Incidence of bacterial respiratory infection and pneumonia in people with HIV with and without airflow limitation

OBJECTIVES

We aimed to determine the incidence rate, pathogen composition, and risk factors, particularly airflow limitation, associated with bacterial respiratory infection and pneumonia in a prospective cohort of well-treated people with HIV (PWH) between 2015-2021.

METHODS

We included 1007 PWH from the Copenhagen Comorbidity in HIV infection (COCOMO) study. Spirometry was performed at inclusion. Microbiology samples were collected prospectively. Cumulative incidence was determined by the Aalen-Johansen estimator. Cox proportional hazard models were used to calculate risk factors, adjusted for traditional and HIV-specific variables.

RESULTS

The incidence rates of first bacterial respiratory infection and pneumonia were 12.4 (95% CI 9.7-15.5) and 5.5 (95% CI: 3.8-7.7) per 1000 person-years, respectively. The cumulative incidence of pneumonia was four times higher in PWH with airflow limitation (11.8% vs 3.2%, P <0.001). Risk factors for bacterial respiratory infection were airflow limitation (hazard ratio [HR] 2.9, [95% CI: 1.7-5.1], P <0.001), smoking (HR 2.3, [95% CI: 1.4-3.8], P <0.001), and previous AIDS-defining event (HR 2.0, [95% CI: 1.2-3.3], P = 0.009). For pneumonia, airflow limitation (HR 2.7, [95% CI: 1.2-6.3], P = 0.016), smoking (HR 2.5, [95% CI: 1.2-5.4], P = 0.016), and older age (HR 1.5, [95% CI: 1.1-2.1], P = 0.015) were identified as risk factors.

CONCLUSIONS

Increased emphasis on airflow limitation prevention, including smoking cessation, may reduce the burden of bacterial respiratory infection and pneumonia in PWH.

Elevated Levels of Interleukin-1β and Interleukin-10 Are Associated With Faster Lung Function Decline in People With Well-Treated Human Immunodeficiency Virus

BACKGROUND

People with human immunodeficiency virus (PWH) have an increased risk of chronic lung diseases and chronic inflammation. We aimed to investigate if inflammatory markers and monocyte activation are associated with faster lung function decline in PWH.

METHODS

We included 655 PWH from the Copenhagen Comorbidity in HIV Infection (COCOMO) Study. Eligible participants were aged ≥25 years and had 2 spirometries separated by >2 years. Inflammatory markers (interleukin [IL]-1β, IL-2, IL-6, IL-10, tumor necrosis factor-α, and interferon-γ) were measured at baseline by Luminex, and soluble CD14 and soluble CD163 by enzyme-linked immunosorbent assay. Using linear mixed models, we investigated whether elevated cytokine levels were associated with faster lung function decline.

RESULTS

The majority of PWH were males (85.2%) with undetectable viral replication (95.3%). We found a faster decline in forced expiratory volume in 1 second (FEV1) in PWH with elevated IL-1β and IL-10, with an additional decline of 10.3 mL/year (95% confidence interval [CI], 2.1-18.6; P = .014) and 10.0 mL/year (95% CI, 1.8-18.2; P = .017), respectively. We found no interaction between smoking and IL-1β or IL-10 on FEV1 decline.

CONCLUSIONS

Elevated IL-1β and IL-10 were independently associated with faster lung function decline in PWH, suggesting that dysregulated systemic inflammation may play a role in the pathogenesis of chronic lung diseases.

Pulmonary function tests and their associated factors in people living with HIV at Jimma medical center; Ethiopia: a comparative cross-sectional study

Background

People living with HIV (PLHIV) have a greater risk of developing respiratory disorders. The problems are linked to poor socio-economic status, high viral load, low CD4 counts, and antiretroviral therapy. Despite the high prevalence of respiratory disorders, the association between HIV infection and pulmonary function status, as well as the associated factors, is not well established in resource-limited countries.

Methods

A comparative cross-sectional study was conducted from September 24 to October 15 2020 at Jimma Medical Center among people living with HIV who were arranged into an age-sex-matched comparison group. Data were collected using a pretested structured questionnaire administered via face-to-face interviews. The collected data included socio-demographic, respiratory, HIV infection, and substance use variables. Pulmonary function tests were conducted using an SP10 spirometer. The collected data were entered and analyzed using SPSS version 26. Independent t-test and multiple linear regressions were carried out to identify factors associated with the pulmonary function status of the study participants.

