In response to a high salt intake, salt-sensitive hypertensive individuals retain more sodium and manifest a rise in blood pressure greater than that in salt-resistant individuals. In this study, we tested whether salt sensitivity might be related at least in part to reduced secretion of atrial natriuretic peptide (ANP) or to abnormal nitric oxide production. We measured plasma ANP and NO2+NO3 in 7 normotensive individuals and 13 salt-sensitive and 14 salt-resistant blacks with essential hypertension under conditions of low (10 mEq/d) and high (250 mEq/d) salt intake. To evaluate possible racial differences in ANP secretion, we also measured plasma ANP in 6 salt-sensitive and 8 salt-resistant hypertensive whites during low and high salt intakes. Under low salt conditions, plasma ANP levels were not different in normotensive control subjects and salt-sensitive and salt-resistant hypertensive blacks. During high salt intake, plasma ANP levels did not change in control subjects and salt-resistant patients but decreased in salt-sensitive patients. ANP levels after high salt diet were lower (P < .01) in salt-sensitive than salt-resistant blacks. In hypertensive whites, high salt intake caused no significant change in plasma ANP. Under low salt conditions, plasma NO2+NO3 levels were higher (P < .05) in salt-sensitive (189 +/- 7.9 mumol/L) and salt-resistant (195 +/- 13.5 mumol/L) black patients than in control subjects (108 +/- 9.7 mumol/L). During high salt intake, plasma NO2+NO3 decreased significantly (P < .01) in both salt-sensitive (150 +/- 7.0 mumol/L) and salt-resistant (142 +/- 9.0 mumol/L) patients. These studies show that under conditions of high salt intake, salt-sensitive hypertensive blacks manifest a paradoxical decrease in ANP secretion. This abnormality may play a role in the reduced ability of these individuals to excrete a sodium load and in the sodium-induced rise in blood pressure. This study does not support the hypothesis that salt sensitivity depends on a deficit of nitric oxide production, but it suggests that high salt intake may alter the endothelium-dependent adaptation of peripheral resistance vessels.

Background Research surrounding COVID-19 (coronavirus disease 2019) is rapidly increasing, including the study of biomarkers for predicting outcomes. There is little data examining the correlation between serum albumin levels and COVID-19 disease severity. The purpose of this study is to evaluate whether admission albumin levels reliably predict outcomes in COVID-19 patients. Methods We retrospectively reviewed 181 patients from two hospitals who had COVID-19 pneumonia confirmed by polymerase chain reaction (PCR) testing and radiologic imaging, who were hospitalized between March and July 2020. We recorded demographics, COVID-19 testing techniques, and day of admission labs. The outcomes recorded included the following: venous thromboembolism (VTE), acute respiratory distress syndrome (ARDS), intensive care unit (ICU) admission, discharge with new or higher home oxygen supplementation, readmission within 90 days, in-hospital mortality, and total adverse events. A multivariate modified Poisson regression analysis was then performed to determine significant predictors for increased adverse events in patients with COVID-19 pneumonia. Results A total of 109 patients (60.2%) had hypoalbuminemia (albumin level < 3.3 g/dL). Patients with higher albumin levels on admission had a 72% decreased risk of developing venous thromboembolism (adjusted relative risk [RR]:0.28, 95% confidence interval [CI]:0.14–0.53, p<0.001) for every 1 g/dL increase of albumin. Moreover, higher albumin levels on admission were associated with a lower risk of developing ARDS (adjusted RR:0.73, 95% CI:0.55–0.98, p = 0.033), admission to the ICU (adjusted RR:0.64, 95% CI:0.45–0.93, p = 0.019), and were less likely to be readmitted within 90 days (adjusted RR:0.37, 95% CI:0.17–0.81, p = 0.012). Furthermore, higher albumin levels were associated with fewer total adverse events (adjusted RR:0.65, 95% CI:0.52–0.80, p<0.001). Conclusions Admission serum albumin levels appear to be a predictive biomarker for outcomes in COVID-19 patients. We found that higher albumin levels on admission were associated with significantly fewer adverse outcomes, including less VTE events, ARDS development, ICU admissions, and readmissions within 90 days. Screening patients may lead to early identification of patients at risk for developing in-hospital complications and improve optimization and preventative efforts in this cohort.

In young smokers and those with higher fasting insulin, glucose or triglyceride concentrations (factors associated with endothelial dysfunction), n-3 fatty acid levels were positively associated with flow-mediated dilatation. This raises the possibility that physiological levels of circulating n-3 fatty acids may protect the endothelium from early adulthood.