Who is lost to follow-up in HIV care? Assessment of care retention over time and the impact of COVID-19. Longitudinal analysis of the PISCIS cohort.

INTRODUCTION: People living with HIV who are lost to follow-up have a greater risk of health deterioration, mortality, and community transmission. OBJECTIVE: Our aim was to analyse both how rates of loss to follow-up (LTFU) changed between 2006 and 2020 and how the COVID-19 pandemic affected these rates in the PISCIS cohort study of Catalonia and the Balearic Islands. METHODS: We analysed socio-demographic and clinical characteristics of LTFU yearly and with adjusted odds ratios to assess the impact of these determinants on LTFU in 2020 (the year of COVID-19). We used latent class analysis to categorize classes of LTFU based on their socio-demographic and clinical characteristics at each year. RESULTS: In total, 16.7% of the cohort were lost to follow-up at any time in the 15 years (n = 19 417). Of people living with HIV who were receiving follow-up, 81.5% were male and 19.5% were female; of those who were lost to follow-up, 79.6% and 20.4% were male and female, respectively (p < 0.001). Although rates of LTFU increased during COVID-19 (1.11% vs. 0.86%, p = 0.024), socio-demographic and clinical factors were similar. Eight classes of people living with HIV who were lost to follow-up were identified: six for men and two for women. Classes of men (n = 3) differed in terms of their country of birth, viral load (VL), and antiretroviral therapy (ART); classes of people who inject drugs (n = 2) differed in terms of VL, AIDS diagnosis, and ART. Changes in rates of LTFU included higher CD4 cell count and undetectable VL. CONCLUSIONS: The socio-demographic and clinical characteristics of people living with HIV changed over time. Although the circumstances of the COVID-19 pandemic increased the rates of LTFU, the characteristics of these people were similar. Epidemiological trends among people who were lost to follow-up can be used to prevent new losses of care and to reduce barriers to achieve Joint United Nations Programme on HIV/AIDS 95-95-95 targets.

SARS-CoV-2 Vaccination Coverage and Factors Associated with Low Uptake in a Cohort of People Living with HIV.

People living with HIV (PLWH) are prioritised for SARS-CoV-2 vaccination due to their vulnerability to severe COVID-19. Therefore, the epidemiological surveillance of vaccination coverage and the timely identification of suboptimally vaccinated PLWH is vital. We assessed SARS-CoV-2 vaccination coverage and factors associated with under-vaccination among PLWH in Catalonia, Spain. As of 11.12.2021, 9945/14942 PLWH (66.6%) had received ≥1 dose of a SARS-CoV-2 vaccine. Non-Spanish origin (adjusted odds ratio (aOR) 0.64, 95% CI 0.59-0.70), CD4 count of 200-349 cells/µL (aOR 0.74, 95% CI 0.64-0.86) or 350-499 cells/µL (aOR 0.79, 95% CI 0.70-0.88), detectable plasma HIV-RNA (aOR 0.61 95% CI 0.53-0.70), and previous SARS-CoV-2 diagnosis (aOR 0.58 95% CI 0.51-0.65) were associated with under-vaccination. SARS-CoV-2 diagnosis (437 [9.5%] vs. 323 [3.5%], p < 0.001), associated hospitalisations (10 [2.3%] vs. 0 [0%], p < 0.001), intensive care unit admissions (6 [1.4%] vs. 0 [0%], p < 0.001), and deaths (10 [2.3%] vs. 0 [0%], p < 0.001) were higher among unvaccinated PLWH. Vaccination coverage was lower among PLWH with a CD4 count >200 cells/µL, detectable plasma HIV-RNA, previous SARS-CoV-2 diagnosis, and migrants. SARS-CoV-2 diagnosis, associated hospitalisations, and deaths among PLWH were lower among the vaccinated compared with the unvaccinated. SARS-CoV-2 vaccination prioritisation has not completely reached vulnerable PLWH with poorer prognosis. This information can be used to inform public health strategies.

Impact of tenofovir on SARS-CoV-2 infection and severe outcomes among people living with HIV: a propensity score-matched study.

