Clinical factors associated with augmentation treatment with second-generation antipsychotics and lithium in major depression – Results from a European multicenter study

This cross-sectional European multicenter study with retrospective assessment of treatment response sought to determine variables associated with the administration of augmentation strategies with second-generation antipsychotics (SGAs) and lithium in the pharmacotherapy of major depressive disorder (MDD). In 349 DSM-IV-TR MDD patients, differences in socio-demographic, clinical, treatment, and pharmacological features between participants receiving add-on treatment of their antidepressants with either SGAs (n = 318) or lithium (n = 31) were investigated using analyses of covariance, chi-squared tests, and binary logistic regression analyses. As only significant between-group difference, we found SGA augmentation (compared with lithium augmentation) to be associated with high depressive symptom severity expressed by a higher mean Montgomery and Åsberg Depression Rating (MADRS) total score (27.19 ± 11.35 vs 18.87 ± 12.88, F = 14.82, p = <.0001) and a higher mean 21-item Hamilton Rating Scale for Depression (HAM-D) total score (21.27 ± 9.30 vs 13.74 ± 9.11, F = 18.60, p = <.0001). No significant differences for socio-demographic features, psychotic symptoms, suicidality, psychiatric and somatic comorbidities, antidepressant pharmacotherapy, and other add-on medications could be seen. Even if there was no significant superiority of one augmentation strategy with regard to treatment response pattern, a trend whereupon adjunctive SGAs were more likely dispensed in treatment-resistant and difficult-to-treat MDD conditions could be observed. In terms of the prescription pattern, we could demonstrate that lithium is less frequently used than SGAs in the clinical routine care which may reflect the need of continuous plasma level determinations and the anticipation of adverse effects.