Risk Factors for Overly Rapid Correction in Patients with Profound Hyponatremia: A Retrospective Cohort Study

Objective Overly rapid correction of profound hyponatremia can lead to osmotic demyelination syndrome; however, the incidence of and risk factors for overly rapid correction in patients with profound hyponatremia have not been thoroughly examined. Therefore, this study examined the incidence of and risk factors for overly rapid correction in patients with profound hyponatremia. Methods This single-center, retrospective cohort study conducted at an 865-bed teaching hospital analyzed data from 144 new inpatients with profound hyponatremia [initial serum sodium (Na⁺) level of <125 mEq/L] treated in our department between January 2014 and December 2022. Overly rapid correction was defined as serum Na⁺ correction of >10 mEq/L at 24 h. We examined the incidence of and risk factors for overly rapid correction. Results Thirty (20.8%) patients met the overly rapid correction criteria; however, none developed osmotic demyelination syndrome. A low initial serum Na⁺ level, female sex, primary polydipsia, and low frequency of follow-up in 24 h were significant independent risk factors for overly rapid correction in the multivariable analysis (p=0.020, p=0.011, p=0.014, and p=0.025, respectively). Conclusion Our study shows that a low initial serum Na⁺ level, female sex, primary polydipsia, and low frequency of follow-up within 24 h are associated with an increased risk for overly rapid correction of profound hyponatremia. Therefore, we suggest that physicians perform careful management when managing patients with profound hyponatremia with the risk factors for overly rapid correction identified in this study.