Pulmonary alterations in patients with chronic HCV infection

Hepatitis C Virus Clearance and Diffusing Capacity for Carbon Monoxide in Women With and Without Human Immunodeficiency Virus

Hepatitis C virus (HCV) infection is associated with extrahepatic effects, including reduced diffusing capacity of the lungs. It is unknown whether clearance of HCV infection is associated with improved diffusing capacity. In this sample of women with and without human immunodeficiency virus, there was no association between HCV clearance and diffusing capacity.

Association between viral hepatitis and metabolic syndrome in lung function impairment: A Taiwan community-based study

OBJECTIVES

Metabolic syndrome (MetS) and hepatitis C virus (HCV) are associated with a higher risk of impaired pulmonary function (iPF). This study aimed to investigate the relationships among MetS, iPF, and viral hepatitis.

METHODS

This community-based study enrolled participants undergoing annual health check-ups in southern Taiwan between March and December 2019. We performed multivariable logistic regression analyses adjusted for demographics and characteristics to identify the factors associated with iPF.

RESULTS

A total of 2337 participants completed examinations, of whom 928 (39.7%) had iPF. The participants with iPF were elderly (68.8  ±  12.8 years old) and predominately female (63%). MetS increased the risk of iPF (odds ratio (OR) 1.51, 95% confidence interval (CI) 1.27-1.81, p < 0.001). Beyond age (OR 1.03, 95% CI 1.02-1.04) and smoking (OR 1.309, 95% CI 1.004-1.705), female sex (OR 0.74, 95% CI 0.59-0.93) and high education level (OR 0.96, 95% CI 0.94-0.98, p < 0.001) protected against iPF. HCV was not significantly associated with iPF (OR 1.17, 95% CI 0.90-1.52, p  =  0.235) in multivariable analysis. MetS was associated with a higher risk of iPF in the non-HBV/HCV group (OR 1.86, 95% CI 1.54-2.26) and HBV alone group (OR 3.44, 95% CI 1.89-6.28), but not in the HCV alone group (OR 1.02, 95% CI 0.64-1.62).

DISCUSSION

MetS was an independent predictor of iPF, especially the restrictive type, and had different effects in the HBV/non-viral hepatitis and HCV groups. Female sex and education were inversely associated with iPF.

Chronic viral hepatitis accelerates lung function decline in smokers

Although hepatitis B virus (HBV) and hepatitis C virus (HCV) are hepatotrophic viruses, they may affect pulmonary diseases. The purpose of this study was to assess whether chronic viral hepatitis (CVH) infection was associated with a rapid decline in lung function. Repeated measurements of lung function were obtained from a well-curated health check-up database. A case was defined as an individual positive for HBsAg or anti-HCV antibody. A control was randomly selected (from the same dataset) after 1:1 matching in terms of age, sex, height, the body mass index, and smoking status. Separate analyses of non-smokers and smokers were performed. A total of 701 cases were enrolled (586 with HBV and 115 with HCV). In cross-sectional analysis, both forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC) decreased significantly only in smokers (smoking cases vs. smoking controls) (adjusted p = 6.6 × 10-5 and adjusted p = 2.2 × 10-3, respectively). In longitudinal analysis, smoking cases showed significantly greater FEV1 and FVC decline rates than did smoking controls (adjusted p = 8.5 × 10-3 and adjusted p = 1.2 × 10-5, respectively). Such associations were particularly high in smoking cases at intermediate-to-high risk of hepatic fibrosis, as evaluated by the non-invasive Fibrosis-4 index. In summary, CVH was associated with both decreased lung function and accelerated lung function decline in smokers. A non-invasive measurement of hepatic fibrosis may be useful in predicting rapid lung function decline in smokers with CVH.

Lung Function in Women With and Without Human Immunodeficiency Virus

BACKGROUND

Prior studies have found that human immunodeficiency virus (HIV) infection is associated with impaired lung function and increased risk of chronic lung disease, but few have included large numbers of women. In this study, we investigate whether HIV infection is associated with differences in lung function in women.

