Abnormal electrolyte levels in people with eating disorders may increase risk of death and health problems

A study published in The Lancet Psychiatry The study authors found that 32% of people with an eating disorder had abnormal electrolyte levels, which were associated with a higher risk of death from all causes. The article is titled “Adverse outcomes and mortality in people with eating disorder-related electrolyte abnormalities: a population-based cohort study in Ontario, Canada.”

The study, led by researchers at ICES and The Ottawa Hospital, found that electrolyte abnormalities were also linked to the development of other serious health problems, including chronic kidney disease, bone fracture, intestinal obstruction and acute kidney injury.

This is one of the first large studies to identify a significant risk factor for mortality and poor health outcomes in people with eating disorders. Electrolytes, such as potassium and sodium, can affect how the body functions. It is common for people with eating disorders to have electrolyte abnormalities due to symptoms such as purging, laxative use, and dehydration.

“These findings may inform the explicit inclusion of electrolyte abnormalities in the criteria we use to assess the severity of eating disorders,” says lead author Dr. Marco Solmi, medical director of the Regional Eating Disorders Program at The Ottawa Hospital and director of research in the Department of Psychiatry at the University of Ottawa.

The researchers included more than 6,000 people aged 13 and older who were diagnosed with an eating disorder and had an electrolyte level test within one year of their diagnosis, as recorded in a hospital or emergency department record in the province of Ontario, Canada.

Health outcomes and mortality

Analyzing medical records between 2008 and 2019, the researchers found that:

• Most people included in the study were diagnosed with an eating disorder not otherwise specified – an eating disorder that does not meet the criteria for anorexia, bulimia and binge eating disorder (59%) – followed by anorexia nervosa (22%) and bulimia nervosa (15%).

• The average age was 27 years and 89% were women.

• 1,987 people (32%) had an electrolyte abnormality and several had comorbid health problems.

• Among those with an electrolyte disorder, 16% died, compared with 6% of those without an electrolyte abnormality.

• Electrolyte abnormalities were also associated with a higher risk of hospitalization and other serious health problems, but not with a risk of infection or heart disease.

“These findings highlight the importance of testing electrolyte levels in people with eating disorders and then acting on those results to potentially reduce the risk of death or other serious outcomes,” said Dr. Nicholas Fabiano, co-senior author of the study and a psychiatry resident at The Ottawa Hospital and the University of Ottawa.

Patient education and awareness also have a role to play.

“Eating disorders are illnesses that patients often deny or do not appreciate the impact on their health. This study now shows that eating disorders severe enough to cause electrolyte disturbances have major impacts on patients’ long-term health,” said lead author Dr. Gregory Hundemer, ICES Associate Scientist, nephrologist and Lorna Jocelyn Wood Chair in Kidney Research at The Ottawa Hospital, and assistant professor at the University of Ottawa.

Finally, the researchers suggest that the findings may help redefine how clinicians assess the severity of eating disorders, which is currently based on the patient’s body mass index and the frequency of behaviors such as binge eating episodes.

Electrolyte abnormalities may be observed in patients who do not fit the most typical presentations of eating disorders and could ultimately help improve the care of these patients and reduce their risk of death or other negative outcomes.