Hepatitis C virus infection: opportunities for an earlier detection in primary care

An overview of methodological flaws of real-world studies investigating drug safety in the post-marketing setting

INTRODUCTION

The evaluation of the post-marketing safety profile of drugs is a continuous monitoring process for approved and marketed medicines and it is crucial for detecting new adverse drug reactions. As such, real-world studies are essential to complement pre-marketing evidence with information concerning drug risk-benefit profile and use in wider patient populations and they have a great potential to support post-marketing drug safety evaluations.

AREAS COVERED

A detailed description of the main limitations of real-world data sources (i.e. claims databases, electronic healthcare records, drug/disease registers and spontaneous reporting system databases) and of the main methodological challenges of real-world studies in generating real-world evidence is provided.

EXPERT OPINION

Real-world evidence biases can be ascribed to both the methodological approach and the specific limitations of the different real-world data sources used to carry out the study. As such, it is crucial to characterize the quality of real-world data, by establishing guidelines and best practices for the assessment of data fitness for purpose. On the other hand, it is important that real-world studies are conducted using a rigorous methodology, aimed at minimizing the risk of bias.

Global burden of primary liver cancer by five etiologies and global prediction by 2035 based on global burden of disease study 2019

BACKGROUND

Using data from the global burden of disease (GBD) between 1990 and 2019 to report the leading etiological factors and hazards for liver cancer by HBV (LCHB), HCV (LCHC), alcoholic use (LCAL), NASH (LCNA), and other causes (LCOT).

METHOD

The estimated annual percentage change (EAPC) and age-standardized incidence rate (ASR) in different districts, sex, and age are used to quantify the change of etiologies of liver cancer. Age-period-cohort models were performed to predict the primary liver cancer incidence and case numbers.

RESULTS

Based on the GBD database of the whole world for the five etiologies of liver cancer in 2019, the percentage of incidence of LCAL, LCHB, LCHC, LCNA, and LCOT are 18.4%, 41%, 28.5%, 6.8%, and 5.3%, respectively. Fiver etiologies of liver cancer show gender differences, with LCHB and LCAL being more prevalent in men, and LCHC, LCNA being more prevalent in women. Besides, live cancer of males is because of alcohol using and smoking, while the reason of liver cancer of females is drug use, high BMI and high fasting plasma glucose. Interestingly, the incidence of LCHC in women over 85 years old, LCNA in women over 75 years old, and LCOT in women over 75 years old were all higher than that in men. According to the future prediction, the incidence rate of liver cancer itself, as well as the five causes of liver cancer, tends to decrease gradually after 2019, while the incidence rate of LCNA in males will continue to increase until 2025.

CONCLUSIONS

The incidence of liver cancer has been increasing and its major causes vary considerably at global, regional, or national levels, also vary by gender and age group.

Determinants of HCV-related complications in Italian primary care patients

BACKGROUND AND AIMS

This study aimed to assess the demographic and clinical determinants of liver complications in Hepatitis C virus (HCV)-positive patients in primary care setting.

METHODS

Using the Health Search database, we selected a cohort of patients aged ≥14 diagnosed with HCV between 2002 and 2017. Patients were followed up until the occurrence of cirrhosis and other disease progressions such as oesophageal varices, hepatocellular carcinoma and/or liver transplantation. The candidate determinants for the risk of HCV-related complications included sex, age, smoking status, liver fibrosis (measured by fibrosis 4 index [FIB-4]), infections by the human immunodeficiency virus (HIV), hepatitis B virus (HBV), other forms of hepatitis, abuse of alcohol or illicit substances or drugs, obesity, metabolic syndrome, diabetes mellitus and renal disease. Cox regression was used to test the association between candidate determinants and the outcome.

RESULTS

The cohort included 8299 HCV-positive patients (50.93% men) with an overall prevalence rate equal to 0.61%. At least one HCV-related complication was found in 12.2% of patients, with a mean time-to-event equal to 8.1 year. Along with male sex and advanced age, a FIB-4 greater than 3.25 and the presence of diabetes were associated with a greater risk of HCV-related complications.

CONCLUSION

Our study shows that patients with certain demographics and clinical characteristics are more prone to incur in HCV-related complications. The knowledge and early identification of these determinants by GPs may result in reducing disease progression and related healthcare costs through a closer monitoring.

