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Evaluation of quantitative EEG by classification and regression trees to characterize responders to antidepressant and placebo treatment.

Rabinoff M, Kitchen CM, Cook IA, Leuchter AF - Open Med Inform J (2011)

Bottom Line: For those receiving venlafaxine, CART identified a decrease in δ absolute power at day 7 at the PO2 region as characterizing treatment responders (p=0.01).Using all patients receiving medication, CART identified a decrease in δ absolute power at day 2 in the FP1 region as characteristic of nonresponse to medication (p=0.003).The results of our study suggest that CART may be a useful method for identifying potential outcome predictors in the treatment of major depression.

View Article: PubMed Central - PubMed

Affiliation: Department of Psychiatry and Biobehavioral Sciences, University of California, Los Angeles, CA, USA.

ABSTRACT
The study objective was to evaluate the usefulness of Classification and Regression Trees (CART), to classify clinical responders to antidepressant and placebo treatment, utilizing symptom severity and quantitative EEG (QEEG) data. Patients included 51 adults with unipolar depression who completed treatment trials using either fluoxetine, venlafaxine or placebo. Hamilton Depression Rating Scale (HAM-D) and single electrodes data were recorded at baseline, 2, 7, 14, 28 and 56 days. Patients were classified as medication and placebo responders or non-responders. CART analysis of HAM-D scores showed that patients with HAM-D scores lower than 13 by day 7 were more likely to be treatment responders to fluoxetine or venlafaxine compared to non-responders (p=0.001). Youden's index γ revealed that CART models using QEEG measures were more accurate than HAM-D-based models. For patients given fluoxetine, patients with a decrease at day 2 in θ cordance at AF2 were classified by CART as treatment responders (p=0.02). For those receiving venlafaxine, CART identified a decrease in δ absolute power at day 7 at the PO2 region as characterizing treatment responders (p=0.01). Using all patients receiving medication, CART identified a decrease in δ absolute power at day 2 in the FP1 region as characteristic of nonresponse to medication (p=0.003). Optimal trees from the QEEG CART analysis primarily utilized cordance values, but also incorporated some δ absolute power values. The results of our study suggest that CART may be a useful method for identifying potential outcome predictors in the treatment of major depression.

No MeSH data available.


Related in: MedlinePlus

Experimental Protocol Timeline. Subjects were assessed and enrolled at “intake”, had the pretreatment baseline EEG recorded at that time, and then participated in a one week, single-blind placebo lead-in phase. Randomization to treatment modality (active medication or placebo) took place at the time marked “start of treatment”, Another EEG was recorded after 48 hours of treatment and again at 1 week. Clinical assessment to determine outcome (responder vs non-responder) took place after 8 weeks of treatment (9 weeks in study altogether). Subjects were monitored weekly during the double-blind treatment (arrows not shown) for clinical changes and adverse reactions [10].
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Figure 1: Experimental Protocol Timeline. Subjects were assessed and enrolled at “intake”, had the pretreatment baseline EEG recorded at that time, and then participated in a one week, single-blind placebo lead-in phase. Randomization to treatment modality (active medication or placebo) took place at the time marked “start of treatment”, Another EEG was recorded after 48 hours of treatment and again at 1 week. Clinical assessment to determine outcome (responder vs non-responder) took place after 8 weeks of treatment (9 weeks in study altogether). Subjects were monitored weekly during the double-blind treatment (arrows not shown) for clinical changes and adverse reactions [10].

Mentions: QEEG recordings were obtained (a) at pretreatment baseline prior to randomization, (b) at 48 hours (after two doses of drug or placebo), and (c) after 1 week on medication or placebo, as shown in Fig. (1). Recordings were made with the QND System (Neurodata, Inc., Pasadena, CA), using procedures employed in our previous reports and summarized here. Patients were instructed to rest in the eyes-closed, maximally alert state, in a quiet room with subdued lighting. The technicians monitored the QEEG data in real-time during the recording, and re-alerted the patients every 30-45 seconds as needed to avoid drowsiness. Electrodes were placed with an electrode cap (ElectroCap, Eaton, OH) using 35 recording electrodes distributed across the head according to the International 10-20 System arrangement (Fig. 2). Data were collected using a Pz referential montage and were digitized at 256 samples/channel/sec by the QND system (bandpass filtered 0.3 - 70 Hz).


