Medical and Psychiatric Comorbidities in Bipolar Disorder: Insights from National Inpatient Population-based Study

Objectives The objective of this study was to analyze the differences in the prevalence and association of medical and psychiatric comorbidities in bipolar disorder (BD) patients versus the general inpatient population. Methods A cross-sectional analysis was conducted using the national inpatient sample (NIS). Using the international classification of diseases, ninth revision (ICD-9) diagnostic codes, we extracted the BD inpatients and then obtained information about comorbidities. The odds ratio (OR) of comorbidities in BD inpatients were evaluated using a logistic regression model. Results Hypertension (31.1%), asthma (11.7%) and diabetes, obesity, and hypothyroidism (11% each) were the prevalent medical comorbidities found in BD inpatients. Hypothyroidism, asthma, and migraine were seen in BD inpatients (OR 1.59, OR 1.37 and OR 1.23; respectively) compared to general inpatients. Drug abuse (33.5%), anxiety disorders (31.8%), and alcohol abuse (18.3%) were the most prevalent psychiatric comorbidities in BD inpatients. They had a seven-fold higher likelihood of comorbid borderline personality disorders compared to general inpatients. Among other psychiatric comorbidities, the odds of the association were higher for drug abuse (OR 4.33), ADHD (OR 3.06), and PTSD (2.44). Conclusion A higher burden of medical and psychiatric comorbidities is seen in BD inpatients compare to the general inpatient population. A collaborative care model is required for early diagnosis and management of these comorbidities to improve the health-related quality of life.