METHODS

This was a cross-sectional analysis of participants in the Women's Interagency HIV Study, a racially and ethnically diverse multicenter cohort of women with and without HIV. In 2018-2019, participants at 9 clinical sites were invited to perform spirometry. Single-breath diffusing capacity for carbon monoxide (DLCO) was also measured at selected sites. The primary outcomes were the post-bronchodilator forced expiratory volume in 1 second (FEV1) and DLCO. Multivariable regression modeling was used to analyze the association of HIV infection and lung function outcomes after adjustment for confounding exposures.

RESULTS

FEV1 measurements from 1489 women (1062 with HIV, 427 without HIV) and DLCO measurements from 671 women (463 with HIV, 208 without HIV) met standards for quality and reproducibility. There was no significant difference in FEV1 between women with and without HIV. Women with HIV had lower DLCO measurements (adjusted difference, -0.73 mL/min/mm Hg; 95% confidence interval, -1.33 to -.14). Among women with HIV, lower nadir CD4 + cell counts and hepatitis C virus infection were associated with lower DLCO measurements.

CONCLUSIONS

HIV was associated with impaired respiratory gas exchange in women. Among women with HIV, lower nadir CD4 + cell counts and hepatitis C infection were associated with decreased respiratory gas exchange.

Chronic Hepatitis B Infection in Children and Its Relation to Pulmonary Function Tests: A Case-control Study

BACKGROUND

The aim of this study was to evaluate the pulmonary function test (PFT) abnormalities, if any, in children with newly diagnosed chronic hepatitis B (CHB) infection over 3 years.

METHODS

This is an observational case-control study. One hundred children and adolescents with newly diagnosed CHB were enrolled as the patient group that was further subdivided into 2 groups (50 patients each): inactive carriers (group I) and patients in immunotolerant phase (group II). Only 90 patients completed the study. Fifty healthy children of matched age, sex and height served as a control group, only 45 of them completed the study. PFTs in the form of forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), FEV1/FVC, residual volume, total lung capacity, mid-forced expiratory flow of 25%-75% and diffusing capacity of the lung for carbon monoxide were evaluated in all studied children at the start, yearly and at the end of the study after 3 years. Liver function tests were also evaluated.

RESULTS

There was a significant progressive decrease in FEV1, FVC, forced expiratory flow, total lung capacity and diffusing capacity of the lung for carbon monoxide in CHB patient groups compared with their pulmonary functions at the start of the study and with the control group (P < 0.05), while FEV1/FVC and residual volume showed nonsignificant change (P > 0.05).

CONCLUSIONS

Subclinical PFT abnormalities are present in children with CHB more than we expected. So, PFT monitoring is recommended in pediatric patients with CHB.

Chronic Obstructive Pulmonary Disease and Hepatitis C

Chronic obstructive pulmonary disease (COPD) is a preventable, treatable disease with significant extrapulmonary manifestations that could affect negatively its course in some patients. Hepatitis C virus infection (HCV), on the other hand, is associated with a number of extrahepatic manifestations. COPD patients have increased prevalence of HCV and patients with HCV, especially older ones, have increased prevalence and faster progression of COPD. HCV infection exerts long-term effects on lung tissue and is an additional risk factor for the development of COPD. The presence of HCV is associated with an accelerated loss of lung function in COPD patients, especially in current smokers. COPD could represent extrahepatic manifestation associated with HCV infection. The aim of this article was to review the literature on prevalence of HCV in COPD and vice versa, pathogenetic link and the consequences of their mutual existence.

The impact of hepatitis C viremia status on lung functions in chronic hepatitis c patients

BACKGROUND

Previous trials have investigated the effect of hepatitis C on lung functions; however, the role of viral load levels is unclear. The aim of this study was to investigate the effect of HCV viremia status on lung functions.

METHODS

This study was in 60 patients with chronic hepatitis C (CHC). Patients were classified into three groups (non-viremic, low-viremic and high-viremic) based on serum HCV RNA levels. Spirometric parameters (FEV1, FVC, FEV1/FVC) and the proportion of patients with spirometric abnormalities were compared between three groups.

