Neurocognitive predictors of antidepressant clinical response
Gerard E. Bruder a,b, Jorge E. Alvarenga b, Daniel Alschuler b, Karen Abraham b, John G. Keilp a,c, David J. Hellerstein a,d, Jonathan W. Stewart a,d, Patrick J. McGrath a,d
a Department of Psychiatry, Columbia University College of Physicians & Surgeons, New York, NY, USA;
b Division of Cognitive Neuroscience, New York State Psychiatric Institute, New York, NY, USA;
c Division of Molecular Imaging & Neuropathology, New York State Psychiatric Institute, New York, NY, USA;
d Depression Evaluation Service, New York State Psychiatric Institute, New York, NY, USA
Received 18 December 2013; revised 24 April 2014; accepted 25 April 2014; published online 4 May 2014.
Abstract Background: Executive dysfunction and psychomotor slowing in depressed patients have been associated with poor antidepressant clinical response, but little is known about the value of neurocognitive tests for differential prediction of response. Methods: This report presents new findings for 70 depressed patients tested on neurocogntive tests before receiving treatment with a SSRI (escitalopram or citalopram), NDRI (bupropion) or dual mechanism therapy including a serotonergic agent, and for 57 healthy controls. Results: As predicted from previous research, patients who did not respond to a SSRI or dual therapy showed poorer word fluency than responders, whereas this was not seen for patients treated with bupropion alone. Longer choice reaction time (RT) was also found in nonresponders to a SSRI or dual therapy, but the opposite trend was seen for bupropion. Using a combined index of word fluency and RT (with normative performance as a cutoff) yielded differential predictions of response. Equal to or above normal performance predicted good response to a SSRI or dual therapy, with high positive predictive value (90%) and specificity (78%) but lower sensitivity (53%). In contrast, less than normal performance predicted good response to bupropion alone (positive predictive value = 82%; specificity = 67%; sensitivity = 90%). Limitations: Relatively small sample size, no placebo control, and combining across SSRI alone and dual treatments. Conclusions: Although findings are preliminary due to small sample size, brief tests of word fluency and psychomotor speed may help identify depressed patients who are unresponsive to a serotonergic agent, but who may respond to bupropion alone. Keywords: Depression; Antidepressants; Treatment response; Neurocognitive tests; Psychomotor speed |