Evaluation of quantitative EEG by classification and regression trees to characterize responders to antidepressant and placebo treatment.

Rabinoff M, Kitchen CM, Cook IA, Leuchter AF - Open Med Inform J (2011)

Experimental Protocol Timeline. Subjects were assessed and enrolled at “intake”, had the pretreatment baseline EEG recorded at that time, and then participated in a one week, single-blind placebo lead-in phase. Randomization to treatment modality (active medication or placebo) took place at the time marked “start of treatment”, Another EEG was recorded after 48 hours of treatment and again at 1 week. Clinical assessment to determine outcome (responder vs non-responder) took place after 8 weeks of treatment (9 weeks in study altogether). Subjects were monitored weekly during the double-blind treatment (arrows not shown) for clinical changes and adverse reactions [10].
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3097432&req=5

Figure 1: Experimental Protocol Timeline. Subjects were assessed and enrolled at “intake”, had the pretreatment baseline EEG recorded at that time, and then participated in a one week, single-blind placebo lead-in phase. Randomization to treatment modality (active medication or placebo) took place at the time marked “start of treatment”, Another EEG was recorded after 48 hours of treatment and again at 1 week. Clinical assessment to determine outcome (responder vs non-responder) took place after 8 weeks of treatment (9 weeks in study altogether). Subjects were monitored weekly during the double-blind treatment (arrows not shown) for clinical changes and adverse reactions [10].
Mentions: QEEG recordings were obtained (a) at pretreatment baseline prior to randomization, (b) at 48 hours (after two doses of drug or placebo), and (c) after 1 week on medication or placebo, as shown in Fig. (1). Recordings were made with the QND System (Neurodata, Inc., Pasadena, CA), using procedures employed in our previous reports and summarized here. Patients were instructed to rest in the eyes-closed, maximally alert state, in a quiet room with subdued lighting. The technicians monitored the QEEG data in real-time during the recording, and re-alerted the patients every 30-45 seconds as needed to avoid drowsiness. Electrodes were placed with an electrode cap (ElectroCap, Eaton, OH) using 35 recording electrodes distributed across the head according to the International 10-20 System arrangement (Fig. 2). Data were collected using a Pz referential montage and were digitized at 256 samples/channel/sec by the QND system (bandpass filtered 0.3 - 70 Hz).

Bottom Line: For those receiving venlafaxine, CART identified a decrease in δ absolute power at day 7 at the PO2 region as characterizing treatment responders (p=0.01).Using all patients receiving medication, CART identified a decrease in δ absolute power at day 2 in the FP1 region as characteristic of nonresponse to medication (p=0.003).The results of our study suggest that CART may be a useful method for identifying potential outcome predictors in the treatment of major depression.

View Article: PubMed Central - PubMed

Affiliation: Department of Psychiatry and Biobehavioral Sciences, University of California, Los Angeles, CA, USA.

ABSTRACT
The study objective was to evaluate the usefulness of Classification and Regression Trees (CART), to classify clinical responders to antidepressant and placebo treatment, utilizing symptom severity and quantitative EEG (QEEG) data. Patients included 51 adults with unipolar depression who completed treatment trials using either fluoxetine, venlafaxine or placebo. Hamilton Depression Rating Scale (HAM-D) and single electrodes data were recorded at baseline, 2, 7, 14, 28 and 56 days. Patients were classified as medication and placebo responders or non-responders. CART analysis of HAM-D scores showed that patients with HAM-D scores lower than 13 by day 7 were more likely to be treatment responders to fluoxetine or venlafaxine compared to non-responders (p=0.001). Youden's index γ revealed that CART models using QEEG measures were more accurate than HAM-D-based models. For patients given fluoxetine, patients with a decrease at day 2 in θ cordance at AF2 were classified by CART as treatment responders (p=0.02). For those receiving venlafaxine, CART identified a decrease in δ absolute power at day 7 at the PO2 region as characterizing treatment responders (p=0.01). Using all patients receiving medication, CART identified a decrease in δ absolute power at day 2 in the FP1 region as characteristic of nonresponse to medication (p=0.003). Optimal trees from the QEEG CART analysis primarily utilized cordance values, but also incorporated some δ absolute power values. The results of our study suggest that CART may be a useful method for identifying potential outcome predictors in the treatment of major depression.

No MeSH data available.


Related in: MedlinePlus