater than 0.1%.2 This approach, although believed to be cost‐effective, may ultimately prove challenging to administer. It is not clear how HCV prevalence will be determined and ultimately communicated to the local communities. Ultimately, the USPSTF, CDC, and AASLD‐IDSA recognize the shifting epidemiology of HCV and acknowledge the safety and efficacy of DAA therapy.

If this draft statement is endorsed by the USPSTF, efforts will be required to identify and screen all adults aged 18 to 79 years. One potential area of controversy is the recommendation for HCV screening in pregnancy, and it will be important to see whether ACOG alters their position and expands screening for pregnant patients. Approving the recommendations outlined in the draft statement is an important step to increase awareness, provide treatment, and ultimately eliminate HCV.