Reduced carbon monoxide transfer factor (TLCO) in human immunodeficiency virus type I (HIV-I) infection as a predictor for faster progression to AIDS

Pulmonary Function in HIV-Infected Children at a Tertiary Care Hospital in North India: A Prospective Cross-Sectional Study

Background The global burden of HIV remains significant, particularly in India. Antiretroviral therapy (ART) has improved outcomes for children with HIV, yet understanding the virus's impact on respiratory health is essential. Pulmonary complications, common in HIV-infected adults, are poorly understood in children. Despite India's high HIV prevalence, data on pediatric lung function are lacking. This study aims to evaluate spirometry-based pulmonary function in perinatally HIV-infected children, exploring associations with disease severity, immune status, and other factors. Methods This prospective cross-sectional study conducted in a North Indian tertiary care hospital aimed to assess pulmonary function using spirometry in children (6-18 years) with HIV infection. Ethical approval and informed consent were secured. Data on demographics, clinical history, CD4+ T-cell counts, and viral load were collected. Certified respiratory therapists performed spirometry using standardized protocols. Descriptive statistics were computed, and differences in pulmonary function based on CD4+ T-cell counts, viral load, and opportunistic infection were analyzed. The study adhered to ethical guidelines and maintained participants' confidentiality. Results This cross-sectional study enrolled 57 children (mean age 13.6±3.2 years) with HIV infection. Age distribution was <9 years (24.6%), 9-11 years (28.1%), and >11 years (47.4%). Males constituted 56.1%. The mean BMI was 15.92±2.78 kg/m². HIV viral load (87.23±56.28 copies/μL) and CD4 count (1146.32±103.98 cells/mm³) were recorded. ART duration averaged 6.21±1.36 years. Viral load groups were <1 (52.6%), 1-1000 (26.3%), and >1000 copies/μL (21.1%). CD4 categories were >500 cells/mm³ (47.4%), 200-499 (42.1%), and <200 cells/mm³ (10.5%). Spirometry showed 71.9% normal and 28.1% abnormal (mild/moderate obstruction: 18.8%, mild/moderate restriction: 81.3%). No significant spirometric differences were observed among CD4 or viral load groups (p>0.05), nor with opportunistic infections (p>0.05). Conclusion This study reveals complex associations between spirometric parameters and CD4 count, viral load, and opportunistic infections in children with HIV. Further research, including longitudinal studies, is needed to unravel the intricate interplay and improve management strategies for this population.

Pathogenesis and management of emphysema in people with HIV

INTRODUCTION

Since early in the HIV epidemic, emphysema has been identified among people with HIV (PWH) and has been associated with increased mortality. Smoking cessation is key to risk reduction. Health maintenance for PWH and emphysema should ensure appropriate vaccination and lung cancer screening. Treatment should adhere to inhaler guidelines for the general population, but inhaled corticosteroid (ICS) should be used with caution. Frontiers in treatment include targeted therapeutics. Major knowledge gaps exist in the epidemiology of and optimal care for PWH and emphysema, particularly in low and middle-income countries (LMIC).

AREAS COVERED

Topics addressed include risk factors, pathogenesis, current treatment and prevention strategies, and frontiers in research.

EXPERT OPINION

There are limited data on the epidemiology of emphysema in LMIC, where more than 90% of deaths from COPD occur and where the morbidity of HIV is most heavily concentrated. The population of PWH is aging, and age-related co-morbidities such as emphysema will only increase in salience. Over the next 5 years, the authors anticipate novel trials of targeted therapy for emphysema specific to PWH, and we anticipate a growing body of evidence to inform optimal clinical care for lung health among PWH in LMIC.

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.

Increasing burden of noninfectious lung disease in persons living with HIV: a 7-year study using the French nationwide hospital administrative database

