COPD in HIV-Infected Patients: CD4 Cell Count Highly Correlated

Identification of Oxidative Stress-Associated Biomarkers in Chronic Obstructive Pulmonary Disease: An Integrated Bioinformatics Analysis

Purpose

Chronic obstructive pulmonary disease (COPD) is among the three leading causes of death worldwide, with its prevalence, morbidity, and mortality rates increasing annually. Oxidative stress (OS) is a key mechanism in COPD development, making the identification of OS-related biomarkers beneficial for improving its diagnosis and treatment.

Methods

The genetic data from patients with COPD and controls were obtained from the Gene Expression Omnibus database to identify OS-related genes (OSRGs). Functional enrichment analysis was conducted using the Kyoto encyclopedia of genes and genomes signaling pathway and gene ontology (GO). Protein-protein interaction networks were constructed to identify the core genes, which were further evaluated using receiver operating characteristic (ROC) curves. Diagnostic models were developed based on the core genes. Besides, the correlation between the expression of the core genes and the immune cells was analyzed using single-sample gene set enrichment analysis. Drug-gene interactions were explored to predict target drugs, and related microribonucleic acid (miRNA) and transcription factors (TFs) were identified using miRNet.

Results

In this study, we identified 299 differential genes, including 16 OSRGs. Among these, five core genes-heat shock protein family A (Hsp70) member 1A (HSPA1A), glutamate-cysteine ligase modifier subunit, interleukin-1 beta (IL-1β), intercellular adhesion molecule 1 (ICAM1), and glutamate-cysteine ligase catalytic subunit (GCLC)-were screened and validated using ROC curve analysis. The results of GO enrichment analysis were mainly focused on the OS response, the negative regulation of the exogenous apoptosis signaling pathway, and the regulation of the apoptosis signaling pathway. Additionally, 33 target drugs were predicted, including ofloxacin, cisplatin, and pegolimumab, among others. Meanwhile, the regulatory networks comprising 33 miRNAs related to the core genes and 38 TFs associated with HSPA1A, IL-1β, ICAM1, and GCLC were constructed. A diagnostic model based on the five genes was constructed and validated with an area under the curve of 0.981 (95% confidence interval: 0.941-1.000).

Conclusion

This study identifies potential biomarkers for diagnosing COPD, new potential targets, and new directions for drug development and treatment.

Effect of Human Immunodeficiency Virus on Lung Function and Structure: A Systematic Review and Meta-Analysis

Rationale: Obstructive lung disease (OLD) pathogenesis includes inhalational (e.g., smoking) and noninhalational mechanisms (e.g., infections). Human immunodeficiency virus (HIV) has been suggested as a novel OLD risk factor. Substantial data have recently emerged about its effects on lung function and structure, especially in low- to middle-income countries and regarding longitudinal lung function. Objectives: To assess the association of HIV infection with OLD, impaired gas exchange, and emphysema. Methods: In this systematic review and meta-analysis, we searched PubMed, Embase, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, Web of Science, Scopus, Cumulative Index to Nursing and Allied Health Literature, and Global Index Medicus through April 2023 for controlled and observational studies of people living with and without HIV reporting pulmonary function and/or emphysema. Primary outcomes were OLD by spirometry, gas exchange impairment by diffusing capacity of the lung for carbon monoxide, and visual emphysema by computed tomography. We performed random-effects meta-analyses using odds ratios (ORs) with 95% confidence intervals (CIs). This study was registered in PROSPERO (CRD42021268498). Results: We included 95 publications pertaining to 43 unique studies. HIV was associated with OLD (OR, 1.29; 95% CI, 1.02-1.63), impaired gas exchange (OR, 2.63; 95% CI, 0.96-7.24), emphysema (OR, 1.46; 95% CI, 1.02-2.09), and faster lung function decline. OLD risk was greatest in Africans with HIV. There were no gas exchange or emphysema data from Africa. The certainty of evidence was low to very low, primarily because of studies' observational design. Conclusions: People living with HIV have increased risk for OLD, gas exchange impairment, faster lung function decline, and emphysema. OLD risk in HIV varies regionally. We recommend that both spirometry and diffusing capacity of the lung for carbon monoxide be measured in people living with HIV and respiratory symptoms. Future studies should develop and validate HIV-specific screening and case-finding strategies for chronic lung disease.

Analysis of Predictive Value of Cellular Inflammatory Factors and T Cell Subsets for Disease Recurrence and Prognosis in Patients with Acute Exacerbations of COPD

Objective

To explore the predictive value of cellular inflammatory factors and T cell subsets for disease recurrence and prognosis in patients with acute exacerbations of chronic obstructive pulmonary disease (COPD).

Methods

Serum samples were collected from the two groups to detect and compare the levels of inflammatory cytokines [interleukin-1β (IL-1β), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α)], T cell subsets (CD4+, CD8+), and clinical related indicators. Pearson correlation analysis was used to analyze the correlation between inflammatory cytokines, T cell subsets, and clinical indicators. Receiver operating characteristic (ROC) curves were plotted to analyze the predictive value of serum inflammatory factors and T cell subsets for acute exacerbations of COPD.

Results

The observation group had higher levels of IL-1β, IL-6, TNF-α, and CD8+, and lower CD4+ levels (P<0.05). The ratio of forced expiratory volume in 1 second to forced vital capacity (FEV1/FVC) was lower, while procalcitonin (PCT) and white blood cell count (WBC) were higher (P<0.05). Correlation analysis showed positive correlations between IL-1β, IL-6, TNF-α, and CD8+, and negative correlations with CD4+ and FEV1/FVC (P<0.05). After 6 months, 15 out of 73 patients had acute recurrences, with higher IL-1β, IL-6, TNF-α, and CD8+ levels (P<0.05). Binary logistic regression identified IL-1β, IL-6, TNF-α, and CD8+ as significant predictors of exacerbations, while CD4+ was protective. ROC analysis showed that combined biomarkers had the highest predictive efficiency (AUC = 0.907).

