Association between inhibitors of the renin-angiotensin system and lung function in elderly patients recovered from severe COVID-19

Proteomic analysis of lung responses to SARS-CoV-2 infection in aged non-human primates: clinical and research relevance

With devastating health and socioeconomic impact worldwide, much work is left to understand the Coronavirus Disease 2019 (COVID-19), with emphasis in the severely affected elderly population. Here, we present a proteomics study of lung tissue obtained from aged vs. young rhesus macaques (Macaca mulatta) and olive baboons (Papio Anubis) infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Using age as a variable, we identified common proteomic profiles in the lungs of aged infected non-human primates (NHPs), including key regulators of immune function, as well as cell and tissue remodeling, and discuss the potential clinical relevance of such parameters. Further, we identified key differences in proteomic profiles between both NHP species, and compared those to what is known about SARS-CoV-2 in humans. Finally, we explored the translatability of these animal models in the context of aging and the human presentation of the COVID-19.

Block of the Angiotensin Pathways Affects Flow-Volume Spirometry in Patients with SARS-CoV-2 Infection

BACKGROUND

Angiotensin Converting Enzyme 2 (ACE2) is an endothelial cell receptor used by SARS-CoV- 2 virus to enter cells. Pulmonary function tests (PFTs), mainly spirometry, are the main diagnostic tools for most respiratory diseases. PFTs are mandatory for assessing the response to therapy.

AIM

We evaluated patients after the SARS-CoV-2 infection through flow-volume spirometry that evaluates the role of drugs inhibiting the ACE2 pathway.

MATERIAL AND METHODS

We evaluated 112 Caucasian patients 3-6 months after COVID-19 disease, i.e. after the date of negative molecular or antigenic nasopharyngeal swab. The series of patients showed a great variability due to a wide spectrum of age, the severity of disease manifestations, hospitalization, invasive/non-invasive ventilation, comorbidities, the presence/absence of a previous pneumological diagnosis and the variants of the virus. Patients were divided into those who were being treated with angiotensin receptor blocker (ARB) or ACE2 inhibitors (ACEi) (ARB/ACEi, group 1, 23 females and 12 males, aged 63.63 ± 10.40), and those who were not treated with these drugs (group 2, 38 females and 37 males, aged 55.12 ± 16.51). Distal airflow obstruction (DAO) was evaluate as forced expiratory flow (FEF) at 25%, 50% and 75% of total flow.

RESULTS

Group 1 presented lower peripheral oxygen saturation percentage vs group 2 (96.54 ± 3.06 vs 97.30 ± 1.19%, p < 0.05). Spirometry data were worst in group1: Forced expiratory volume at first minute (FEV1) (91.20 ± 17.09 vs 97.56 ± 16.40%, p < 0.05), Forced vital capacity (94.06 ± 17.48 vs 99.13 ± 17.71%, p < 0.05), and Tiffenau Index (0.78 ± 0.12 vs 0.84 ± 0.10, p < 0.05). There was a DAO in group1. In group 1, we found also a reduction in FEF 25 (73.97 ± 27.28 vs 86.89 ± 22.44%, p < 0.05), FEF 50 (74.69 ± 33.01 vs 85.67 ± 23.74%, p < 0.05), and FEF 25-75 (74.14 ± 35.03 vs 83.92 ± 25.38%, p < 0.05) but not in FEF 75 (73.06 ± 39.37 vs 82.27 ± 43.33%, p < 0.05).

DISCUSSION

In patients treated with ARB/ACEi the indexes of respiratory function were shifted towards the lower limits (albeit within normal limits). These parameters were significantly reduced compared to patients not treated with these drugs. This indicates that the COVID-19 disease is not only a pulmonary disease, but also a vascular one.

Beta receptor blocker therapy for the elderly in the COVID-19 era

When the coronavirus disease 2019 (COVID-19) pandemic spread globally from the Hubei region of China in December 2019, the impact on elderly people was particularly unfavorable. The mortality associated with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection was highest in older individuals, in whom frailty and comorbidities increased susceptibility to severe forms of COVID-19. Unfortunately, in older patients, the course of COVID-19 was often characterized by significant cardiovascular complications, such as heart failure decompensation, arrhythmias, pericarditis, and myopericarditis. Ensuring that the elderly have adequate therapeutic coverage against known cardiovascular diseases and risk factors is particularly important in the COVID-19 era. Beta blockers are widely used for the treatment and prevention of cardiovascular disease. The clinical benefits of beta blockers have been confirmed in elderly patients, and in addition to their negative chronotropic effect, sympathetic inhibition and anti-inflammatory activity are theoretically of great benefit for the treatment of COVID-19 infection. Beta blockers have not been clearly shown to prevent SARS-CoV-2 infection, but there is evidence from published studies including elderly patients that beta blockers are associated with a more favorable clinical course of COVID-19 and reduced mortality. In this minireview, we summarize the most important evidence available in the literature on the usefulness of beta blocker therapy for older patients in the context of the COVID-19 pandemic.

Risk factors for impaired pulmonary diffusion function in convalescent COVID-19 patients: A systematic review and meta-analysis

BACKGROUND

The long-term prognosis of COVID-19 survivors remains poorly understood. It is evidenced that the lung is the main damaged organ in COVID-19 survivors, most notably in impairment of pulmonary diffusion function. Hence, we conducted a meta-analysis of the potential risk factors for impaired diffusing capacity for carbon monoxide (DLCO) in convalescent COVID-19 patients.

METHODS

We performed a systematic search of PubMed, Web of Science, Embase, and Ovid databases for relevant studies from inception until January 7, 2022, limited to papers involving human subjects. Studies were reviewed for methodological quality. Fix-effects and random-effects models were used to pool results. Heterogeneity was assessed using I². The publication bias was assessed using the Egger's test. PROSPERO registration: CRD42021265377.

FINDINGS

A total of eighteen qualified articles were identified and included in the systematic review, and twelve studies were included in the meta-analysis. Our results showed that female (OR: 4.011; 95% CI: 2.928-5.495), altered chest computerized tomography (CT) (OR: 3.002; 95% CI: 1.319-6.835), age (OR: 1.018; 95% CI: 1.007-1.030), higher D-dimer levels (OR: 1.012; 95% CI: 1.001-1.023) and urea nitrogen (OR: 1.004;95% CI: 1.002-1.007) were identified as risk factors for impaired DLCO.

INTERPRETATION

Pulmonary diffusion capacity was the most common impaired lung function in recovered patients with COVID-19. Several risk factors, such as female, altered chest CT, older age, higher D-dimer levels and urea nitrogen are associated with impairment of DLCO. Raising awareness and implementing interventions for possible modifiable risk factors may be valuable for pulmonary rehabilitation.

FUNDING

This work was financially supported by Emergency Key Program of Guangzhou Laboratory (EKPG21-29, EKPG21-31), Incubation Program of National Science Foundation for Distinguished Young Scholars by Guangzhou Medical University (GMU2020-207).