Effects of sertraline on autonomic and cognitive functions in healthy volunteers

Rationale. Though sertraline, a selective serotonin reuptake inhibitor (SSRI), causes autonomic and cognitive adverse events such as dry mouth and somnolence, there is a paucity of appropriately designed studies on the cognitive and autonomic effects of the drug in the literature. Objective. To compare the effects of sertraline on cognitive and autonomic functions with those of placebo in healthy humans. Method. A randomized, double blind, cross over study of 12 healthy male volunteers aged 24 (21- 32; median; range) years. Subjects orally received 50 mg sertraline and placebo once daily for periods of 14 days each with at least 14 days in between. Heart rate variability (HRV), skin conductance level (SCL) and skin conductance response (SCR) following sudden deep respiration were employed as parameters for autonomic function. Quantitative EEG (qEEG) and psychometric tests served as parameters for cognitive function. Measurements were performed repeatedly before the start of drug administration and on the last treatment day. Results. Sertraline caused a significant reduction of heart rate and SCL (P<0.05), whereas HRV and SCR were not changed. Cognitive functions such as flicker fusion frequency, memory, choice reaction time and psychomotor performance were not influenced by sertraline but slow and fast beta power density in the qEEG was increased. Conclusion. Cognitive and psychomotor performance are not altered in healthy humans receiving multiple dosing with sertraline. The observed decreases in heart rate and SCL may be due to a sympatho-inhibitory effect of sertraline.