Serotonin transporter polymorphisms and the occurrence of adverse events during treatment with selective serotonin reuptake inhibitors.

During treatment with selective serotonin reuptake inhibitors, some patients experience adverse events whereas others do not. Assessment of predictors for selective serotonin reuptake inhibitors-induced adverse events would be useful for the identification of patients likely to develop these events. This study evaluates the association between adverse events during selective serotonin reuptake inhibitor treatment and two polymorphisms in the serotonin transporter (5-HTTLPR and STin2) gene. We included 214 patients meeting Diagnostic and statistical manual of mental disorder-IV criteria for major depression and using an selective serotonin reuptake inhibitor for at least 6 weeks. Blood samples or buccal swabs were taken to determine 5-HTTLPR and STin2 genotype. Information on adverse events was gathered through interviews and general practitioners' files. The association between serotonin transporter genotype and adverse events was assessed by use of logistic regression. Patients with the 5-HTTLPR s/s or s/l genotype appeared to have an increased risk of adverse events, especially general adverse events (dermatologic reactions, weight change and fatigue); odds ratio 1.77 (95% confidence interval 0.80-3.92) for the s/s genotype, odds ratio 2.37 (95% confidence interval 1.13-4.96) for the s/l genotype. For STin2, results were inconsistent and observed associations were weak and statistically nonsignificant. Our findings indicate that patients with the 5-HTTLPR s/s or s/l genotype have an increased risk of developing adverse events during selective serotonin reuptake inhibitor treatment.