RESULTS

High-viremic and low-viremic patients showed a significantly higher prevalance of spirometric abnormality than observed in non-viremic patients (p=0.02). Moreover, there was a significant moderate correlation between viremia level and the percentage of spirometric abnormalities (Cramer's U value=0.452, p=0.002). High-viremic patients were 14.2 times more likely to exhibiting pulmonary dysfunction than non-viremic patients. Additionally, spirometric parameters FEV1 and FVC were significantly reduced in high-viremic and low-viremic patients compared to those in non-viremic patients (p=0.013 and p<0.001 respectively).

CONCLUSION

These results indicate that persistent HCV infection may be associated with reduced pulmonary functions, especially in patients with high viremia levels. Therefore, these patients should be carefully monitored for lung function.

Non-specific impairment of Lung Function on Spirometery in Patients with Chronic Hepatitis-C

Objectives:

To document frequency of non-specific impairment of lung functions (NILF) in patients of HCV and to compare according to gender, genotype, liver fibrosis score and smoking status.

Methods:

Patients of chronic hepatitis C were included after informed consent. Demographic data was recorded, and they underwent baseline investigations, fibroscan, abdominal ultrasound and PFT. Patients were segregated on basis of gender, fibroscan stages and smoking status. NILF was labelled if any two of three criteria are fulfilled (a) FVC < 80% of Predicted, (b) FEV1 < 80% Predicted, (c) FEV1/FVC ≥ 70.

Results:

Two hundred thirty four patients were of chronic HCV who fulfilled the selection criteria were inducted in study. These included 49.6% males and 50.4% females. There were 15.0% smokers, 16.2% were ex-smokers while 68.8% were never smokers. NILF was present in 130 (55.6%) out of which 61.5% were female and 38.5% were male (p <0.001), its presence in smokers was 56.2% and in never smokers was 55.3% (p=0.507). Presence of NILF increased with Fibroscan stages from F1 to F4 (p <0.001).

Conclusions:

NILF pattern on spirometry with normal chest radiograph is common among HCV patients. It was found more common in females and frequency increased progressively with fibro scan stages.

Hepatitis C Virus-Associated Extrahepatic Manifestations in Lung and Heart and Antiviral Therapy-Related Cardiopulmonary Toxicity

Besides liver cirrhosis and hepatocellular carcinoma, chronic hepatitis C virus (HCV) infection is associated with many extrahepatic manifestations (EHMs). HCV exhibits lymphotropism that is responsible for various EHM. An important characteristic of HCV is escape from the immune system, which enables it to produce chronic infections and autoimmune disorders along with accumulation of circulating immune complexes. These EHMs have large spectrum, because they affect many organs such as heart, lungs, kidney, brain, thyroid, and skin. HCV-related cardiac and pulmonary manifestations include myocarditis, cardiomyopathies, cardiovascular diseases (i.e., Stroke, ischemic heart disease), chronic obstructive pulmonary disease, idiopathic pulmonary fibrosis, asthma, and interstitial lung diseases. This review discusses etiology and pathogenesis of HCV-associated cardiac and pulmonary manifestations and how different genes, immune system, indirectly linked factors (mixed cryoglobulinemia), liver cirrhosis, and antiviral treatment are involved in HCV-related heart and lung diseases, however, their exact mechanism is not clear.

The association of exposure to hepatitis B and C viruses with lung function and respiratory disease: a population based study from the NHANES III database

BACKGROUND

Globally, 500 million people are chronically infected with Hepatitis B virus (HBV) and Hepatitis C virus (HCV). While these viruses are notorious for their detrimental effect on the liver they are also known to affect multiple organs in the body including the lungs.

AIM

To investigate if exposure to HBV and HCV is associated with lung function and respiratory diseases.

METHODS

Data from the Third National Health and Nutrition Examination Survey (NHANES III) was analysed using multiple linear regressions to investigate the association between exposure to HBV and HCV with the various measures of lung function, while multiple logistic regressions were used to evaluate the association with the respiratory diseases asthma and chronic obstructive pulmonary disease (COPD).