Estimated prevalence of undiagnosed HCV infected individuals in Italy: A mathematical model by route of transmission and fibrosis progression

BACKGROUND

The universal treatment of diagnosed patients with chronic HCV infection has been widely conducted in Italy since 2017. However, the pool of individuals diagnosed but yet to be treated in Italy has been estimated to end around 2025, leaving a significant proportion of infected individuals undiagnosed/without care. Estimates of this population are currently unknown.

METHODS

A probabilistic modelling approach was applied to estimate annual historical HCV incident cases by their age-group (0-100 years) distribution from available literature and Italian National database (1952 to October 2019). Viraemic infection rates were modelled on the main infection routes in Italy: people who inject drugs (PWID), tattoos, sexual transmission, glass syringe use, blood transfusion and vertical transmission. Annual liver fibrosis stage transition probabilities were modelled using a Markov model. The number of HCV viraemic asymptomatic (fibrosis stage F0-F3:potentially undiagnosed/unlinked to care) and symptomatic (fibrosis stage F4: potentially linked to care) individuals was estimated.

RESULTS

By October 2019, total viraemic HCV individuals in Italy (excluding treated patients since 1992) were estimated to be 410,775 (0.68 % of current population of Italy; 95 % CI: 0.64-0.71%, based on the current Italian population), of which 281,809 (0.47 %; 95 % CI:0.35-0.60%) were fibrosis stage F0-F3. Among different high risk groups in stage F0-F3, the following distribution was estimated: PWID; 52.0 % (95 % CI:37.9-66.6 %), tattoo; 28.8 % (95 % CI:23-32.3 %), sexual transmission; 12.0 % (95 % CI:9.6-13.7 %), glass syringe and transfusion; 6.4 % (95 % CI:2.4-17.8 %), and vertical transmission; 0.7 % (95 % CI:0.4-1.2 %).

CONCLUSION

Under the assumption that most untreated HCV-infected individuals with stage F0-F3 are undiagnosed, more than 280,000 individuals are undiagnosed and/or unlinked to care in Italy. Marked heterogeneity across the major routes of HCV transmission was estimated. This modelling approach may be a useful tool to characterise the HCV epidemic profile also in other countries, based on country specific epidemiology and HCV main transmission routes.

Screening, Linkage to Care and Treatment of Hepatitis C Infection in Primary Care Setting in the South of Italy

Hepatitis C virus (HCV) infection remains a pressing public health issue. Our aim is to assess the linkage to care of patients with HCV diagnosis and to support the proactive case-finding of new HCV-infected patients in an Italian primary care setting. This was a retrospective cohort study of 44 general practitioners (GPs) who managed 63,955 inhabitants in the Campania region. Adults with already known HCV diagnosis or those with HCV high-risk profile at June 2019 were identified and reviewed by GPs to identify newly diagnosed of HCV and to assess the linkage to care and treatment for the HCV patients. Overall, 698 HCV patients were identified, 596 with already known HCV diagnosis and 102 identified by testing the high-risk group (2614 subjects). The 38.8% were already treated with direct-acting antivirals, 18.9% were referred to the specialist center and 42.3% were not sent to specialist care for treatment. Similar proportions were found for patients with an already known HCV diagnosis and those newly diagnosed. Given that the HCV infection is often silent, case-finding needs to be proactive and based on risk information. Our findings suggested that there needs to be greater outreach, awareness and education among GPs in order to enhance HCV testing, linkage to care and treatment.

Predictive factors for not undergoing RNA testing in patients found to have hepatitis C serology and impact of an automatic alert

The process of diagnosis and linkage to care in cases of hepatitis C virus (HCV) infection remains an obstacle to disease control. The aims of this study were to evaluate predictive factors for not undergoing RNA testing among patients with positive HCV serology and impact of incorporating an automated electronic alert with recommendations in clinical practice. We collected HCV antibody tests requested from October 2011 to September 2014 to evaluate the rate of RNA testing and predictive factors for not undergoing RNA testing. Since October 2014, an automated alert notification has been implemented to remind physicians for testing RNA after a positive HCV test and referral to specialist care. 41 403 HCV antibody tests were requested from 34 073 patients. 870 (2.55%) patients tested positive. After a median of follow-up of 57.0 months (range 45.6-82.1), 37.6% did not have RNA testing. The independent predictors for not undergoing RNA testing were primary care serology requests (P < 0.001), no history of drug use (P = 0.005) and a lack of social support (P = 0.015). The intervention impact was evaluated in a pre-alert cohort (October 2011-September 2014) and a post-alert cohort (October 2014-September 2015). After the incorporation of the alert, the rate of RNA testing increased from 62.4% to 77.7% (P < 0.001). Incomplete assessment of HCV infection is a challenge in primary care. The implementation of an automated alert for recommending RNA testing after a positive HCV antibody test is feasible in clinical practice and increases the rate of patients with RNA testing.