An overall reduction in the incidence of AIDS and a change in the spectrum of lung disease have been noticed in persons living with HIV (PLHIV). Our aim was to provide an epidemiological update regarding the prevalence of lung diseases in PLHIV hospitalised in France.We analysed the prevalence of lung disease in PLHIV hospitalised in France from 2007 to 2013, from the French nationwide hospital medical information database, and assessed the association between HIV and incident noninfectious disease over 4 years of follow-up.A total of 52 091 PLHIV were hospitalised in France between 2007 and 2013. Among PLHIV hospitalised with lung disease, noninfectious lung diseases increased significantly from 45.6% to 54.7% between 2007 and 2013, whereas the proportion of patients with at least one infectious lung disease decreased significantly. In 2010, 10 067 prevalent hospitalised PLHIV were compared with 8 244 682 hospitalised non-PLHIV. In 30-49-year-old patients, HIV infection was associated with chronic obstructive pulmonary disease (COPD), chronic respiratory failure, emphysema, lung fibrosis and pulmonary arterial hypertension (PAH) even after adjustment for smoking.The emergence of noninfectious lung disease, in particular COPD, emphysema, lung fibrosis, PAH and chronic respiratory disease, in PLHIV would justify mass screening in this population.

Non-infectious pulmonary disorders in HIV

INTRODUCTION

Since the advent of antiretroviral therapy (ART), non-infectious pulmonary disorders have become common comorbidities in the human immunodeficiency virus (HIV) positive population. Clinicians caring for those with HIV disease should be aware of the prevalence of non-infectious pulmonary disorders. A comprehensive understanding is required to diagnosis and manage these syndromes appropriately. Areas covered: This review focuses on the epidemiology, risk factors, pathogenesis, clinical feature and diagnosis, and treatment of HIV-related chronic obstructive pulmonary disease (COPD), lung cancer, pulmonary hypertension. Expert Commentary: The prevalence of COPD in the HIV population is frequent and requires appropriate diagnosis and treatment. HIV-positive individuals with lung cancer carry a poorer prognosis and require early diagnosis and treatment. A complex condition exists with pulmonary hypertension in the HIV population and requires a high degree of clinical suspicion for early diagnosis.

HIV-associated obstructive lung diseases: insights and implications for the clinician

The effectiveness of antiretroviral therapy to control HIV infection has led to the emergence of an older HIV population who are at risk of chronic diseases. Through a comprehensive search of major databases, this Review summarises information about the associations between chronic obstructive pulmonary disease (COPD), asthma, and HIV infection. Asthma and COPD are more prevalent in HIV-infected populations; 16-20% of individuals with HIV infection have asthma or COPD, and poorly controlled HIV infection worsens spirometric and diffusing capacity measurements, and accelerates lung function decline by about 55-75 mL/year. Up to 21% of HIV-infected individuals have obstructive ventilatory defects and reduced diffusing capacity is seen in more than 50% of HIV-infected populations. Specific pharmacotherapy considerations are needed to care for HIV-infected populations with asthma or COPD-protease inhibitor regimens to treat HIV (such as ritonavir) can result in systemic accumulation of inhaled corticosteroids and might increase pneumonia risk, exacerbating the toxicity of this therapy. Therefore, it is essential for clinicians to have a heightened awareness of the increased risk and manifestations of obstructive lung diseases in HIV-infected patients and specific therapeutic considerations to care for this population. Screening spirometry and tests of diffusing capacity might be beneficial in HIV-infected people with a history of smoking or respiratory symptoms.

Contributors to diffusion impairment in HIV-infected persons

Abnormal diffusing capacity is common in HIV-infected individuals, including never smokers. Aetiologies for diffusing capacity impairment in HIV are not understood, particularly in those without a history of cigarette smoking. Our study was a cross-sectional analysis of 158 HIV-infected individuals without acute respiratory symptoms or infection with the aim to determine associations between a diffusing capacity of the lung for carbon monoxide (D(LCO)) % predicted and participant demographics, pulmonary spirometric measures (forced expiratory volume in 1 s (FEV1) and FEV1/forced vital capacity), radiographic emphysema (fraction of lung voxels < -950 Hounsfield units), pulmonary vascular/cardiovascular disease (echocardiographic tricuspid regurgitant jet velocity, N-terminal pro-brain natriuretic peptide) and airway inflammation (induced sputum cell counts), stratified by history of smoking. The mean D(LCO) was 65.9% predicted, and 55 (34.8%) participants had a significantly reduced D(LCO) (<60% predicted). Lower D(LCO) % predicted in ever-smokers was associated with lower post-bronchodilator FEV1 % predicted (p<0.001) and greater radiographic emphysema (p=0.001). In never-smokers, mean±SD D(LCO) was 72.7±13.4% predicted, and D(LCO) correlated with post-bronchodilator FEV1 (p=0.02), sputum neutrophils (p=0.03) and sputum lymphocytes (p=0.009), but not radiographic emphysema. Airway obstruction, emphysema and inflammation influence D(LCO) in HIV. Never-smokers may have a unique phenotype of diffusing capacity impairment. The interaction of multiple factors may account for the pervasive nature of diffusing capacity impairment in HIV infection.

