Serum Sodium, Patient Symptoms, and Clinical Outcomes in Hospitalized Patients with COVID-19.

INTRODUCTION

Disorders of serum sodium (SNa) are common in hospitalized patients with COVID-19 and may reflect underlying disease severity. However, the association of SNa with patient-reported outcomes is not clear.

METHODS

The Brigham and Women's Hospital COVID-19 Registry is a prospective cohort study of consecutively admitted adult patients with confirmed SARS-CoV-2 infection (n = 809). We examined the associations of SNa (continuous and tertiles) on admission with: (1) patient symptoms obtained from detailed chart review; and (2) in-hospital mortality, length of stay, and intensive care unit (ICU) admission using unadjusted and adjusted logistic regression models. Covariates included demographic data and comorbidities.

RESULTS

Mean age was 60 years, 48% were male, and 35% had diabetes. The most frequent symptoms were cough (64%), fever (60%), and shortness of breath (56%). In adjusted models, higher SNa (per mmol/L) was associated with lower odds of GI symptoms (OR 0.96; 95% CI 0.92-0.99), higher odds of confusion (OR 1.08; 95% CI 1.04-1.13), in-hospital mortality (OR 1.06; 95% CI 1.02-1.11), and ICU admission (OR 1.09; 95% CI 1.05-1.13). The highest sodium tertile (compared with the middle tertile) showed similar associations, in addition to lower odds of either anosmia or ageusia (OR 0.30; 95% CI 0.12-0.74).

CONCLUSION

In this prospective cohort study of hospitalized patients with COVID-19, hypernatremia was associated with higher odds of confusion and in-hospital mortality. These findings may aid providers in identifying high-risk patients who warrant closer attention, thereby furthering patient-centered approaches to care.