Associação entre o Antagonismo do Sistema Renina-Angiotensina-Aldosterona e a Mortalidade Relacionada à COVID-19 em Pacientes com Hipertensão Relacionada ao Sobrepeso/Obesidade: um Estudo Retrospectivo de Coorte / Association between RAAS Antagonism and COVID-19-related Mortality in Patients with Overweight/Obesity-related Hypertension: A Retrospective Cohort Study

Resumo Fundamento Os bloqueadores dos receptores da angiotensina (BRA) e os inibidores da enzima conversora da angiotensina (IECA) aumentam a expressão de ACE2, que é um receptor para entrada de SARS-CoV-2 nas células. Embora as evidências sugiram que os IECA/BRA são seguros entre a população geral com COVID-19, sua segurança em pacientes com hipertensão relacionada ao sobrepeso/obesidade merece uma avaliação mais aprofundada. Objetivo Avaliamos a associação entre o uso de IECA/BRA e a gravidade da COVID-19 em pacientes com hipertensão relacionada ao sobrepeso/obesidade. Métodos O presente estudo incluiu 439 pacientes adultos com sobrepeso/obesidade (índice de massa corporal ≥ 25 kg/m2) e hipertensão, diagnosticados com COVID-19 e internados no University of Iowa Hospitals and Clinic entre 1º de março e 7 de dezembro de 2020. Foram avaliadas a mortalidade e a gravidade da COVID-19 com base no tempo de internação hospitalar, internação em unidade de terapia intensiva, uso de oxigênio suplementar, ventilação mecânica e uso de vasopressores. A regressão logística multivariável foi usada para examinar as associações do uso de IECA/BRA com a mortalidade e outros marcadores de gravidade de COVID-19, com um alfa bilateral definido em 0,05. Resultados A exposição aos BRA (n = 91) e IECA (n = 149) antes da hospitalização foi significativamente associada a menor mortalidade ( odds ratio [OR] = 0,362, intervalo de confiança [IC] de 95% 0,149 a 0,880, p = 0,025) e menor tempo de internação hospitalar (IC 95% −0,217 a −0,025, p = 0,015). Adicionalmente, os pacientes em uso de IECA/BRA apresentaram uma tendência não significativa de menor internação em unidade de terapia intensiva (OR = 0,727, IC 95% 0,485 a 1,090, p = 0,123), uso de oxigênio suplementar (OR = 0,929, IC 95% 0,608 a 1,421,p = 0,734), ventilação mecânica (OR = 0,728, IC 95% 0,457 a 1,161, p = 0,182) e vasopressores (OR = 0,677, IC 95% 0,430 a 1,067, p = 0,093). Conclusão Os resultados sugerem que pacientes internados com COVID-19 e hipertensão relacionada ao sobrepeso/obesidade que receberam IECA/BRA antes da internação apresentam menor mortalidade e COVID-19 menos grave do que aqueles que não estavam tomando IECA/BRA. Os resultados também sugerem que a exposição aos IECA/BRA pode proteger pacientes com hipertensão relacionada ao sobrepeso/obesidade de COVID-19 grave e morte.

Abstract Background Angiotensin receptor blockers (ARB) and angiotensin-converting enzyme inhibitors (ACEI) increase the expression of ACE2, which is a receptor for entry of SARS-CoV-2 into cells. Though evidence suggests that ARB/ACEI are safe among the general population with COVID-19, their safety in patients with overweight/obesity-related hypertension deserves further evaluation. Objective We assessed the association between ARB/ACEI use and COVID-19 severity in patients with overweight/obesity-related hypertension. Methods This study included 439 adult patients with overweight/obesity (body mass index ≥ 25 kg/m2) and hypertension, diagnosed with COVID-19 and admitted to University of Iowa Hospitals and Clinic from March 1 to December 7, 2020. Mortality and severity of COVID-19 were evaluated based on length of stay in hospital, intensive care unit admission, use of supplemental oxygen, mechanical ventilation, and vasopressors. Multivariable logistic regression was used to examine the associations of ARB/ACEI use with mortality and other markers of COVID-19 severity, with a two-sided alpha set at 0.05. Results Exposure to ARB (n = 91) and ACEI (n = 149) before hospitalization was significantly associated with lower mortality (odds ratio [OR] = 0.362, 95% confidence interval [CI] 0.149 to 0.880, p = 0.025) and a shorter length of stay (95% CI −0.217 to −0.025, p = 0.015). Additionally, patients using ARB/ACEI showed a non-significant trend toward lower intensive care unit admission (OR = 0.727, 95% CI 0.485 to 1.090, p = 0.123), use of supplemental oxygen (OR = 0.929, 95% CI 0.608 to 1.421, p = 0.734), mechanical ventilation (OR = 0.728, 95% CI 0.457 to 1.161, p = 0.182), and vasopressors (OR = 0.677, 95% CI 0.430 to 1.067, p = 0.093). Conclusion Results suggest that hospitalized patients with COVID-19 and overweight/obesity-related hypertension who were prescribed ARB/ACEI before admission to the hospital exhibit lower mortality and less severe COVID-19 than those who were not taking ARB/ACEI. The results also suggest that exposure to ARB/ACEI may protect patients with overweight/obesity-related hypertension from severe COVID-19 and death.

Role of leptin and obesity-related leptin resistance in the pathophysiology of metabolic syndrome

The prevalence of metabolic syndrome is high and will likely increase further as the obesity epidemic accelerates. Leptin is a peptide hormone mostly derived from adipose tissue that promotes negative energy balance. Hyperleptinemia is common in obesity and reflects increased fat mass and leptin resistance. Nevertheless, leptin resistance might not be complete as several actions of leptin, like cardiovascular sympathetic activation, might be preserved in obese subjects that are resistant to the metabolic actions of leptin (i.e. selective leptin resistance). Leptin may contribute to elevated blood pressure, hyperglycemia, dyslipidemia, pro-thrombotic and proinflammatory states found in metabolic syndrome. Notably, the renal and sympathetic actions of leptin appear to play a major role in the pathogenesis of hypertension related to obesity and the metabolic syndrome. Furthermore, the lipotoxic effect of leptin resistance is thought to be a major determinant of insulin resistance and may increase the risk of type 2 diabetes

Mechanisms of obesity-related hypertension: from insulin to leptin

Hyperinsulinemia has been classically associated with obesity-related hypertension. However, this concept has been challenged given that acute hyperinsulinemia has repeatedly failed to increase arterial pressure in humans. Most recently, leptin-dependent mechanisms have raised great interest as potential explanations for obesity-related hypertension. Despite potential depressor effects of leptin, most reports have shown that leptin increases arterial pressure probably due to sympathetic activation. Human obesity hypertension is associated with increased sympathetic activity. Thus, it is possible that hyperleptinemia in human obesity could contribute to obesity-related sympathetic activation. However, human obesity is a partial leptin resistant condition. The novel concept of selective leptin resistance may help explain leptin-induced sympathoactivation in obese subjects resistant to the metabolic effects of leptin. In this review article, we revisit insulin-dependent mechanisms reportedly associated with obesity hypertension. We also discuss leptin actions on the cardiovascular system and show experimental results that support the concept of selective leptin resistance.