Prevalence and association of dysnatremia with outcomes in hospitalized COVID-19 patients

ABSTRACT

Background: Studies have reported both hypo and hypernatremia in patients hospitalized with COVID-19. We sought to examine the prevalence and association of dysnatremia with clinical outcomes among hospitalized COVID-19 patients at the Mount Sinai Health System. Methods: We included 5,712 patients with COVID-19 who were ≥18 years old and hospitalized for ≥24 hours in the Mount Sinai Health System. Patients with ESKD, who received dialysis within the first 24 hours were excluded. We evaluated the association between serum sodium on admission (first level within 24 hours from admission) and the lowest serum sodium during hospitalization with AKI, IMV requirement, and in-hospital mortality using multivariable logistic regression models. Results: The median age of patients was 67 (55-78) years, 57% were male, and median serum creatinine was 1.0 (IQR, 0.7-1.4) mg/dL. On hospital admission, 6% had moderate/severe hyponatremia (<130 mEq/L), 18% had mild hyponatremia (130-134 mEq/L), and 8% had hypernatremia (>145 mEq/L). After adjustment for demographics, comorbidities, and admission lab values, the adjusted OR for moderate/ severe hyponatremia, mild hyponatremia, and hypernatremia on admission, compared to normal serum sodium, for in-hospital mortality were 1.59 (1.16-2.19), 1.42 (1.14-1.76) and 2.91 (2.16-3.93), respectively (Figure 1A). Dysnatremias during hospitalization were also associated with all three outcomes, except IMV requirement was not significantly associated with hypernatremia. (Figure 1B). Conclusions: Both hypo-and hypernatremia on hospital admission and during hospitalization for COVID-19 were independently associated with AKI, IMV requirement, and in-hospital mortality. It is highly likely that dysnatremias are a marker for severity of illness and not causal for the adverse outcomes in COVID-19.