Allelic variation, in the serotonin transporter promoter affects onset of paroxetine treatment response in late-life depression

The relationship of the serotonin transporter gene promoter region polymorp hism (5-HTTLPR) to antidepressant response was examined in 95 elderly patie nts receiving a protocolized treatment for depression with paroxetine or no rtriptyline. Patients were treated for up to 12 weeks and assessed weekly w ith clinical ratings and measurements of plasma drug concentrations. Twenty -one of the paroxetine treated subjects were found to have the 11 genotype and 30 had at least one s allele. There were no baseline differences betwee n these groups in pretreatment Hamilton Rating Scale for Depression (HRSD) scores or anxiety symptoms. During acute treatment with paroxetine, mean re ductions from baseline in HRSD were significantly move rapid for patients w ith the 11 genotype than for those possessing an s allele, despite equivale nt paroxetine concentrations. Onset of response to nortriptyline was not af fected. Allelic variation of 5-HTTLPR may contribute to the variable initia l response of patients treated with a selective serotonin reuptake inhibito r. (C) 2000 American College of Neuropsychopharmacology. Published by Elsev ier Science Inc.