International prescribing patterns for mood illness: the International Mood Network (IMN)

To show the feasibility of creating an international network that will build a common database for mood disorders research, and to present initial data on prescribing patterns worldwide.

An international research database was organized with clinicians and researchers actively treating mood disorders. Participating sites were asked to provide data on 10-50 subjects initially. This work was conducted under the auspices of a committee with representatives from North and South America, Europe, and Asia. Data was pooled from multiple sites using a centralized online system and then analyzed. Each site received IRB approval for its participation in the IMN and the Tufts Medical Center IRB provided approval for the entire project.

More than half of the population came from one country (United States) and there is the possibility of cultural bias.

Among the 186 subjects enrolled in the IMN, a majority of subjects were prescribed mood stabilizers including lithium (64%), lamotrigine (37%), valproate (31%), and carbamazepine (3%). 79% had a diagnosis of bipolar disorder type I, II or NOS and 21% had a diagnosis of MDD. 81% of subjects used antidepressants at some point. 25% experienced antidepressant-induced mania and 26% had antidepressant-related rapid cycling. Mood stabilizers were prescribed more in Europe (86%), neuroleptics in South America (70%), and antidepressants in Asia (58%).

The results confirm the diversity and feasibility of an international mood disorders database. Important regional differences in psychotropic drug treatment of mood illnesses were observed, with more mood stabilizer use in Europe and South America, and more antidepressant use in non-European populations.