Conclusion

This study is the first to integrate multiple serum inflammatory factors and T cell subsets into a comprehensive predictive model for acute recurrence of COPD within six months (AUC = 0.907), offering a more accurate prediction than traditional methods. The findings underscore the value of these biomarkers in clinical follow-up and highlight their independent predictive power, providing new insights into the interaction between immune markers and clinical indicators in COPD exacerbations.

Post tuberculosis lung disease and tuberculosis sequelae: A narrative review

Post Tuberculosis lung disease (PTLD) and post tuberculosis sequelae is a global and poorly recognized problem, amplified by social factors and immunocompromising conditions, inadequate treatment, lack of effective prevention of tuberculosis (TB) infection and disease. As a disease, it remained until recently poorly defined, with studies heterogenous with regards to regions, population demographics, risk factors, cohort sizes, and methods. Pathophysiologically, even successfully treated pulmonary TB disease has sequelae i.e. involving central and peripheral airways, lung parenchyma and pleura, resulting in airway narrowing and dilatation, fibrocavitation and emphysema, pulmonary vascular changes as well as pleural fibrosis. Functionally patients have airflow limitation, restrictive disease or a mixture of both not rarely associated with respiratory, or even ventilatory failure. Quality of life is often impaired through disability, TB relapse, superinfections and through increased susceptibility to reinfection and persistent inflammation, leading to progressive lung function decline and an increased risk of cardiovascular disease and cancer. Premature mortality due to PTLD is very likely, but poorly described.

COPD in People with HIV: Epidemiology, Pathogenesis, Management, and Prevention Strategies

Chronic obstructive pulmonary disease (COPD) is a progressive respiratory disorder characterized by airflow limitation and persistent respiratory symptoms. People with HIV (PWH) are particularly vulnerable to COPD development; PWH have demonstrated both higher rates of COPD and an earlier and more rapid decline in lung function than their seronegative counterparts, even after accounting for differences in cigarette smoking. Factors contributing to this HIV-associated difference include chronic immune activation and inflammation, accelerated aging, a predilection for pulmonary infections, alterations in the lung microbiome, and the interplay between HIV and inhalational toxins. In this review, we discuss what is known about the epidemiology and pathobiology of COPD among PWH and outline screening, diagnostic, prevention, and treatment strategies.

HIV-associated lung disease

Lung disease encompasses acute, infectious processes and chronic, non-infectious processes such as chronic obstructive pulmonary disease, asthma and lung cancer. People living with HIV are at increased risk of both acute and chronic lung diseases. Although the use of effective antiretroviral therapy has diminished the burden of infectious lung disease, people living with HIV experience growing morbidity and mortality from chronic lung diseases. A key risk factor for HIV-associated lung disease is cigarette smoking, which is more prevalent in people living with HIV than in uninfected people. Other risk factors include older age, history of bacterial pneumonia, Pneumocystis pneumonia, pulmonary tuberculosis and immunosuppression. Mechanistic investigations support roles for aberrant innate and adaptive immunity, local and systemic inflammation, oxidative stress, altered lung and gut microbiota, and environmental exposures such as biomass fuel burning in the development of HIV-associated lung disease. Assessment, prevention and treatment strategies are largely extrapolated from data from HIV-uninfected people. Smoking cessation is essential. Data on the long-term consequences of HIV-associated lung disease are limited. Efforts to continue quantifying the effects of HIV infection on the lung, especially in low-income and middle-income countries, are essential to advance our knowledge and optimize respiratory care in people living with HIV.

Magnetic-activated cell sorting identifies a unique lung microbiome community

BACKGROUND

The advent of culture-independent, next-generation DNA sequencing has led to the discovery of distinct lung bacterial communities. Studies of lung microbiome taxonomy often reveal only subtle differences between health and disease, but host recognition and response may distinguish the members of similar bacterial communities in different populations. Magnetic-activated cell sorting has been applied to the gut microbiome to identify the numbers and types of bacteria eliciting a humoral response. We adapted this technique to examine the populations of immunoglobulin-bound bacteria in the lung.

METHODS

Sixty-four individuals underwent bronchoalveolar lavage (BAL). We separated immunoglobulin G-bound bacteria using magnetic-activated cell sorting and sequenced the 16S rRNA gene on the Illumina MiSeq platform. We compared microbial sequencing data in IgG-bound bacterial communities compared to raw BAL then examined the differences in individuals with and without HIV as a representative disease state.

RESULTS

Immunoglobulin G-bound bacteria were identified in all individuals. The community structure differed when compared to raw BAL, and there was a greater abundance of Pseudomonas and fewer oral bacteria in IgG-bound BAL. Examination of IgG-bound communities in individuals with HIV demonstrated the differences in Ig-bound bacteria by HIV status that were not seen in a comparison of raw BAL, and greater numbers of immunoglobulin-bound bacteria were associated with higher pulmonary cytokine levels.

CONCLUSIONS

We report a novel application of magnetic-activated cell sorting to identify immunoglobulin G-bound bacteria in the lung. This technique identified distinct bacterial communities which differed in composition from raw bronchoalveolar lavage, revealing the differences not detected by traditional analyses. Cytokine response was also associated with differential immunoglobulin binding of lung bacteria, suggesting the functional importance of these communities. Video Abstract.

