Changes in the pattern of antidepressant use upon the introduction of the new antidepressants: A prescription database study

Objective: To study whether the newer antidepressants have changed the patterns of antidepressant use, and whether the claimed better adverse effect profile of the newer antidepressants is reflected in their use as monitored by a prescription database. Method: By means of a prescription database (OPED), the use of antidepressants from 1991 to 1993 in Odense, Denmark, was analysed. Results: The 1-year prevalence of antidepressant use increased significantly from 1.60% to 2.00%, which still is below the claimed 1-year prevalence of depression of at least 5%. The increase was mainly due to a rapidly increasing use of the newer antidepressants, accompa nied by a moderate decline in the use of older antidepressants (mainly tricyclic antidepressants). The patterns of antidepressant use were very polymorphic, with about 5% being on continuous use for all 3 years and groups of each 20-30% being treated with: (I) several series or (2) one series or (3) only by one prescription. The share of patients presenting only one prescription (20%) was the same for older and newer antidepressants. Likewise, the rate of shifts from older to newer antidepressants or Vice versa was the same (7% vs 6%). The duration of treatment did not differ much between older and newer antidepressants. Relative to the defined daily dose (DDD), the older antidepressants were given in much lower doses (median 0.63 DDD) than the newer antidepressants (median 1.05 DDD). Conclusion: It is concluded that many depressed patients are still not receiving antidepressant treatment and that the claimed better adverse effect profile of the newer antidepressants was not clearly reflected in their use.