Pregabalin augmentation of antidepressants in major depression - results from a European multicenter study

Background: We aimed to investigate the prescription pattern of pregabalin augmentation of antidepressants in major depressive disorder (MDD) and to explore variables associated with add-on pregabalin treatment. Methods: 1410 MDD patients participated in this naturalistic European multicenter study with retrospective assessment of treatment response. Analyses of covariance, chi-squared tests, and binary logistic regressions were accomplished to determine differences in socio-demographic and clinical characteristics between MDD patients with and without pregabalin augmentation. Results: Add-on pregabalin was established in 102 (7.23%) MDD patients. Compared to those without receiving pregabalin, pregabalin-treated patients were characterized by a significantly higher likelihood for older age (mean: 54.74 +/- 13.08 vs 49.93 +/- 14.13 years), unemployment (78.43% vs 51.23%), melancholic features (83.33% vs 58.94%), inpatient treatment (72.55% vs 31.65%), previous psychiatric hospitalizations (13.52 +/- 24.82 vs 4.96 +/- 19.93 weeks), any somatic comorbidity (68.63% vs 44.57%), comorbid hypertension (37.25% vs 17.51%), more severe depressive symptom severity at the onset of the current episode (mean MADRS: 37.55 +/- 9.00 vs 33.79 +/- 7.52), receiving augmentation/combination treatment strategies in general (mean number of psychotropic drugs: 3.64 +/- 0.92 vs 2.07 +/- 1.17), and with antidepressants (50.00% vs 27.91%) and antipsychotics (46.08% vs 24.08%) in particular. Limitations: Due to its observational cross-sectional study design, our patient sample might not be fully representative for MDD patients in primary care settings. Conclusions: Our findings suggest that add-on pregabalin is particularly administered in more severe/difficult-totreat MDD conditions, whereas no association between the prescription of adjunctive pregabalin and comorbid anxiety symptoms could be determined.