The specificity of neuropsychological impairment in predicting antidepressant non-response in the very old depressed.

Objective In an earlier report, response inhibition predict antidepressant non-response in late-life depression (Sneed et al., <BIBR>2007</BIBR>). The purpose of this study was to ascertain whether this effect is specific to response inhibition or whether impairment in other cognitive domains also predicts non-response. Method Older depressed patients (n = 84) enrolled in an 8-week trial of citalopram were classified as impaired or non-impaired relative to the sample on mental status, psychomotor speed, reaction time, spatial judgment, and memory, and contrasted with regard to antidepressant response. Results Patients who were impaired relative to the sample on digit symbol performance did not respond as quickly to citalopram as those who were unimpaired. By the end of the 8-week trial, however, both groups reached the same level of response. Impairment in other domains had no impact on antidepressant response. Conclusions Non-response was not attributable to impairment on any of the neuropsychological tests suggesting that antidepressant non-response is specific to impaired response inhibition. Copyright © 2007 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]