Changing seroprevalence of hepatitis C virus infection among HIV-positive patients in Taiwan

Objective

The study aimed to describe the evolution of the seroprevalence of hepatitis C virus (HCV) among human immunodeficiency virus (HIV)-positive patients included in two cohorts in Taiwan.

Methods

We retrospectively collected the information on demographic and clinical characteristics of 4,025 and 3,856 HIV-positive Taiwanese, who were aged 18 years or older at designated hospitals around Taiwan in 2004–2007, when an outbreak of HIV infection was occurring, and 2012–2016, when the outbreak was controlled with the implementation of harm reduction program, respectively. Comparisons of HCV seropositivity were made among different age and risk groups for HIV transmission between these two cohorts.

Results

The overall HCV seroprevalence of the 2004–2007 cohort and 2012–2016 cohort was 43.4% (1,288/2,974) and 18.6% (707/3,793), respectively (P<0.001). The HCV seroprevalence among injecting drug users (IDUs), though decreasing, was constantly high across the two cohorts, 96.4% and 94.0% (P = 0.02), respectively, and all age groups. In contrast, the corresponding figures among men who have sex with men (MSM) and heterosexuals in the two cohorts were 5.9% vs. 3.5% (P = 0.002) and 9.4% vs. 10.9% (P = 0.59), respectively. Among sexually transmitted HIV-positive patients, HCV seropositivity was significantly correlated with age (adjusted odds ratio [aOR], per 1-year increase, 1.03; 95% confidence interval [CI], 1.02–1.05) and a rapid plasma reagin (RPR) titer ≥1:8 (aOR, 1.58; 95% CI, 1.03–2.43) in a multivariate analysis including age, gender, route for HIV transmission, baseline CD4 count and plasma HIV RNA load, the presence of hepatitis B surface antigen, and an RPR titer ≥1:8. Compared with heterosexuals, the aOR for HCV seropositivity among MSM was 0.47 (95% CI, 0.31–0.72).

Conclusions

HCV seroprevalence among HIV-positive patients in Taiwan decreased with time, probably related to the inclusion of younger adults and more non-IDUs, and remained high among IDUs. HCV seropositivity was associated with age and an RPR titer ≥1:8 among patients who acquired HIV through sexual contact.

Epidemiology, patient profile, and health care resource use for hepatitis C in Italy

Objective

The objectives of this study were to estimate the prevalence of Hepatitis C among six Italian Local Health Units (LHUs), to describe patient and antiviral drug characteristics, and to estimate the health care consumption rates and related costs for the management of patients affected by hepatitis C virus (HCV) infection by using data from routine clinical practice.

Methods

We conducted a retrospective study using administrative databases of six Italian LHUs. All patients who had a record related to HCV during the enrollment period (July 1, 2009, to December 31, 2014) and who had at least 6 months of data available prior to the first HCV record were included. The date of the first record related to HCV during the enrollment period was considered as a proxy of diagnosis and used as the index date. Patients were followed from the index date up to 1 year, death, or exiting the database. Using the overall cohort of HCV adult patients as the numerator, we estimated the prevalence of HCV among six LHUs. The denominators were obtained from the National Institute of Statistics (N=1,665,682). We also evaluated descriptive patient’s characteristics and treatment patterns, and estimated health care consumption rates and related costs for the management of the HCV patients.

Results

A total of 7,550 patients were analyzed, of whom 57% were male with a mean age of 57.6±16.4 years. The prevalence of HCV was estimated to be 0.45% (95% confidence interval 0.44–0.46). During the follow-up period, 78.6% of HCV patients had received no antiviral treatment. The annual health care cost associated with HCV infection was €6,022.7 (±7,922.6) while the cost specific to HCV care was €3,154.6 (±4,972.0)

Conclusion

Our findings showed that, in the Italian real-world setting, only a small proportion of HCV-infected patients received an antiviral treatment. Despite the current low prevalence of HCV, the economic impact of such disease remains high.