title: Predicting relapse in major depressive disorder using patient-reported outcomes of depressive symptom severity, functioning, and quality of life in the Individual Burden of Illness Index for Depression (IBI-D).
abstract: BACKGROUND
  Patients with Major Depressive Disorder (MDD) often experience unexpected relapses, despite achieving remission. This study examines the utility of a single multidimensional measure that captures variance in patient-reported Depressive Symptom Severity, Functioning, and Quality of Life (QOL), in predicting MDD relapse.
  
  
  METHODS
  Complete data from remitted patients at the completion of 12 weeks of citalopram in the STAR*D study were used to calculate the Individual Burden of Illness index for Depression (IBI-D), and predict subsequent relapse at six (n=956), nine (n=778), and twelve months (n=479) using generalized linear models.
  
  
  RESULTS
  Depressive Symptom Severity, Functioning, and QOL were all predictors of subsequent relapse. Using Akaike information criteria (AIC), the IBI-D provided a good model for relapse even when Depressive Symptom Severity, Functioning, and QOL were combined in a single model. Specifically, an increase of one in the IBI-D increased the odds ratio of relapse by 2.5 at 6 months (β=0.921 ± 0.194, z=4.76, p<2 × 10(-6)), by 2.84 at 9 months (β=1.045 ± 0.22, z=4.74, p<2.2 × 10(-6)), and by 4.1 at 12 months (β=1.41 ± 0.29, z=4.79, p<1.7 × 10(-6)).
  
  
  CONCLUSIONS
  Self-report poses a risk to measurement precision. Using highly valid and reliable measures could mitigate this risk. The IBI-D requires time and effort for filling out the scales and index calculation. Technological solutions could help ease these burdens. The sample suffered from attrition. Separate analysis of dropouts would be helpful.
  
  
  CONCLUSIONS
  Incorporating patient-reported outcomes of Functioning and QOL in addition to Depressive Symptom Severity in the IBI-D is useful in assessing the full burden of illness and in adequately predicting relapse, in MDD.
authors.affiliation: Department of Psychiatry and Behavioral Neurosciences, Cedars-Sinai Medical Center, Los Angeles, Los Angeles, CA, USA. Waguih.IsHak@cshs.org
authors.forename: Waguih William
authors.initials: WW
authors.lastname: Ishak
authors.forename: Jared M
authors.initials: JM
authors.lastname: Greenberg
authors.forename: Robert M
authors.initials: RM
authors.lastname: Cohen
mesh_terms: D000203:Activities of Daily Living / Q000523:psychology; D000328:Adult; D018687:Antidepressive Agents, Second-Generation / Q000627:therapeutic use; D015283:Citalopram / Q000627:therapeutic use; D017281:Cost of Illness; D003865:Major Depressive Disorder / Q000175:diagnosis* / Q000188:drug therapy / Q000453:epidemiology / Q000523:psychology; D005260:Female; D006801:Humans; D008297:Male; D011569:Psychiatric Status Rating Scales; D011788:Quality of Life / Q000523:psychology*; D012008:Recurrence; D012074:Remission Induction; D012307:Risk Factors; D057566:Self Report
chemical_list: D018687:Antidepressive Agents, Second-Generation; D015283:Citalopram
keywords: Burden of illness; Functioning; Major depressive disorder; Mood disorders; Quality of life; STAR*D