A clinical trial led by University of Cincinnati researchers at the Lindner Center of HOPE found a drug was safe and effective for weight loss for patients with stable bipolar disorder.
The trial results were published in the Journal of Clinical Psychopharmacology.
Susan McElroy, MD, study primary investigator, said many effective bipolar medications have a side effect of weight gain and obesity, and abnormal eating behavior like binge eating is also common in these patients. At the same time, many weight loss drugs have a side effect of destabilizing mental illness, particularly in patients with bipolar disorder.
The trial tested a drug called liraglutide, part of a class of antidiabetic drugs called GLP-1 agonists that include the brand names Ozempic and Wegovy that also are used for weight loss.
"These drugs have some side effects, but their neuropsychiatric profile is benign," said McElroy, the Linda and Harry Fath endowed professor in the Department of Psychiatry & Behavioral Neuroscience in UC's College of Medicine and chief research officer at the Lindner Center of HOPE.
Over 40 weeks, a total of 60 patients with stable bipolar disorder who were obese or overweight were randomized to either receive liraglutide injections or a placebo. Every patient additionally received dietary counseling including recommendations about diet and exercise.
"The most important result was that the drug was efficacious for weight loss in individuals with stable bipolar disorder, and it was safe," McElroy said. "It did not destabilize the illness in any way, and we had no severe medical adverse effects either."
The researchers additionally found that liraglutide statistically reduced binge eating behavior based on self-reported data and significantly reduced patients' hemoglobin A1C, a measure of average blood sugar levels used to diagnose and manage prediabetes and diabetes.
McElroy said limitations of the study include its small sample size and a high dropout rate, although more patients on placebo dropped out compared to those taking liraglutide.
"A 40-week study for people with bipolar disorder is a long time, and if there was any sign of their illness destabilizing, we would terminate the study for safety reasons," she said. "More terminations for mood instability on placebo again indicates that we think at least in this population that the drug appeared safe for weight loss."
Other studies have found similar results of safe weight loss with no negative impacts on mental health in patients with schizophrenia. McElroy said she hopes to see more research into this class of drugs for people with mental disorders with or without obesity, in addition to more research in general at the intersection of mental illness and obesity.
"There are many, many studies on obesity with diabetes, obesity with heart disease, but there's very few studies on obesity with mental illness," she said. "It's just an area that is a wide open frontier."