Human immunodeficiency virus-associated obstructive lung diseases

In the era of effective antiretroviral therapy (ART), epidemiologic studies have found that persons infected with human immunodeficiency virus (HIV) have a higher prevalence and incidence of chronic obstructive pulmonary disease than HIV-uninfected persons. In comparison with HIV-uninfected persons and those with well-controlled HIV disease, HIV-infected persons with poor viral control or lower CD4 cell count have more airflow obstruction, a greater decline in lung function, and possibly more severe diffusing impairment. This article reviews the evidence linking HIV infection to obstructive lung disease, and discusses management issues related to the treatment of obstructive lung disease in HIV-infected patients.

Cigarette smoking in the HIV-infected population

As mortality due to AIDS-related causes has decreased with the use of antiretroviral therapy, there has been a rise in deaths related to non-AIDS-defining illnesses. Given the exceedingly high prevalence of cigarette smoking among individuals living with HIV infection, tobacco has been implicated as a major contributor to this paradigm shift. Evidence suggests that smoking-related illnesses, such as cardiovascular disease, respiratory illnesses, and certain malignancies, contribute substantially to morbidity and mortality among HIV-infected persons. In this review, we summarize the adverse health consequences of smoking relevant to HIV-infected individuals and discuss smoking cessation in this unique population, including a discussion of barriers to quitting and a review of studies that have examined smoking cessation interventions.

Interactions between HIV infection and chronic obstructive pulmonary disease: Clinical and epidemiological aspects

Introduction

An association between HIV infection and chronic obstructive pulmonary disease (COPD) has been observed in several studies.

Objective and methods

we conducted a review of the literature linking HIV infection to COPD, focusing on clinical and epidemiological data published before and during widespread highly active antiretroviral therapy (HAART).

Results

Interactions between HIV infection and COPD appear to be influenced by multiple factors. In particular, the bronchopulmonary tract can be damaged by HIV infection, the immunodeficiency it induces, and the resulting increase in the risk of pulmonary infections. In addition, the prevalence of smoking and intravenous drug use is higher in HIV-infected populations, also increasing the risk of COPD. Before the advent of HAART, respiratory tract infections probably played a major role. Since the late 1990s and the widespread use of HAART, the frequency of opportunistic infections has fallen but new complications have emerged as life expectancy has increased.

Conclusion

given the high prevalence of smoking among HIV-infected patients, COPD may contribute significantly to morbidity and mortality in this setting.

Pulmonary function abnormalities in HIV-infected patients during the current antiretroviral therapy era

RATIONALE

Before the introduction of combination antiretroviral (ARV) therapy, patients infected with HIV had an increased prevalence of respiratory symptoms and lung function abnormalities. The prevalence and exact phenotype of pulmonary abnormalities in the current era are unknown. In addition, these abnormalities may be underdiagnosed.

OBJECTIVES

Our objective was to determine the current burden of respiratory symptoms, pulmonary function abnormalities, and associated risk factors in individuals infected with HIV.

METHODS

Cross-sectional analysis of 167 participants infected with HIV who underwent pulmonary function testing.

MEASUREMENTS AND MAIN RESULTS

Respiratory symptoms were present in 47.3% of participants and associated with intravenous drug use (odds ratio [OR] 3.64; 95% confidence interval [CI], 1.32-10.046; P = 0.01). Only 15% had previous pulmonary testing. Pulmonary function abnormalities were common with 64.1% of participants having diffusion impairment and 21% having irreversible airway obstruction. Diffusion impairment was independently associated with ever smoking (OR 2.46; 95% CI, 1.16-5.21; P = 0.02) and Pneumocystis pneumonia prophylaxis (OR 2.94; 95% CI, 1.10-7.86; P = 0.01), whereas irreversible airway obstruction was independently associated with pack-years smoked (OR 1.03 per pack-year; 95% CI, 1.01-1.05; P < 0.01), intravenous drug use (OR 2.87; 95% CI, 1.15-7.09; P = 0.02), and the use of ARV therapy (OR 6.22; 95% CI, 1.19-32.43; P = 0.03).

