Risk Factors and Total Sodium Dose Associated With Hyponatremia Overcorrection: A Retrospective Cohort Study

Hyponatremia overcorrection may cause serious irreversible neurologic impairment. Although studies have identified the risk factors and optimal treatment regimens for hyponatremia, findings have been inconsistent; furthermore, current treatment guidelines provide recommendations that do not consider patient-related factors.

This study aimed to identify the risk factors of hyponatremia overcorrection and assess the relationship between administered sodium dose and subsequent changes in serum sodium levels.

This retrospective cohort study included 212 patients with hyponatremia admitted to the emergency department of a tertiary medical center. The primary study outcome was hyponatremia overcorrection defined as >12 mEq/L increase in serum sodium 12 h after the baseline. The secondary study outcome was hyponatremia overcorrection defined as >8 mEq/L increase in serum sodium at 12 h after the baseline.

Overcorrection of >8 and 12 mEq/L at 12 h occurred in 39 (18.4%) and 16 (7.5%) patients, respectively. Multivariable logistic regression analysis revealed that low urine osmolality (<150 mOsm/kg) and total sodium dose of >4.6 mEq/kg over 12 h were significant risk factors of hyponatremia overcorrection. Serum sodium changes were significantly higher in the group with >4.6 mEq/kg/12 h than in the group with >3.4 mEq/kg/12 h (9.4 ± 5.3 mEq/L vs. 5.1 ± 4.0 mEq/L, p = 0.001).

Low urine osmolality and total sodium dose of >4.6 mEq/kg/12 h were significant risk factors of overcorrection in patients with hyponatremia. Calculating the total sodium dose might help prevent hyponatremia overcorrection.