Medical resource use among patients treated for bipolar disorder: A retrospective, cross-sectional, descriptive analysis

Background: Detailed assessments of the direct costs related to bipolar disorder and of the burden it places on the health care system are limited. Objective: In this retrospective, cross-sectional, descriptive analysis, we assessed prescription medication and other medical resource use in bipolar disorder in an insured population in the northeastern United States. Methods: Number and types of prescription drugs, medical encounters, and respective costs were derived from a New England insurer database for 1996. This analysis was purely descriptive in nature and no statistical comparisons were made. Results: Patients with bipolar disorder (N = 3120) were compared with a randomly selected age- and sex-matched nonbipolar population (N = 3120). A subgroup of patients with bipolar I disorder (n = 336), defined as having at least 1 hospital admission for mania, also were examined. A total of $2,803,673 was spent on all drugs for patients with bipolar disorder, who received a mean of 15 central nervous system (CNS) drug prescriptions per person, at an average cost of $582. This compares with $461,354 spent on drugs for nonbipolar patients, who received a mean of I CNS drug prescription per person, at an average cost of $33. Medical encounters for bipolar patients cost more than for nonbipolar patients ($16,230,840 vs $4,074,797). In patients with bipolar disorder, medical encounters for mental disorders accounted for 45.8% of costs. In nonbipolar patients, medical encounters for mental disorders accounted for 4.2% of costs. The inpatient cost for mental disorders in the bipolar patients was $4,846,311, with most of this cost (69.3%) attributed to patients with bipolar I disorder ($3,357,036). Conclusions: The number and cost of both prescriptions and health care encounters suggest that bipolar disorder, especially bipolar I, is both difficult and costly to manage.