Prescription patterns following first-line new generation antidepressants for depression in Japan: a naturalistic cohort study based on a large claims database

Background: Several studies have described real-world prescription patterns of first-line antidepressants for depression but little is known about their fate in terms of duration, intensity and changes.

Methods: An inception cohort of new onset non-psychotic depression initiating antidepressant treatment with a new generation antidpressive agent was identified in a large health insurance claims database in Japan between 2009 and 2010. The duration and intensity of first-line antidepressants, the timing and kind of second-line antidepressants and the total duration of antidepressant treatment were examined.

Results: We identified 1592 patients. The starting dose and the maximum dose attained with the first-line agent appeared to be largely in line with the guideline recommendations although the latter tended toward the minimum of the recommended range. The continuity of the first-line antidepressant was far below the guideline recommendations, with 28% never returning after the initial prescription and 55% dropping out within 3 months. Of all the first-line antidepressants, 14% were subsequently augmented by another psychotropic agent while 17% were switched to another antidepressant after a median of 3 or 2 months, respectively. The choice of the second-line agents varied extremely widely. The total duration of antidepressant therapy was as short as a median of 4 months, with 68% stopping treatment by 6 months.

Limitations: The diagnosis of non-psychotic unipolar depression in the claims database analyses remains approximate.

Conclusions: The current guidelines are grossly out of touch with the clinical realities. On the one hand, guidelines need to reflect the real-world practices; on the other hand clinicians should limit their treatment options and allow evidence-based comparative effectiveness research among them so that patients shall no longer be given less effective and more effective treatments without being able to distinguish among them.