CF Liu, HSR&D, VA Puget Sound Health Care Center; EF Chaney, HSR&D, VA Puget Sound Health Care Center; S Hedrick, HSR&D, VA Puget Sound Health Care Center

Objectives: The Health Plan Employer Data and Information Set (HEDIS), a set of standardized performance measures used by more than 90% of nation's managed care organizations, has included three new measures for antidepressant medication management for new depression episodes in the year 2000 – optimal practitioner contacts for medication management, effective acute phase treatment, and effective continuation phase treatment. This study examines the feasibility of applying the latter two measures in a VA Primary Care population using administrative databases. The effective acute phase treatment measure assesses the percentage of the eligible population who initiated and remained on an antidepressant medication for at least 84 days. The effective continuation phase treatment is the percentage of the eligible population who remained on antidepressant medication for at least 180 days.

Methods: We constructed the two HEDIS measures using patients seen in the Seattle VA Primary Care Clinic during 1999. Outpatient pharmacy information, ICD-9-CM codes, and utilization data were obtained from the VISN 20 data warehouse. We applied the HEDIS specification to identify the eligible population - the denominator of the two rates. Patients with major depression are defined as individuals with one principal diagnosis in any outpatient or inpatient setting, or with one secondary diagnosis in any inpatient discharge, or two secondary diagnoses on two different dates in any outpatient setting. To qualify as a new episode, two criteria must be met (1) a 120 day negative diagnosis history (without a depression diagnosis) prior to the date of the earliest depression encounter in 1999, and (2) a 90 day negative medication history (without any antidepressant medication) prior to the prescription filled for the earliest depression encounter. Finally, we identified the numbers of patients who remained on an antidepressant medication at least 84 days (acute phase) and at least 180 days (continuation phase).

Results: In 1999, there were 28,466 unique GIMC patients and 1,492 had a diagnosis of major depression.. In several steps, we excluded 681 patients with positive depression diagnosis history, 295 patients not receiving antidepressant medication treatment, 246 patients with positive medication history, and 5 patients with an acute mental health or substance abuse inpatient hospitalization during the treatment period. Thus two-hundred sixty-five patients out of 1,492 were identified with new episodes of depression Among this eligible population, 161 patients had an 84-day treatment of antidepressant medication and 135 patients had a180 day treatment of antidepressant medication. In other words, 61% of the eligible population had effective treatment in the active phase, and 51% had effective treatment in the continuation phase.

Conclusions: This study found that the HEDIS antidepressant medication management has only marginal utility in a VA Primary Care population. The study shows that only 18% (265 out of 1,492) of depression patients were classified to have a new episode of depression. The vast majority of depression patients in the VA have chronic depression and receive care that cannot be assessed using the HEDIS measures. For treatment of new depression episodes, the VA primary care is very comparable to the average managed care organizations (58.8% for the acute phase and 42.2% for the continuation phase).

Impact: Depression is the second most prevalent medical condition in the VA. The HEDIS antidepressant medication management measures may not be suitable in the VA because only a small subset of depression patients have a new episode. However, for new depression episode, the VA primary care is very comparable to other managed care organization in antidepressant management.