CONCLUSIONS

Respiratory symptoms and pulmonary function abnormalities remain common in individuals infected with HIV. Smoking and intravenous drug use are still important risk factors for pulmonary abnormalities, but ARV may be a novel risk factor for irreversible airway obstruction. Obstructive lung disease is likely underdiagnosed in this population.

The pathophysiology of pulmonary diffusion impairment in human immunodeficiency virus infection

Numerous reports have demonstrated that prior to the development of acquired immunodeficiency syndrome (AIDS)-related pulmonary complications, human immunodeficiency virus-positive (HIV+) individuals commonly develop unexplained reductions in pulmonary diffusing capacity (DLCO). The potential relevance of this observation is underscored by recent data demonstrating that reductions in DLCO independently predict the subsequent development of opportunistic pneumonia. To delineate the alterations in gas exchange associated with HIV, we investigated a group of HIV+ subjects with unexplained reductions in DLCO, using high-resolution computed tomography (HRCT) of the chest and a separation of diffusing capacity into its membrane (Dm) and capillary blood volume (Vc) components. We compared this abnormal group with HIV+ subjects with more normal gas exchange and also with a group of HIV- volunteers matched for age and smoking history. Compared with other groups, the HIV+ group with diffusion impairment demonstrated prominent reductions in Vc, despite a well-preserved total lung capacity (TLC). HRCT demonstrated virtually no evidence of interstitial fibrosis in any HIV+ subject, but evidence of early emphysema that significantly correlated with DLCO. Our results suggest that the previously reported impairment in pulmonary gas exchange in the HIV+ population involves loss of Vc and likely represents the development of early emphysema.

Effects of smoking and clinical status on lung function in human immunodeficiency virus (HIV)-seropositive subjects

Lung function was measured at 3-month intervals for up to 1 yr in a group of Caucasian HIV-seropositive subjects. The objective was to document any deterioration in lung function and seek correlations between such deterioration and smoking history and Centers for Disease Control (CDC) status. Ninety-nine subjects were studied at enrollment; 43 were followed-up (mean duration 9 +/- 3 months). Ninety-five of the 99 enrolled subjects remained free of HIV-related respiratory disease and were included in the analysis. At enrollment, carbon monoxide diffusing capacity (TLCO) was significantly lower than predicted in non-smokers, smokers and ex-smokers (88, 77 and 88%, respectively, P < 0.001). The TLCO measurements in the smoking group were significantly lower than those of the life-long non-smoking subjects (P < 0.01). Residual volume (RV) was significantly higher than predicted in smokers (111%, P = 0.02). During follow-up, all three groups demonstrated significant declines in TLCO (7%, P = 0.01; 9%, P = 0.005; 13%, P < 0.001, respectively), and increases in RV (9%, P = 0.03; 13.5%, P = 0.02, 22%, P = 0.02, respectively). At enrollment, significantly lower than predicted values of TLCO were observed in groups stratified by CDC criteria: in asymptomatic HIV-seropositive subjects (CDC 11) 89%, P = 0.01; persistent generalized lymphadenopathy (PGL) 84%; AIDS-related complex (ARC) 81%; and in non-pulmonary AIDS (IV C1) 69%, P = 0.0001, respectively. Residual volume was significantly higher than predicted in CDC II (114%, P = 0.05). During follow-up, TLCO fell in groups PGL and ARC by 7 and 9%, respectively, while RV increased in groups CDC II, PGL and ARC by 17, 15 and 8%, respectively. Only the TLCO decline in PGL showed any linkage to clinical deterioration. This study demonstrates deficits at enrollment, and a continuing decline of TLCO and increase in RV in HIV-seropositive subjects without overt lung disease.

Immunologic effects of HIV in the lung

This article covers a selected group of topics dealing with the contribution of lung immunocompetent cells in the host defense mechanisms against HIV. These include recent findings suggesting that bidirectional signals between alveolar macrophages and pulmonary cytotoxic T lymphocytes define regulatory networks, which contribute to the accumulation of HIV-specific effector cells in the lung microenvironment. The authors also emphasize the cell pattern of HIV infection in the lung, highlighting the role of the retrovirus in weakening pulmonary host defenses and its spreading into the lower respiratory tract.