BACKGROUND: Reports on the impact of some antiretrovirals against SARS-CoV-2 infection and disease severity are conflicting. OBJECTIVES: We evaluated the effect of tenofovir as either tenofovir alafenamide/emtricitabine (TAF/FTC) or tenofovir disoproxil fumarate/emtricitabine (TDF/FTC) against SARS-CoV-2 infection and associated clinical outcomes among people living with HIV (PLWH). METHODS: We conducted a propensity score-matched analysis in the prospective PISCIS cohort of PLWH (n = 14 978) in Catalonia, Spain. We used adjusted Cox regression models to assess the association between tenofovir and SARS-CoV-2 outcomes. RESULTS: After propensity score-matching, SARS-CoV-2 diagnosis rates were similar in TAF/FTC versus ABC/3TC recipients (11.6% versus 12.5%, P = 0.256); lower among TDF/FTC versus ABC/3TC recipients (9.6% versus 12.8%, P = 0.021); and lower among TDF/FTC versus TAF/FTC recipients (9.6% versus 12.1%, P = 0.012). In well-adjusted logistic regression models, TAF/FTC was no longer associated with reduced SARS-CoV-2 diagnosis [adjusted odds ratio (aOR) 0.90; 95% confidence interval (CI), 0.78-1.04] or hospitalization (aOR 0.93; 95% CI, 0.60-1.43). When compared with ABC/3TC, TDF/FTC was not associated with reduced SARS-CoV-2 diagnosis (aOR 0.79; 95% CI, 0.60-1.04) or hospitalization (aOR 0.51; 95% CI, 0.15-1.70). TDF/FTC was not associated with reduced SARS-CoV-2 diagnosis (aOR 0.79; 95% CI, 0.60-1.04) or associated hospitalization (aOR 0.33; 95% CI, 0.10-1.07) compared with TAF/FTC. CONCLUSIONS: TAF/FTC or TDF/FTC were not associated with reduced SARS-CoV-2 diagnosis rates or associated hospitalizations among PLWH. TDF/FTC users had baseline characteristics intrinsically associated with more benign SARS-CoV-2 infection outcomes. Tenofovir exposure should not modify any preventive or therapeutic SARS-CoV-2 infection management.

An ACE2/Mas-related receptor MrgE axis in dopaminergic neuron mitochondria.

ACE2 plays a pivotal role in the balance between the pro-oxidative pro-inflammatory and the anti-oxidative anti-inflammatory arms of the renin-angiotensin system. Furthermore, ACE2 is the entry receptor for SARS-CoV-2. Clarification of ACE2-related mechanisms is crucial for the understanding of COVID-19 and other oxidative stress and inflammation-related processes. In rat and monkey brain, we discovered that the intracellular ACE2 and its products Ang 1-7 and alamandine are highly concentrated in the mitochondria and bind to a new mitochondrial Mas-related receptor MrgE (MrgE) to produce nitric oxide. We found MrgE expressed in neurons and glia of rodents and primates in the substantia nigra and different brain regions. In the mitochondria, ACE2 and MrgE expressions decreased and NOX4 increased with aging. This new ACE2/MrgE/NO axis may play a major role in mitochondrial regulation of oxidative stress in neurons, and possibly other cells. Therefore, dysregulation of the mitochondrial ACE2/MrgE/NO axis may play a major role in neurodegenerative processes of dopaminergic neurons, where mitochondrial dysfunction and oxidative stress play a crucial role. Since ACE2 binds SARS-CoV-2 spike protein, the mitochondrial ACE2/MrgE/NO axis may also play a role in SARS-CoV-2 cellular effects.

Experimental data using candesartan and captopril indicate no double-edged sword effect in COVID-19.

