Sodium alterations impair the prognosis of hospitalized patients with COVID-19 pneumonia

Abstract

Objective: Dysnatremia is common in hospitalized patients, often worsening the prognosis in pneumopathies and critical illnesses. Information on COVID-19-related hyponatremia is partially conflicting, whereas data on hypernatremia in this context are scarce. We assessed, in a cohort of COVID-19 inpatients: the prevalence of sodium alterations at admission and throughout their hospitalization; their association with inflammation/organ damage indexes; their short-term prognostic impact. Study design and methods: 117 patients (81 males, 64±13 years) hospitalized for COVID-19 between 1st March and 30th April 2020 were retrospectively followed-up for their first 21 days of stay by collecting all serum sodium measurements, basal CRP and serum lactate levels, maximum IL-6 and information on care setting, required ventilation, length of hospitalization, in-hospital death. Results: At admission, 26.5% patients had hyponatremia, 6.8% had hypernatremia. During their hospitalization, 13.7% patients experienced both disorders (“mixed dysnatremia”). Lower sodium levels at admission were correlated with higher CRP (p=0.039) and serum lactate levels (p= 0.019), but not IL-6. Hypernatremia and a wider sodium variability were associated to maximum required ventilation, need of ICU assistance and duration of the hospitalization. Mean estimated time to ICU admission was 20 days shorter in patients exposed to sodium alterations at any time of their hospital course (Log-Rank test p=0.032). Conclusions: Sodium alterations frequently affect hospitalized COVID-19 patients. Hyponatremia could indicate pulmonary involvement, whereas hypernatremia is associated to prolonged hospitalization and need for intensive care/mechanical ventilation, particularly when resulting from prior hyponatremia. Optimizing in-hospital sodium balance is crucial to improve patients’ prognosis.

Laboratory parameters associated with prolonged hospital length of stay in COVID-19 patients in Johannesburg, South Africa

“…[34,41,42] On the contrary, admission hypernatraemia or the development of hypernatraemia during hospitalisation have been associated with increased mortality and death. [30,35,36,39,40] Similarly, we found a correlation between hypernatraemia and a long hospital stay. It has been reported that SARS-CoV-2 binds to the angiotensin-converting enzyme 2 receptor in kidney tubules.…”

“…Dysnatraemia in COVID-19 hospitalised patients has generally been associated with poorer outcomes. [30][31][32][33][34][35][36][37][38][39][40][41][42] Both hypernatraemia and hyponatraemia, at admission, have been associated with increased mortality, ICU admission, longer hospitalisation and mechanical ventilation. [32,37,38] Specifically, hyponatraemia was found to be relatively common in hospitalised COVID-19 patients and to be associated with severe illness and increased in-hospital mortality.…”

Hypernatremia increases mortality in patients admitted by COVID-19: A Retrospective longitudinal study with 1000 patients

“…We evaluated 1,000 patients hospitalized with COVID-19 and detected that hypernatremia was largely frequent, affecting 76.1% of individuals who died. Our results are consistent with those of other relevant investigations to date [7,[13][14][15]21].…”

“…These associations were observed in the present study, allowing a clinical characterization of COVID-19 patients in southern Brazil, reproducing the ndings of risk factors for mortality. On the other hand, hyponatremia could indicate pulmonary involvement, whereas hypernatremia is associated with prolonged LOS and the need for intensive care/mechanical ventilation, particularly when resulting from prior hyponatremia [14].…”

“…Dysnatremia (serum sodium level > 145mmol/L or < 135mmol/L) is the most common electrolyte disturbance that has been associated with a worse prognosis for hospitalized COVID-19 patients [10][11][12][13][14][15]. It was also previously demonstrated that hospitalized patients with community-acquired pneumonia (CAP) caused by other pathogenic microorganisms presenting hyponatremia and hypovolemia have a higher risk of death [13].…”