Pneumoproteins and biomarkers of inflammation and coagulation do not predict rapid lung function decline in people living with HIV

Chronic obstructive pulmonary disease (COPD) is among the leading causes of death worldwide and HIV is an independent risk factor for the development of COPD. However, the etiology of this increased risk and means to identify persons with HIV (PWH) at highest risk for COPD have remained elusive. Biomarkers may reveal etiologic pathways and allow better COPD risk stratification. We performed a matched case:control study of PWH in the Strategic Timing of Antiretoviral Treatment (START) pulmonary substudy. Cases had rapid lung function decline (> 40 mL/year FEV₁ decline) and controls had stable lung function (+ 20 to - 20 mL/year). The analysis was performed in two distinct groups: (1) those who were virally suppressed for at least 6 months and (2) those with untreated HIV (from the START deferred treatment arm). We used linear mixed effects models to test the relationship between case:control status and blood concentrations of pneumoproteins (surfactant protein-D and club cell secretory protein), and biomarkers of inflammation (IL-6 and hsCRP) and coagulation (d-dimer and fibrinogen); concentrations were measured within ± 6 months of first included spirometry. We included an interaction with treatment group (untreated HIV vs viral suppression) to test if associations varied by treatment group. This analysis included 77 matched case:control pairs in the virally suppressed batch, and 42 matched case:control pairs in the untreated HIV batch (n = 238 total) who were followed for a median of 3 years. Median (IQR) CD4 + count was lowest in the controls with untreated HIV at 674 (580, 838). We found no significant associations between case:control status and pneumoprotein or biomarker concentrations in either virally suppressed or untreated PWH. In this cohort of relatively young, recently diagnosed PWH, concentrations of pneumoproteins and biomarkers of inflammation and coagulation were not associated with subsequent rapid lung function decline.Trial registration: NCT00867048 and NCT01797367.

HIV and chronic lung disease

PURPOSE OF REVIEW

As people living with human immunodeficiency virus (HIV, PLWH) age, aging-related comorbidities have come into focus as major challenges to their overall health. In this review, an in-depth overview of the two most commonly encountered chronic lung diseases in PLWH, chronic obstructive pulmonary disease (COPD) and lung cancer, is provided.

RECENT FINDINGS

The risk for both COPD and lung cancer remains significantly higher in PLWH compared to the HIV-uninfected population, although fortunately rates of lung cancer appear to be declining over the last two decades. Outcomes for PLWH with these conditions, though, continue to be poor with worse survival rates in comparison to the general population. PLWH still face major barriers in accessing care for these conditions, including a higher likelihood of being underdiagnosed with COPD and a lower likelihood of being referred for lung cancer screening or treatment. A lack of evidence for optimal treatment strategies for both COPD and lung cancer still hampers the care of PLWH with these conditions.

SUMMARY

COPD and lung cancer represent substantial burdens of disease in PLWH. Improved access to standard-of-care screening and treatment and greater investigation into therapeutic responses specifically in this population are recommended.

Chronic obstructive pulmonary disease in never-smokers: risk factors, pathogenesis, and implications for prevention and treatment

Chronic obstructive pulmonary disease (COPD) was traditionally thought to be caused by tobacco smoking. However, recognition of the importance of non-smoking-related risk factors for COPD has increased over the past decade, with evidence on the burden, risk factors, and clinical presentations of COPD in never-smokers. About half of all COPD cases worldwide are due to non-tobacco-related risk factors, which vary by geographical region. These factors include air pollution, occupational exposures, poorly controlled asthma, environmental tobacco smoke, infectious diseases, and low socioeconomic status. Impaired lung growth during childhood, caused by a range of early-life exposures, is associated with an increased risk of COPD. Potential mechanisms for the pathogenesis of COPD in never-smokers include inflammation, oxidative stress, airway remodelling, and accelerated lung ageing. Compared with smokers who develop COPD, never-smokers with COPD have relatively mild chronic respiratory symptoms, little or no emphysema, milder airflow limitation, and fewer comorbidities; however, exacerbations can still be frequent. Further research-including epidemiological, translational, clinical, and implementation studies-is needed to address gaps in understanding and to advance potential solutions to reduce the burden of COPD in never-smokers.

Altered polarization and impaired phagocytic activity of lung macrophages in people with HIV and COPD

BACKGROUND

People with HIV (PWH) have an increased risk of developing Chronic Obstructive Pulmonary Disease (COPD).

METHODS

We phenotyped lung macrophages in four subgroups: M1 (CD40+CD163-), M2 (CD40-CD163+), Double Positives (CD40+CD163+), Double Negatives (CD40-CD163-) and determined their phagocytic capacity in PWH with and without COPD.

RESULTS

PWH with COPD have more double negative macrophages (84.1%) vs PWH without (54.3%) vs controls (23.9%) (p=0.004) and reduced phagocytosis (p=0.012). Double negative macrophages had the worst phagocytic capacity (p<0.001).

CONCLUSIONS

PWH with COPD have an abundance of non-polarized macrophages which have poor phagocytic capacity therefore predispose them to increased risk of disease progression.

Predictors of impaired pulmonary function in people living with HIV in an urban African setting

Background

Studies have associated HIV with an increased risk of obstructive lung disease (OLD).

Objectives

We aimed to identify the predictive factors for impaired lung function in an urban, African, HIV-positive population.

Method

A cross-sectional study was performed in Johannesburg, South Africa, from July 2016 to November 2017. A questionnaire was administered and pre- and post-bronchodilator spirometry conducted. The predictors investigated included age, sex, antiretroviral treatment (ART) duration, body mass index, history of tuberculosis (TB) or pneumonia, occupational exposure, environmental exposure, smoking and symptoms of OLD (cough, wheeze, mucus and dyspnoea). Impaired lung function was defined as a forced expiratory volume in 1 second/forced vital capacity (FEV1/FVC) ratio of < 0.70, or below the 20th percentile of normal.

