The Changing Face of Osmotic Demyelination Syndrome

Objective To describe the long-term outcomes of osmotic demyelination syndrome (ODS) in an updated cohort.

Methods We performed a retrospective medical records review of cases of ODS at the Massachusetts General and Brigham and Women's Hospitals using International Classification of Diseases–9th edition codes and a text-based search for central pontine myelinolysis, extrapontine myelinolysis, and osmotic demyelination syndrome (1999–2018). Cases were individually selected based on patients having neuroimaging and symptoms consistent with ODS and no other potentially explanatory etiology. Modified Rankin scale (mRS) scores were extracted at prehospitalization, hospital discharge, 6 months post discharge, and the most recently available clinical visit.

Results We identified 45 cases of ODS (mean age 48.4 years, range 0.07–75 years; 58% female patients). Common comorbidities included liver disease (27%, n = 12), alcoholism (44%, n = 20), and kidney failure (20%, n = 9). Twenty-nine percent of patients had a rapid correction of hyponatremia. Twenty-nine percent had other electrolyte abnormalities. Only 59% (24/41) of patients with complete electrolyte data had abnormalities that could explain their ODS. At the 6-month follow-up, 16% of the patients were dead and 60% of patients had minimal-to-no disability (mRS 0–2).

Conclusions ODS has a diverse range of clinical presentations. Not all patients have electrolyte abnormalities. The prognosis is generally favorable, although 1 in 6 patients had died at 6 months, likely because of underlying disease states.