Results

A total of 96 PLHIV and 96 matched control individuals participated in the study. The mean of pulmonary function test parameters among the PLHIV respondents was FVC (l) (67.35 ± 19.12, p0.003), FEV1s (l) (61.76 ± 16.04, p0.001), and PEFR (50.14 ± 23.32, p0.001), with a significant lowering in the study group. Female sex, respiratory symptoms, duration of HIV, duration of treatment, and khat chewing were associated with lowered FEV1s (l) (p < 0.05) in HIV-positive respondents.

Conclusion

PLHIV had significantly lower mean lung function parameters than HIV-uninfected participants. As a result, health providers should screen HIV-positive patients with respiratory symptoms, prolonged duration of HIV infection, prolonged treatment, and khat chewing for non-infectious lung disorders while treating them.

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.

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.

Interstitial Lung Abnormalities in People With HIV Infection and Uninfected Controls

BACKGROUND

Chest computed tomography (CT) findings in well-treated people with HIV infection (PWH) remain poorly characterized.

METHODS

Cross-sectional analysis examining interstitial chest CT findings in PWH (n = 754) and uninfected controls (n = 470).

RESULTS

HIV infection was independently associated with 1.82 (95% CI, 1.18-2.88) and 5.15 (95% CI, 1.72-22.2) higher adjusted odds of any interstitial lung abnormality and findings suspicious for interstitial lung disease, respectively.

CONCLUSIONS

HIV infection was independently associated with interstitial lung abnormalities and findings suspicious for interstitial lung disease. Whether these abnormalities develop into more recognizable disease states over time is unknown but warrants further investigation.

Association of Lung Function With HIV-Related Quality of Life and Health Care Utilization in a High-Risk Cohort

BACKGROUND

Chronic respiratory disease represents an important comorbidity for persons living with HIV (PLWH). HIV itself is associated with greater impairment in lung function. We aimed to determine the association between declining lung function and both quality of life (QOL) and health care utilization for PLWH.

METHODS

Using longitudinal data from the Study of HIV Infection in the Etiology of Lung Disease 2009-2017, we studied the association between changes in lung function and both QOL and acute care events (emergency department visit or hospitalization). The Medical Outcomes Studies-HIV Questionnaire provided QOL domains. Multivariable regression models were performed with generalized estimating equations accounting for 1499 participants, 485 with HIV, contributing 10,825 spirometry visits.

RESULTS

Among PLWH, decreased FEV1 was associated with worse physical health for those with higher viral load [β: -1.66, 95% confidence interval (CI): -3.11 to -0.39] compared to those with viral suppression (β: -0.58, 95% CI: -1.06 to -0.162), even in those without airflow obstruction. Lower FEV1 was also associated with increased odds of both emergency department (odds ratio: 1.21, 95% CI: 1.09 to 1.34) and inpatient (odds ratio: 1.26, 95% CI: 1.12 to 1.42) hospitalizations for PLWH. Lung function was not associated with increased odds of acute care events for HIV-uninfected participants.

CONCLUSIONS

FEV1 declines represent an independent predictor of QOL and acute care events among PLWH. Although the generalizability of these results may be limited, because of the high-risk population included, findings suggest that care for PLWH should involve monitoring FEV1 over time, especially in those with poor virologic control, with emphasis on the development and implementation of interventions to mitigate lung function decline.

Pathogenesis of HIV-Related Lung Disease: Immunity, Infection, and Inflammation

Despite anti-retroviral therapy (ART), human immunodeficiency virus-1 (HIV)-related pulmonary disease continues to be a major cause of morbidity and mortality for people living with HIV (PLWH). The spectrum of lung diseases has changed from acute opportunistic infections resulting in death to chronic lung diseases for those with access to ART. Chronic immune activation and suppression can result in impairment of innate immunity and progressive loss of T cell and B cell functionality with aberrant cytokine and chemokine responses systemically as well as in the lung. HIV can be detected in the lungs of PLWH and has profound effects on cellular immune functions. In addition, HIV-related lung injury and disease can occur secondary to a number of mechanisms including altered pulmonary and systemic inflammatory pathways, viral persistence in the lung, oxidative stress with additive effects of smoke exposure, microbial translocation, and alterations in the lung and gut microbiome. Although ART has had profound effects on systemic viral suppression in HIV, the impact of ART on lung immunology still needs to be fully elucidated. Understanding of the mechanisms by which HIV-related lung diseases continue to occur is critical to the development of new preventive and therapeutic strategies to improve lung health in 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.