Differential effects of treatments for chronic depression: a latent growth model reanalysis.
OBJECTIVE
Psychotherapy-pharmacotherapy combinations are frequently recommended for the treatment of chronic depressive disorders. Our aim in this novel reanalysis of archival data was to identify patient subgroups on the basis of symptom trajectories and examine the clinical significance of the resultant classification on basis of differential treatment effects to psychotherapy (cognitive behavioral analysis system of psychotherapy), pharmacotherapy (nefazodone), and their combination.


METHODS
We selected data for 504 patients diagnosed with chronic depression from archival data of a clinical trial (N = 681) and analyzed treatment courses (as assessed by the Hamilton Rating Scale for Depression) using growth mixture models, a contemporary exploratory analysis technique.


RESULTS
Three patient subgroups were identified from the typical patterns of change of depression severity during 12-week acute-phase treatment. Within these patient subgroups, differential treatment effects were evident: combination treatment clearly outperformed the 2 monotherapies in the largest patient subgroup, characterized by moderate depression severity, but not in the remaining 2 subgroups, characterized by low and severe depression at baseline. Patient characteristics prior to initiation of treatment enabled allocation of 61% of patients to these subgroups.


CONCLUSIONS
Research on patient subgroups with different change patterns may support classifications of patients that indicate which treatment is most effective for which type of patient.
Department of Psychiatry, University of Pennsylvania Philadelphia, PA 19104, USA. niklaus.stulz@gmail.com
Niklaus
N
Stulz
Michael E
ME
Thase
Daniel N
DN
Klein
Rachel
R
Manber
Paul
P
Crits-Christoph
D000328:Adult; D018687:Antidepressive Agents, Second-Generation / Q000009:adverse effects / Q000627:therapeutic use*; D002908:Chronic Disease; D015928:Cognitive Behavioral Therapy; D003131:Combined Modality Therapy; D003865:Major Depressive Disorder / Q000175:diagnosis / Q000523:psychology / Q000628:therapy*; D019263:Dysthymic Disorder / Q000175:diagnosis / Q000523:psychology / Q000628:therapy*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008960:Models, Psychological; D010555:Personality Inventory / Q000706:statistics & numerical data; D010879:Piperazines; D011594:Psychometrics; D055502:Secondary Prevention; D014230:Triazoles / Q000009:adverse effects / Q000627:therapeutic use*
D018687:Antidepressive Agents, Second-Generation; D010879:Piperazines; D014230:Triazoles; C051752:nefazodone