Results

The 98 ART-naïve participants (mean age = 34.0, standard deviation [s.d.] = 8.2), 85 participants on first-line ART (mean age = 36.9, s.d. = 6.6) and 189 participants on second-line ART (mean age = 43.5, s.d. = 7.9) were predominantly female (65.6%). Of the participants, 64 (17.2%) had impaired lung function and 308 had normal lung function. Linear regression identified age (β = –0.003, P < 0.01), male sex (β = –0.016, P = 0.03) and history of TB or pneumonia (β = –0.024, P < 0.01) as independent predictors of a lower FEV1/FVC ratio. Following logistic regression, only a history of TB or pneumonia (odds ratio = 2.58, 95% confidence interval = 1.47–4.52) was significantly related to impaired lung function (area under the receiver operating characteristic curve = 0.64).

Conclusion

Our data show that a history of TB or pneumonia predicts impaired lung function. In order to improve timely access to spirometry, clinicians should be alert to the possibility of impaired lung function in people with a history of TB or pneumonia.

Incidence of chronic obstructive pulmonary disease in people with HIV, their parents and siblings in Denmark

BACKGROUND

People with HIV (PWH) may be at increased risk of several respiratory syndromes including chronic obstructive pulmonary disease (COPD). In matched cohort studies, we examined risk factors for COPD in PWH, their parents and siblings compared with population controls.

METHODS

Using data from national registries, competing risk regression models were constructed and used to calculate adjusted hazard ratios (aHR) for COPD. We evaluated the effect of HIV characteristics, smoking and educational attainment on COPD incidence in PWH.

RESULTS

A total of 226 PWH and 1029 population controls were diagnosed with COPD during 63,661 and 562,171 person years of follow up. PWH had increased risk of being diagnosed with COPD compared to controls (aHR 2.02 [95%CI: 1.75-2.33]). Parents and siblings of PWH were also more likely to be diagnosed with COPD compared to controls. CD4+ T-cell counts were not associated with COPD, but both unsuppressed viral replication, smoking status and educational attainment were associated with COPD in PWH. No COPD diagnoses were registered in PWH with high educational attainment and absence of smoking.

CONCLUSIONS

PWH have an increased risk of being diagnosed with COPD, as have their parents and siblings. This seems to be driven primarily by smoking and low socioeconomic status.

Chronic obstructive pulmonary disease in HIV

Introduction: Chronic obstructive pulmonary disease (COPD) is more prevalent in people with HIV (PWH) than in the general population and leads to an increased burden of morbidity and mortality in this population. The mechanisms behind COPD development and progression in PWH are not fully elucidated, and there are no PWH-specific guidelines for COPD management. Areas covered: The goal of this broad narrative review is to review the epidemiology of COPD in PWH globally, highlight proposed pathways contributing to increased COPD prevalence and progression in PWH, discuss structural and functional changes in the lungs in this population, assesses the excess mortality and comorbidities in PWH with COPD, and address management practices for this unique population. Expert opinion: Understanding how a chronic viral infection leads to COPD, independent of cigarette smoking, is of critical scientific importance. Further research should focus on the pathophysiology of the interaction between HIV and COPD, and determine the role of disease-modifying risk factors such as opportunistic pneumonia and air pollution, as well as generate data from randomized clinical trials on the safety and efficacy of specific therapies for this vulnerable patient population.

Respiratory symptoms and chronic bronchitis in people with and without HIV infection

OBJECTIVES

High rates of respiratory symptoms and chronic bronchitis (CB) are reported in people with HIV infection (PWH). We investigated the prevalence of respiratory symptoms and CB in PWH and HIV-negative people in the Pharmacokinetic and clinical Observations in PeoPle over fiftY (POPPY) study.

METHODS

Assessment of respiratory symptoms and CB was undertaken using the modified form of the St. George's Respiratory Questionnaire for chronic obstructive pulmonary disease (COPD). Univariate (χ² tests, Mann-Whitney U tests and Spearman's rank correlation) and multivariable (linear and logistic regression) analyses were performed to consider associations of respiratory symptoms with demographic, lifestyle and HIV-related parameters, and with depressive symptoms and quality of life.

RESULTS

Among the 619 participants, respiratory Symptom scores were higher in older and younger PWH compared to older HIV-negative people, with median (interquartile range) scores of 17.7 (6.2, 39.5), 17.5 (0.9, 30.0) and 9.0 (0.9, 17.5), respectively (P = 0.0001); these differences remained significant after confounder adjustment. Sixty-three participants (10.2%) met the criteria for CB [44 (14.0%) older PWH, 14 (9.2%) younger PWH, and five (3.3%) older HIV-negative people; P = 0.002], with these differences also remaining after adjustment for confounding variables, particularly smoking status [older vs. younger PWH: odds ratio (OR) 4.48 (95% confidence interval (CI) 1.64, 12.30); P = 0.004; older PWH vs. HIV-negative people: OR 4.53 (95% CI 1.12, 18.28); P = 0.03]. Respiratory symptoms and CB were both associated with greater depressive symptom scores and poorer quality of life. No strong associations were reported between CB and immune function, HIV RNA or previous diagnosis of any AIDS event.

CONCLUSIONS

Respiratory symptoms and CB are more common in PWH than in demographically and lifestyle-similar HIV-negative people and are associated with poorer mental health and quality of life.

The elevated systemic cytokine levels in HIV patients are not associated with an elevated pulmonary cytokine environment

BACKGROUND

HIV-positive patients on anti-retroviral therapy (ART) are at higher risk of developing many non-AIDS related chronic diseases, including chronic obstructive pulmonary disease (COPD), compared to HIV-negative individuals. While the mechanisms are not clear, a persistent pro-inflammatory state appears to be a key contributing factor. The aims of this study were to investigate whether HIV-positive patients without COPD present evidence of potentially predisposing abnormal pulmonary cytokine/chemokine environment and to explore the relationship between pulmonary and systemic cytokine levels.

