Abrupt and brief discontinuation of antidepressant treatment: effects on cognitive function and psychomotor performance

Abstract

The abrupt discontinuation of antidepressants can result in a syndrome of adverse events, including somatic, mood and psychomotor reactions. This study examined the effects of discontinuing and resuming antidepressant treatment with four selective serotonin reuptake inhibitors (SSRIs) on cognitive and psychomotor function. Eighty-seven patients receiving maintenance therapy with fluoxetine, sertraline, paroxetine or citalopram had their treatment interrupted for 4-7 days using double-blind placebo. Assessments of aspects of cognitive and psychomotor performance, mood and symptoms were carried out at each visit. Following interruption of treatment, significant differences between the groups emerged. Paroxetine treated patients experienced significantly more cognitive failures (P = 0.007), poorer quality of sleep (P = 0.016), and an increase in depressive symptoms, as rated both subjectively, using the Zung scale (P = 0.006) and by the clinician, using the Montgomery-Asberg Depression Rating Scale (P = 0.0003) and Clinical Global Impression (P = 0.0003), compared to some or all of the other drugs. All changes were reversed on reinstatement of treatment. Abrupt discontinuation of treatment with paroxetine leads to deterioration in various aspects of health and functioning, which may be related to the antidepressant discontinuation syndrome. These effects are not evident in patients receiving fluoxetine, sertraline and citalopram, suggesting they are not an SSRI class phenomenon.