Medical comorbidity in a bipolar outpatient clinical population.

The presence of medical illnesses among inpatients with bipolar disorder is known to complicate treatment and lengthen hospital stay. However, except for a few specific diseases, little is known about prevalence of medical illnesses in bipolar outpatients and the effect it may have on treatment. The authors sought to assess the presence of medical illnesses in a large outpatient clinical sample of bipolar patients, and the effect that medical illnesses may have on the clinical assessment and treatment of the underlying bipolar disorder. Using the Duke University Medical Center clinical database, the authors categorized the medical diagnoses of 1379 patients who were treated with bipolar disorder from 2001 to 2002 through outpatient psychiatric clinics. The prevalence of medical comorbidities was examined, as well as the effect their presence had on the clinician's assessment of disease severity and time to improvement. As expected, medical comorbidities increased with age. The most common systemic illnesses in bipolar outpatients were Endocrine and Metabolic Diseases (13.6% of the sample), Diseases of the Circulatory System (13.0%), and Diseases of the Nervous System and Sense Organs (10.7%). Significant specific diseases included cardiovascular diseases/hypertension (10.7%), COPD/asthma (6.1%), diabetes (4.3%), HIV infection (2.8%), and hepatitis C infection (1.9%). Clinicians assessed greater severity of illness in patients with increasing numbers of comorbid conditions; however, the time to recovery was not significantly effected by the presence of medical comorbidity. In conclusion, comorbid medical illnesses are common in bipolar outpatients, increasing with age. HIV rates may be increased relative to population norms. Their presence compounds the severity of the illness at time of presentation.