METHODS

This study included 39 HIV-seropositive and 34 HIV-seronegative subjects without COPD. All were subjected to outpatient bronchoscopy with bronchoalveolar lavage fluid (BALF) aspiration and blood sample collection. The levels of 21 cytokines and chemokines were measured in plasma and BALF using a bead-based multi-analyte assay.

RESULTS

In plasma, HIV-infected patients showed significantly increased circulating levels of pro-inflammatory (TNFα) and Th1-associated cytokines (IL-12p70) as well as several chemokines (CXCL11 and CX3CL1). However, no statistically significant differences were found in the numbers of cells, the concentrations of protein and urea as well as cytokine levels in the BALFs of HIV-positive patients when compared to controls. Correlation analysis indicated a potential modulatory effect of the BMI in HIV-seropositive individuals.

CONCLUSIONS

While our results are consistent with the existence of a systemic pro-inflammatory state in HIV-infected patients, they did not detect significant differences in cytokine levels and other inflammatory markers in the lungs of HIV-positive individuals when compared to HIV-negative controls.

Incidence of chronic obstructive pulmonary disease in people with HIV in Ontario, 1996-2015: a retrospective population-based cohort study

BACKGROUND

Because of high smoking rates and HIV-related factors, people with HIV may be at high risk for chronic obstructive pulmonary disease (COPD); however, population-based estimates of the incidence of COPD among people with HIV are lacking, particularly for women. We compared the incidence of COPD among Ontario adults aged 35 years or more with and without HIV between Jan. 1, 1996, and Dec. 31, 2015.

METHODS

We conducted a population-based study using Ontario's health administrative databases. We compared the incidence of COPD between people with and without HIV using standardized incidence ratios and generalized estimating equations with a log link function.

RESULTS

We identified 1849 people with HIV and 1 168 727 HIV-negative people who were newly diagnosed with COPD between 1996 and 2015. People with HIV were younger than HIV-negative people (mean age 49.7 [standard deviation 10.4] yr v. 62.2 [standard deviation 14.8] yr; standardized difference 0.98). Rates of COPD were higher among people with HIV than among HIV-negative people (10.4 v. 9.0 cases per 1000 person-years; standardized incidence ratio 1.16, 95% confidence interval [CI] 1.10 to 1.21; adjusted rate ratio 1.34, 95% CI 1.27 to 1.41). In sex-stratified analyses, rates of COPD were higher among men with HIV (adjusted rate ratio 1.32, 95% CI 1.24 to 1.40) and women with HIV (adjusted rate ratio 1.54, 95% CI 1.37 to 1.72) than among men and women without HIV. In a sensitivity analysis, smoking explained observed differences in COPD incidence.

INTERPRETATION

People with HIV had higher rates of incident COPD than HIV-negative people. This may reflect the disproportionately higher prevalence of smoking among the former.

Obstructive Lung Disease in HIV-Phenotypes and Pathogenesis

PURPOSE OF REVIEW

In the antiretroviral therapy era, people living with HIV (PLWH) are surviving to older ages. Chronic illnesses such as chronic obstructive pulmonary disease (COPD) occur more frequently. COPD is often described as a single entity, yet multiple manifestations may be considered phenotypes. HIV is an independent risk factor for certain COPD phenotypes, and mechanisms underlying pathogenesis of these phenotypes may differ and impact response to therapy.

RECENT FINDINGS

Impaired diffusing capacity, airflow obstruction, and radiographic emphysema occur in PLWH and are associated with increased mortality. Age, sex, tobacco, and HIV-specific factors likely modulate the severity of disease. An altered lung microbiome and residual HIV in the lung may also influence phenotypes. COPD is prevalent in PLWH with multiple phenotypes contributing to the burden of disease. HIV-specific factors and the respiratory microbiome influence disease pathogenesis. As tobacco use remains a significant risk factor for COPD, smoking cessation must be emphasized for all PLWH.

Lung Function, Coronary Artery Disease, and Mortality in HIV

Rationale: Impaired lung function is a potent independent predictor of coronary artery disease (CAD) in individuals without human immunodeficiency virus (HIV) infection; however, the relationship between lung function and CAD in HIV remains undefined. Objectives: To examine the relationship between lung function, CAD, mortality, and circulating biomarkers in HIV. Methods: Spirometry, diffusing capacity of the lung for carbon monoxide (DlCO), emphysema, coronary artery calcium, mortality, cause of death, and biomarkers were examined in HIV-infected and uninfected individuals enrolled in a cohort study at the University of Pittsburgh. Results were then validated in the Multicenter AIDS Cohort Study (MACS) cohort. Results: We examined data on 234 participants in the Pittsburgh cohort. The mean ± standard deviation age was 49.5 ± 10.2 years old, 82.1% were male, and 67.5% were ever smokers. Among the 177 of 234 individuals with HIV infection, lower DlCO (not forced expiratory volume in 1 second or emphysema) was independently associated with greater coronary artery calcium (odds ratio, 1.43 per 10% lower DlCO; 95% confidence interval, 1.14-1.81). HIV-infected individuals with both reduced DlCO and coronary artery calcium had a much higher mortality than those with either low DlCO or coronary calcium alone or with neither condition. Endothelin-1, a circulating biomarker of endothelial dysfunction, was associated with both lower DlCO and greater coronary artery calcium in those with HIV infection. Results were reproducible in 144 individuals enrolled in the MACS cohort; intercellular adhesion molecule 1 was the biomarker of endothelial dysfunction assessed in the MACS cohort. Conclusions: Impaired DlCO and CAD were associated with each other and with higher mortality in individuals with HIV infection.

