The burden of obesity among adults with bipolar disorder in the United States

Objectives: Previous studies of clinical samples of adults with bipolar disorder (BD) suggest that there is increased prevalence of obesity and that obesity is associated with greater BD severity. We therefore examined this topic in a representative epidemiologic sample. Methods: The 2001-2002 National Epidemiologic Survey on Alcohol and Related Conditions was used to determine whether the prevalence of obesity is elevated among subjects with lifetime BD, and whether obesity is associated with greater severity of BD. Results: The age-, race-, and sex-adjusted prevalence of obesity was significantly greater among subjects with BD versus controls [ odds ratio (OR) = 1.65, 95% confidence interval (CI): 1.45-1.89, p < 0.001]. Obesity among subjects with BD was significantly positively associated with greater age, female sex, comorbid anxiety and medical conditions, and depression-related treatment utilization, and significantly negatively associated with past-year substance use disorder (SUD). In multivariable analyses, obesity among adults with BD was positively associated with age, comorbid anxiety disorders, duration of depressive episodes, and history of hospitalization for depression, and negatively associated with past-year SUD. Conclusions: The increased prevalence of obesity in BD and its association with illness severity, particularly in relation to depression, cannot be attributed to biases inherent in treatment-seeking samples. Future studies are needed to examine the direction of the observed associations and to develop preventive and treatment strategies seeking to mitigate the burden of obesity in BD.