The key link between renin-angiotensin system (RAS) and COVID-19 is ACE2 (angiotensin-converting enzyme 2), which acts as a double-edged sword, because ACE2 increases the tissue anti-inflammatory response but it is also the entry receptor for the virus. There is an important controversy on several drugs that regulate RAS activity and possibly ACE2, and are widely used, particularly by patients most vulnerable to severe COVID-19. In the lung of healthy rats, we observed that candesartan (an angiotensin type-1, AT1, receptor blocker; ARB) and captopril (an ACE inhibitor; ACEI) up-regulated expression of tissue ACE2 and RAS anti-inflammatory axis receptors (AT2 and Mas receptors). This effect was particularly pronounced in rats with metabolic syndrome (obesity, increased blood pressure and hyperglycemia) and aged rats. Treatment of cultures of human type-II pneumocytes with candesartan or captopril induced up-regulation of ACE2 expression in cells. Treatment with viral spike protein induced a decrease in full-length (i.e. transmembrane) ACE2, an increase in levels of a short intracellular ACE2 polypeptide and an increase in ADAM17 activity in cells, together with an increase in levels of soluble ACE2 and major proinflammatory cytokines in the culture medium. Spike protein-induced changes and levels of spike protein internalization in cells were inhibited by pretreatment with the above-mentioned drugs. The results suggest that these drugs increase ACE2 levels and promote the anti-inflammatory RAS axis in the lung. Furthermore, possible up-regulation of viral entry by the drug-induced increase in expression of transmembrane ACE2 is counteracted by additional mechanisms, particularly by drug-induced inhibition of ADAM17 activity.

Functional Complexes of Angiotensin-Converting Enzyme 2 and Renin-Angiotensin System Receptors: Expression in Adult but Not Fetal Lung Tissue.

Angiotensin-converting enzyme 2 (ACE2) is a membrane peptidase and a component of the renin-angiotensin system (RAS) that has been found in cells of all organs, including the lungs. While ACE2 has been identified as the receptor for severe acute respiratory syndrome (SARS) coronaviruses, the mechanism underlying cell entry remains unknown. Human immunodeficiency virus infects target cells via CXC chemokine receptor 4 (CXCR4)-mediated endocytosis. Furthermore, CXCR4 interacts with dipeptidyl peptidase-4 (CD26/DPPIV), an enzyme that cleaves CXCL12/SDF-1, which is the chemokine that activates this receptor. By analogy, we hypothesized that ACE2 might also be capable of interactions with RAS-associated G-protein coupled receptors. Using resonance energy transfer and cAMP and mitogen-activated protein kinase signaling assays, we found that human ACE2 interacts with RAS-related receptors, namely the angiotensin II type 1 receptor (AT1R), the angiotensin II type 2 receptor (AT2R), and the MAS1 oncogene receptor (MasR). Although these interactions lead to minor alterations of signal transduction, ligand binding to AT1R and AT2R, but not to MasR, resulted in the upregulation of ACE2 cell surface expression. Proximity ligation assays performed in situ revealed macromolecular complexes containing ACE2 and AT1R, AT2R or MasR in adult but not fetal mouse lung tissue. These findings highlight the relevance of RAS in SARS-CoV-2 infection and the role of ACE2-containing complexes as potential therapeutic targets.

SARS-CoV-2 as a Factor to Disbalance the Renin-Angiotensin System: A Suspect in the Case of Exacerbated IL-6 Production.

Fever in infections correlates with inflammation, macrophage infiltration into the affected organ, macrophage activation, and release of cytokines involved in immune response, hematopoiesis, and homeostatic processes. Angiotensin-converting enzyme 2 (ACE2) is the canonical cell surface receptor for SARS-CoV-2. ACE2 together with angiotensin receptor types 1 and 2 and ACE2 are components of the renin-angiotensin system (RAS). Exacerbated production of cytokines, mainly IL-6, points to macrophages as key to understand differential COVID-19 severity. SARS-CoV-2 may modulate macrophage-mediated inflammation events by altering the balance between angiotensin II, which activates angiotensin receptor types 1 and 2, and angiotensin 1-7 and alamandine, which activate MAS proto-oncogene and MAS-related D receptors, respectively. In addition to macrophages, lung cells express RAS components; also, some lung cells are able to produce IL-6. Addressing how SARS-CoV-2 unbalances RAS functionality via ACE2 will help design therapies to attenuate a COVID-19-related cytokine storm.