Associations between baseline biomarkers and lung function in HIV-positive individuals

OBJECTIVE

The aim of this study was to analyse the association of baseline biomarker data with cross-sectional lung function and subsequent decline in lung function in HIV-positive persons.

DESIGN

Lung function was modelled in all START pulmonary substudy participants who had baseline biomarker data and good-quality spirometry. In longitudinal analyses, we restricted to those participants with at least one good-quality follow-up spirometry test.

METHODS

We performed linear regression of baseline forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC) and FEV1/FVC and their longitudinal slopes on log2-transformed baseline biomarkers with adjustment for age, sex, race, region, smoking status, baseline CD4+ T-cell counts and baseline HIV-RNA. Biomarkers included D-dimer, high-sensitivity C-reactive protein (hsCRP), interleukin (IL)-6, IL-27, serum amyloid A, soluble intercellular adhesion molecule (sICAM)-1, soluble vascular cell adhesion molecule (sVCAM)-1, albumin and total bilirubin.

RESULTS

Among 903 included participants, baseline median age was 36 years, CD4+ cell count was 647 cells/μl, and 28.5% were current smokers. In adjusted analyses, elevated markers of systemic inflammation (hsCRP, IL-6 and serum amyloid A) were associated with lower baseline FEV1 and FVC. Elevated D-dimer and IL-6 were associated with worse airflow obstruction (lower FEV1/FVC). Despite these cross-sectional associations at baseline, no associations were found between baseline biomarkers and subsequent longitudinal lung function decline over a median follow-up time of 3.9 years (3293 spirometry-years of follow-up).

CONCLUSION

Commonly available biomarkers, in particular markers of systemic inflammation, are associated with worse cross-sectional lung function, but do not associate with subsequent lung function decline among HIV-positive persons with early HIV infection and baseline CD4 T-cell counts more than 500 cells/μl.

The association between HIV infection and pulmonary function in a rural African population

OBJECTIVES

HIV infection has been associated with an impaired lung function in high-income countries, but the association between HIV infection and pulmonary function in Sub-Saharan Africa remains unclear. This study aims to investigate the relation between HIV infection and pulmonary function in a rural African population.

METHODS

A cross-sectional study was conducted among HIV-positive and HIV-negative adults in a rural area in South Africa, as part of the Ndlovu Cohort Study. A respiratory questionnaire and post-bronchodilator spirometry were performed. Multivariable regression analysis was used to investigate whether HIV was independently associated with a decrease in post-bronchodilator FEV1/FVC ratio considering age, sex, body mass index, respiratory risk factors and a history of a pulmonary infection (tuberculosis (TB) or a pneumonia). Possible mediation by a history of pulmonary infection was tested by removing this variable from the final model.

RESULTS

Two hundred and one consecutive participants were enrolled in the study in 2016, 84 (41.8%) were HIV-positive (82.1% on ART). The median age was 38 (IQR 29-51) years. Following multivariable analysis HIV was not significantly associated to a decline in post-bronchodilator FEV1/FVC ratio (β -0.017, p 0.18). However, upon removal of a history of a pulmonary infection from the final model HIV was significantly related to post-bronchodilator FEV1/FVC ratio, β -0.026, p 0.03.

CONCLUSIONS

Pulmonary function is affected by HIV infection which most likely results from co-infection with TB or other pneumonia. Further research should focus on the influence of a pulmonary infection, most notably TB, on pulmonary function, especially as the incidence of TB is high in HIV infection.

Effects of Tobacco Usage and Antiretroviral Therapy on Biomarkers of Systemic Immune Activation in HIV-Infected Participants

Like HIV infection, smoking, which is common among HIV-infected persons, is associated with chronic, systemic inflammation. However, the possible augmentative effects of HIV infection and smoking and other types of tobacco usage on indices of systemic inflammation and the impact of combination antiretroviral therapy (cART) thereon remain largely unexplored and represent the focus of the current study. Of the total number of HIV-infected persons recruited to the study (n = 199), 100 were categorised as pre-cART and 99 as virally suppressed (HIV viral load < 40 copies/mL). According to serum cotinine levels, 144 and 55 participants were categorised as nonusers and users of tobacco, respectively. In addition to cytokines (IL-6, IL-8, and TNF-α) and chemokines (IP-10, MIG, IL-8, MCP-1, and RANTES), other biomarkers of systemic inflammation included C-reactive protein (CRP), β2-microglobulin, and those of neutrophil activation [ICAM-1, L-selectin, matrix metalloproteinase-9 (MMP-9)], microbial translocation (soluble CD14, LPS-binding protein), and oxidative stress (cyclophilin A, surfactant D). These were measured using multiplex bead array, ELISA, and immunonephelometric procedures. Viral suppression was associated with significant decreases in the levels of most of the biomarkers tested (P < 0.0037-0.0008), with the exceptions of CRP, cyclophilin A, and MMP-9. With respect to tobacco usage, irrespective of cART status, circulating levels of β2-microglobulin, cyclophilin A, and RANTES were significantly elevated (P < 0.042-0.012) in users vs nonusers. Additional analysis of the groups of tobacco users and nonusers according to cART status revealed high levels of RANTES in pre-cART/tobacco users relative to the three other subgroups (P < 0.004-0.0001), while more modest increases in cyclophilin A and MMP-9 (P < 0.019-0.027) were observed in comparison with the cART/tobacco user subgroup. Notwithstanding the efficacy of cART in attenuating HIV-associated, chronic systemic inflammation, the current study has identified RANTES as being significantly and seemingly selectively increased in those with active HIV infection who use tobacco, a mechanism which may underpin augmentative proinflammatory activity.

