The onset of antidepressant action is vital clinically. This study aimed to testify whether early symptom improvement can predict eventual treatment response at week 6 among depressive hospitalized patients taking fluoxetine. One hundred thirty-one hospitalized patients with major depressive disorder received 20 mg/d of fluoxetine for 6 weeks. Symptom severity was assessed by the 17-item Hamilton Depression Rating Scale (HAMD-17) at weeks 0, 1, 2, 3, 4, and 6. Stable response was defined as a reduction of 50% or more in the HAMD-17 total score at weeks 4 and 6 of treatment. Receiver operating characteristic curve was used to determine the cutoff point of the percentage of HAMD-17 score reduction between stable responders and nonresponders at weeks 1, 2, 3, and 4. At weeks 1, 2, 3, and 4, HAMD-17 score reductions of 25%, 39%, 43%, and 50% seemed to be the optimal cutoff points for predicting eventual response. They provided a sensitivity of 78%, 86%, 91%, and 93% and a specificity of 61%, 74%, 76%, and 92%. The percentage of HAMD-17 reduction at week 4 excellently predicted final response at week 6. Patients with less than a 50% symptom reduction during the first 4 weeks of treatment are unlikely to reach a final stable response. Whether this model can be applied to establish a prediction system for other antidepressants or for outpatients warrants further research.
From the *Kai-Suan Psychiatric Hospital, Kaohsiung; †Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung; ‡Institute of Clinical Medical Science and §Department of Psychiatry, China Medical University Hospital, Taichung; and ∥Department of Medical Research, Kaohsiung Medical University Hospital, ¶Department of Medical Genetics, College of Medicine, #Center of Excellence for Environmental Medicine, **Department of Psychiatry, Faculty of Medicine, College of Medicine, and ††Department of Psychiatry, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan.
Received June 5, 2010; accepted after revision January 14, 2011.
Reprints: Cheng-Fang Yen, MD, PhD, Department of Psychiatry, Kaohsiung Medical University Hospital, 100 Tzyou 1st Rd, Kaohsiung City, Taiwan 807 (e-mail: email@example.com).
This study was funded by the Kai-Suan Psychiatric Hospital in 2007-2009, and National Science Council, Taiwan (NSC-97-2314-B-039-006-MY3 and NSC-98-2627-B-039-001), National Health Research Institutes, Taiwan (NHRI-EX-100-9904NI), Taiwan Department of Health Clinical Trial, and Research Center of Excellence (DOH100-TD-B-111-004).