RESULTS

Exposure to HCV was significantly associated with an increase in Forced Expiratory Volume in 1 s, FEV1 (Coef: 97.94 ml, 95% CI: 38.87 to 157.01) and Full Vital Capacity, FVC (Coef: 90 ml, 95% CI: 14.50 to 166.24). Individuals who had been exposed to both HBV and HCV also had a significantly higher FEV1 (Coef: 145.82, CI: 60.68 to 230.94) and FVC (Coef: 195.09, CI: 78.91 to 311.26). There was also a significant association between exposure to HBV and asthma (OR: 1.28, 95% CI: 1.05 to 1.58). These associations were no longer significant after additionally adjusting for cocaine and marijuana use as well as poverty income ratio.

CONCLUSION

Our research implies that hepatotropic viruses may affect the respiratory system, but more work at a population level is needed to further explore these associations.

A Study of the Interaction between Hepatitis C Virus Infection and Pulmonary Disorders: Assessment of Interferon Gamma and Alpha-1-Antitrypsin

Objectives: To study lung diseases in chronic HCV infection and vice versa and to find immunological and/or hereditary interrelating factors.Material and Methods: Study included 134 individuals, all were subjected to screening for anti-HCV antibodies by ELISA, HCV-RNA by real time PCR, pulmonary function tests, quantitative assay of interferon gamma and alpha-1- antitrypsin in serum by ELISA and genotyping of alpha-1- antitrypsin gene by Light Cycler PCR.Results: 76.5% of chronic HCV patients had abnormal PFT (P = 0.03), mainly reduced DLCO and reversible airway obstruction, and 41.6% of chest diseased patients were HCV-positive with a significant decrease in large and small airways functions. Interferon therapy improved PFT parameters. Only 33% of chronic HCV infection affected by chest abnormality responded to interferon therapy while 50% of chest free patients did. Serum IFN-γ was higher in HCV and chest patients than in control (P=0.02). All serum α1AT deficient patients had M/null genotype.Conclusions: A pathogenic role of chronic HCV infection in lung diseases is evident. Interferon treatment may reduce chest complications and improve pulmonary functions. However, chest affection may reduce the response to interferon treatment. M/null genotype of α1AT gene might play a role in chronic HCV infection and chest co-affection.

Gas exchanges and pulmonary vascular abnormalities at different stages of chronic liver disease

BACKGROUND

It is unclear whether and to which extent respiratory function abnormalities may complicate the earliest stages of chronic liver disease (CLD). Aim of this study was to compare pulmonary capillary volumes and gas exchange efficiency of CLD patients with and without cirrhosis.

METHODS

Sixty-seven participants (mean age 56.5 years; women 22.4%) were divided into three groups (matched by age, sex, smoking) according to the baseline CLD stage as follows: (a) healthy controls (Group A, n=20); (b) non-cirrhotic CLD patients (Group B; n=23); (c) cirrhotic CLD patients (Group C; n=24). All participants underwent clinical assessment, respiratory function tests, gas exchange estimation by the alveolar diffusion of carbon monoxide (TLCO) measurement and 6-min walking test. Groups were compared by chi-square and one-way anova tests.

RESULTS

Chronic liver disease patients had significantly lower levels of TLCO (Group B=17.7 ml/min mmHg, and Group C=14.2 ml/min mmHg) compared with healthy controls (Group A=24.4 ml/min mmHg). Consistent results were obtained when analyses were performed using TLCO expressed as percentage of the predicted value. TLCO adjusted for the alveolar volume was lower in cirrhotic patients compared with both controls and non-cirrhotic CLD patients (P<0.001 and P=0.035 respectively). Group C participants presented blood gas parameters tending to a compensated chronic respiratory alkalosis status compared with the other groups.

CONCLUSIONS

Pulmonary microvascular and gas exchange modifications are present at early stages of CLD. Future studies should be focused at evaluating the pathophysiological mechanisms underlying this relationship.