Cigarette smoke and HIV synergistically affect lung pathology in cynomolgus macaques

In the era of combined antiretroviral therapy (cART), lung diseases such as chronic bronchitis (CB) and chronic obstructive pulmonary disease (COPD) are common among persons living with HIV (PLWH), particularly smokers. Although smoking is highly prevalent among PLWH, HIV may be an independent risk factor for lung diseases; however, the role of HIV and cigarette smoke (CS) and their potential interaction in the development of chronic lung diseases among PLWH has not been delineated. To investigate this interaction, cynomolgus macaques were exposed to CS and/or simian-adapted human immunodeficiency virus (SHIV) and treated with cART. The development of CB and the lung functions were evaluated following CS±SHIV treatment. The results showed that in the lung, SHIV was a strong independent risk factor for goblet cell metaplasia/hyperplasia and mucus formation, MUC5AC synthesis, loss of tight junction proteins, and increased expression of Th2 cytokines/transcription factors. In addition, SHIV and CS synergistically reduced lung function and increased extrathoracic tracheal ring thickness. Interestingly, SHIV infection generated significant numbers of HIV-gp120+ epithelial cells (HGECs) in small airways and alveoli, and their numbers doubled in CS+SHIV-infected lungs. We conclude that even with cART, SHIV independently induces CB and pro-COPD changes in the lung, and the effects are exacerbated by CS.

Comparison of strategies for scalable causal discovery of latent variable models from mixed data

Modern technologies allow large, complex biomedical datasets to be collected from patient cohorts. These datasets are comprised of both continuous and categorical data ("Mixed Data"), and essential variables may be unobserved in this data due to the complex nature of biomedical phenomena. Causal inference algorithms can identify important relationships from biomedical data; however, handling the challenges of causal inference over mixed data with unmeasured confounders in a scalable way is still an open problem. Despite recent advances into causal discovery strategies that could potentially handle these challenges; individually, no study currently exists that comprehensively compares these approaches in this setting. In this paper, we present a comparative study that addresses this problem by comparing the accuracy and efficiency of different strategies in large, mixed datasets with latent confounders. We experiment with two extensions of the Fast Causal Inference algorithm: a maximum probability search procedure we recently developed to identify causal orientations more accurately, and a strategy which quickly eliminates unlikely adjacencies in order to achieve scalability to high-dimensional data. We demonstrate that these methods significantly outperform the state of the art in the field by achieving both accurate edge orientations and tractable running time in simulation experiments on datasets with up to 500 variables. Finally, we demonstrate the usability of the best performing approach on real data by applying it to a biomedical dataset of HIV-infected individuals.

HIV Infection, Pulmonary Tuberculosis, and COPD in Rural Uganda: A Cross-Sectional Study

PURPOSE

HIV is associated with chronic obstructive pulmonary disease (COPD) in high resource settings. Similar relationships are less understood in low resource settings. We aimed to estimate the association between HIV infection, tuberculosis, and COPD in rural Uganda.

METHODS

The Uganda Non-communicable Diseases and Aging Cohort study observes people 40 years and older living with HIV (PLWH) on antiretroviral therapy, and population-based HIV-uninfected controls in rural Uganda. Participants completed respiratory questionnaires and post-bronchodilator spirometry.

RESULTS

Among 269 participants with spirometry, median age was 52 (IQR 48-55), 48% (n = 130) were ever-smokers, and few (3%, n = 9) reported a history of COPD or asthma. All participants with prior tuberculosis (7%, n = 18) were PLWH. Among 143 (53%) PLWH, median CD4 count was 477 cells/mm3 and 131 (92%) were virologically suppressed. FEV1 was lower among older individuals (- 0.5%pred/year, 95% CI 0.2-0.8, p < 0.01) and those with a history of tuberculosis (- 14.4%pred, 95% CI - 23.5 to - 5.3, p < 0.01). COPD was diagnosed in 9 (4%) participants, eight of whom (89%) were PLWH, six of whom (67%) had a history of tuberculosis, and all of whom (100%) were men. Among 287 participants with complete symptom questionnaires, respiratory symptoms were more likely among women (AOR 3.9, 95% CI 2.0-7.7, p < 0.001) and those in homes cooking with charcoal (AOR 3.2, 95% CI 1.4-7.4, p = 0.008).

CONCLUSION

In rural Uganda, COPD may be more prevalent among PLWH, men, and those with prior tuberculosis. Future research is needed to confirm these findings and evaluate their broader impacts on health.

Pulmonary disease in HIV-infected adults in the era of antiretroviral therapy

: HIV in the antiretroviral therapy era is characterized by multimorbidity and the frequent occurrence of HIV-associated non-AIDS chronic health conditions. Respiratory symptoms and chronic pulmonary diseases, including chronic obstructive pulmonary disease, asthma, and cardiopulmonary dysfunction, are among the conditions that may present in persons living with HIV. Tobacco smoking, which is disproportionately high among persons living HIV, strongly contributes to the risk of pulmonary disease. Additionally, features associated with and at times unique to HIV, including persistent inflammation, immune cell activation, oxidative stress, and dysbiosis, may also contribute. This review summarizes the available literature regarding epidemiology of and risk factors for respiratory symptoms and chronic pulmonary disease in the current era.

HIV is associated with airway obstruction: a matched controlled study

OBJECTIVE

To explore whether airway obstruction is associated with HIV in a cohort of HIV-infected and uninfected smokers.

