Canada: A new study published in NEJM: Evidence has found that rapid correction of serum sodium is a common occurrence in patients with hyponatremia, but osmotic demyelination syndrome (ODS) is rare.
Hyponatremia is a condition in which there is a low level of sodium in the blood. Osmotic demyelination syndrome (ODS) is a rare but potentially devastating neurologic complication of hyponatremia that can lead to severe disability or death. The objective of this study was to determine the percentage of patients who developed ODS after being brought to the hospital with hyponatremia.

The study included 22,858 participants and was conducted by researchers at five academic hospitals in Toronto, Canada, and included a large, contemporary, multicenter cohort of patients admitted to the hospital with hyponatremia. The participants included in the study were adults with serum sodium levels less than 130mmol/L.
The following key takeaways were revealed by the study:
1. The mean initial serum sodium was 125 mmol/l, 11.9% of patients had serum sodium from 110 to 119 mmol/l and 1.2% had serum sodium less than 110 mmol/l.
2. Rapid correction of serum sodium occurred in 3632 (17.7%) admissions.
3. Twelve patients developed ODS (0.05%)
4. Seven (58%) patients who developed ODS did not have rapid correction of serum sodium.
The study concludes that although rapid correction of serum sodium is common in patients with hyponatremia, Osmotic demyelination syndrome (ODS) is a rare complication.
“However, more studies with a higher number of patients with ODS are needed to better understand potential causal factors for ODS. This study is a valuable contribution to the understanding of hyponatremia and its potential complications.” added the researchers of the study.
Reference:
MacMillan T., Shin S., Topf J., Kwan J., Weinerman A., et al.; Osmotic Demyelination Syndrome in Patients Hospitalized with Hyponatremia; NEJM Evid 2023;2(4) VOL. 2 NO. 4; doi: 10.1056/EVIDoa2200215