NMDA antibodies increased in mania patients

By Mark Cowen

Patients with bipolar disorder show increased levels of antibodies to the NR2 subunits of the N-methyl-D-aspartate (NMDA) receptor during periods of acute mania, researchers report.

"Our findings support a role for antibodies to the NMDA receptor in the pathogenesis of acute mania," write Faith Dickerson (The Stanley Research Program at Sheppard Pratt, Baltimore, Maryland, USA) and team in Bipolar Disorders.

The NMDA receptor complex, part of the glutamatergic system, plays an important role in the regulation of neuronal communication, and previous studies have indicated that the glutamatergic system is involved in the pathophysiology of mania.

As antibodies to the NR2 subunits of the NMDA receptor have been shown to adversely affect glutamate functioning, the team investigated serum levels of these antibodies in 60 patients with bipolar disorder who were admitted to hospital with acute mania, 295 patients with other psychiatric disorders, and 170 nonpsychiatric controls.

The bipolar disorder patients were assessed for serum antibody levels at the time of hospital admission, an average 6 days after admission, and at the 6-month follow up.

The researchers note that the mean Young Mania Rating Scale score fell significantly among the bipolar disorder patients during the study period, from 18.4 at baseline to 7.3 at follow up, indicating a reduction in symptoms.

After adjustment for age, gender, ethnicity, medication use, and other factors, the researchers found that the bipolar disorder patients with mania had significantly increased levels of antibodies to NR2 compared with other psychiatric patients and controls both at the time of admission and 6 days after admission.

However, there were no significant differences among the groups regarding antibody levels to NR2 at the 6-month follow up.

There was a progressive decrease in antibody levels to NR2 over the three time points among the bipolar disorder patients, the researchers note.

Dickerson et al conclude: "The possible role of immune modulatory therapy in individuals with mania who have increased levels of antibodies to NR2 should be the subject of future clinical trials.

"The successful conclusion of such trials might lead to new modalities for the treatment of mania in some individuals."

Licensed from medwireNews with permission from Springer Healthcare Ltd. ©Springer Healthcare Ltd. All rights reserved. Neither of these parties endorse or recommend any commercial products, services, or equipment.