The Impact of Obesity on Brain and Behavior
In an abstract presented at the 5th Biennial Conference of the International Society for Bipolar Disorders, K. Sim and colleagues discussed the impact of increased body mass index on the integrity of white matter in the brain during a first episode of mania. The researchers found significant abnormalities in white matter integrity in the temporal pole and occipital brain regions in overweight and obese patients compared to patients of normal weight. These data highlight the need to clarify the neural mechanisms that link obesity and poorer functional outcomes in bipolar disorder.
Other investigators have reported that bipolar patients with obesity have a less robust response to naturalistic treatment compared to those of normal weight. At least one study suggested that patients with overweight and obesity experience more cognitive difficulties.
Editor’s Note: The pathophysiological mechanisms involved in the relationship between weight and brain function are not yet clear, although one possibility is that in obese patients, some fat cells in the abdominal area become too big to survive and are scavenged by other cytokine-producing cells. These inflammatory cytokines are then able to cross the blood-brain barrier, enter the brain, and affect neuronal functioning. Whether a mechanism like this is at play in relation to these particular findings remains for further investigation.
Nonetheless, these data suggest the importance of good diet, exercise, and other means of maintaining a good body weight in order to attempt to avoid some of the adverse associations of obesity with deficits in cognition, white matter integrity, and treatment outcome.