METHODS

People living with HIV (PLWHIV) participated in the ANRS EP48 HIV CHEST study, an early lung cancer diagnosis study with low-dose chest tomography. HIV-uninfected study participants were from the CONSTANCES cohort. Inclusion criteria were an age greater than 40 years, a smoking history of at least 20 pack-years, and for PLWHIV, a CD4 T-lymphocyte nadir less than 350/μl and last CD4 cell count more than 100 cells/μl. Two randomly selected HIV-uninfected study participants were matched by age and sex with one PLWHIV. Prebronchodilatator forced expiratory volume in 1 s (FEV1) to forced vital capacity (FVC) ratio was the primary outcome, and association of FEV1/FVC ratio less than 0.70 and FEV1 less than 80% of the theoretical value, as a proxy of chronic obstructive pulmonary disease, the secondary outcome.

RESULTS

In total, 351 PLWHIV and 702 HIV-uninfected study participants were included. Median age was 50 years, and 17% of study participants were women. Plasma HIV RNA was less than 50 copies/ml in 89% of PLWHIV, with a median CD4 cell count of 573 cells/μl. HIV (β -2.19), age (per 10 years increase; β -2.81), tobacco use (per 5 pack-years increase; β -0.34), and hepatitis C virus serology (β-2.50) were negatively associated with FEV1/FVC. HIV [odds ratio (OR: 1.72)], age (per 10 years increase; OR 1.77), and tobacco use (per 5 pack-years increase; OR 1.11) were significantly associated with the secondary outcome.

CONCLUSION

Our study found a significant association of airway obstruction with HIV status in smokers aged more than 40 years with previous immunodeficiency.

Airflow limitation in people living with HIV and matched uninfected controls

Introduction

Whether HIV influences pulmonary function remains controversial. We assessed dynamic pulmonary function in people living with HIV (PLWHIV) and uninfected controls.

Methods

A total of 1098 PLWHIV from the Copenhagen Co-morbidity in HIV infection study and 12 161 age-matched and sex-matched controls from the Copenhagen General Population Study were included. Lung function was assessed using FEV1 and FVC, while airflow limitation was defined by the lower limit of normal (LLN) of FEV1/FVC and by FEV1/FVC<0.7 with FEV1predicted <80% (fixed). Logistic and linear regression models were used to determine the association between HIV and pulmonary function adjusting for potential confounders (including smoking and socioeconomic status).

Results

In predominantly white men with mean (SD) age of 50.6 (11.1) the prevalence of airflow limitation (LLN) was 10.6% (95% CI 8.9% to 12.6%) in PLWHIV and 10.6% (95% CI 10.0 to 11.1) in uninfected controls. The multivariable adjusted OR for airflow limitation defined by LLN for HIV was 0.97 (0.77–1.21, P<0.78) and 1.71 (1.34–2.16, P<0.0001) when defined by the fixed criteria. We found no evidence of interaction between HIV and cumulative smoking in these models (P interaction: 0.25 and 0.17 for LLN and fixed criteria, respectively). HIV was independently associated with 197 mL (152–242, P<0.0001) lower FEV1 and 395 mL (344–447, P<0.0001) lower FVC, and 100 cells/mm3 lower CD4 nadir was associated with 30 mL (7–52, P<0.01) lower FEV1 and 51 mL (24–78, P<0.001) lower FVC.

Conclusion

HIV is a risk factor for concurrently decreased FEV1 and FVC. This excess risk is not explained by smoking or socioeconomic status and may be mediated by prior immunodeficiency.

Trial registration number

NCT02382822.

Prevalence of chronic obstructive pulmonary disease in the global population with HIV: a systematic review and meta-analysis

BACKGROUND

In recent years, the concept has been raised that people with HIV are at risk of developing chronic obstructive pulmonary disease (COPD) because of HIV infection. However, much remains to be understood about the relationship between COPD and HIV infection. We aimed to investigate this association by assessing studies that reported the prevalence of COPD in the global population with HIV.

METHODS

In this systematic review and meta-analysis, we assessed observational studies of COPD in people with HIV. We searched PubMed, Embase, Web of Science, and Global Index Medicus, with no language restriction, to identify articles published until June 21, 2017, and we searched the reference lists of the retrieved articles. Eligible studies reported the prevalence of COPD or had enough data to compute these estimates. We excluded studies in subgroups of participants selected on the basis of the presence of COPD; studies that were limited to other specific groups or populations, such as people with other chronic respiratory diseases; and case series, letters, reviews, commentaries, editorials, and studies without primary data or an explicit description of methods. The main outcome assessed was prevalence of COPD. Each study was independently reviewed for methodological quality. We used a random-effects model to pool individual studies and assessed heterogeneity (I²) using the χ² test on Cochrane's Q statistic. This study is registered with PROSPERO, number CRD42016052639.

FINDINGS

Of 4036 studies identified, we included 30 studies (151 686 participants) from all WHO regions in the meta-analysis of COPD prevalence. 23 studies (77%) had low risk of bias, six (20%) had moderate risk of bias, and one (3%) had high risk of bias in their methodological quality. The overall prevalence of COPD was 10·5% (95% CI 6·2-15·7; I²=97·2%; six studies) according to the lower limit of normal definition of COPD, and 10·6% (6·9-15·0; 94·7%; 16 studies) according to the fixed-ratio definition. COPD prevalence was higher in Europe and among current and ever smokers, and increased with level of income and proportion of participants with detectable HIV viral load. Prevalence of COPD was significantly higher in patients with HIV than in HIV-negative controls (pooled odds ratio 1·14, 95% CI 1·05-1·25, I²=63·5%; 11 studies), even after adjustment for tobacco consumption (2·58, 1·05-6·35, 74·9%; four studies).

INTERPRETATION

Our findings suggest a high prevalence of COPD in the global population with HIV, and an association with HIV. As such, COPD deserves more attention from HIV health-care providers, researchers, policy makers, and stakeholders for improved detection, overall proper management, and efficient control of COPD in people with HIV. Efforts to address this burden should focus on promoting the decrease of tobacco consumption and adherence to highly active antiretroviral therapy to reduce viral load.

FUNDING

None.