People with an eating disorder, electrolyte abnormality faced increased risk for death

Key takeaways:

• Electrolyte abnormalities in individuals with newly diagnosed eating disorders tied to increased risk for mortality, acute kidney injury and bone fracture.
• The results underline the importance of screening for electrolyte levels.

Individuals with eating disorders and abnormal electrolyte levels faced an increased risk for several adverse health outcomes, including death and hospitalization, a retrospective cohort study showed.

The results, published in Lancet Psychiatry, suggest that monitoring for and correcting electrolyte disturbances among those with a newly diagnosed eating disorder may help reduce excess mortality risk, according to researchers.

“These findings might inform explicit mention of electrolyte abnormalities in the criteria we use to assess the severity of eating disorders,” Marco Solmi, MD, medical director of the Regional Eating Disorder Program at The Ottawa Hospital in Canada and lead study author, said in a press release.

Although electrolyte abnormalities are common in people with eating disorders, “to our knowledge, no study has investigated if electrolyte abnormalities in people with eating disorder are associated with mortality,” Solmi and colleagues wrote.

The researchers conducted a retrospective population-level cohort study that examined over 10 years’ worth of health records belonging to 6,163 patients aged 13 years or older who were diagnosed with an eating disorder and had an electrolyte level test within 1 year of their diagnosis.

Most individuals received a diagnosis of an eating disorder not otherwise specified (59.3%). The most common disorders included anorexia nervosa (22.1%) and bulimia nervosa (15.2%).

Overall, 32% of the cohort had electrolyte abnormalities, while the most common electrolyte abnormalities reported included hypokalaemia (50%), hyponatraemia (37.8%) and hypernatraemia (21.1%).

Between 2008 to 2019, researchers reported a mortality rate of 15.7% among those with abnormal electrolyte levels compared with 5.6% in those without (adjusted HR = 1.23; 95% CI, 1.03-1.48).

They also observed links between several other outcomes and electrolyte abnormality, including:

• hospitalization (aHR = 1.35; 95% CI, 1.25-1.46);
• acute kidney injury (aHR = 1.91; 95% CI, 1.5-2.43);
• bowel obstruction (aHR = 1.62; 95% CI, 1.12-2.35);
• bone fracture (aHR = 1.4; 95% CI, 1.1-1.78); and
• chronic kidney disease (aHR = 1.44; 1.17-1.77).

The results did not show any ties between abnormal electrolyte levels or increased risk for infection or a heart disease event.

Solmi and colleagues explained there are several potential mechanisms behind the associations observed.

For example, “potassium and magnesium abnormalities predispose patients to cardiac arrhythmias,” they wrote.

They added that recurrent binging, purging and restricting behaviors “might result in dehydration and subsequent electrolyte abnormalities that can lead to recurrent acute kidney injury, which is associated with progressive chronic kidney disease over time.”

There were some study limitations identified by the researchers. Due to the analysis’ observational design, the researchers could not confirm a causal relationship between electrolyte abnormality and death or other negative outcomes.

Additionally, the data did not allow Solmi and colleagues to account for treatment refusal, “which might shape outcomes.”

Ultimately, “these findings underscore the importance of testing for electrolyte levels in people suffering from eating disorders, and then acting on those results to potentially reduce the risk of death or other severe outcomes,” Nicholas Fabiano, a psychiatry resident at The Ottawa Hospital and study co-author, said in the release.

References:

• Abnormal electrolyte levels in people with eating disorders may increase risk of death, poor health outcomes. Available at:https://www.ices.on.ca/news-releases/abnormal-electrolyte-levels-in-people-with-eating-disorders-may-increase-risk-of-death-poor-health-outcomes/. Published Sept. 17, 2024. Accessed Sept. 30, 2024.
• Solmi M, et al. Lancet Psychiatry. 2024;doi: 10.1016/S2215-0366(24)00244-X.