Psychosocial state after bariatric surgery is associated with the serotonin-transporter promoter polymorphism

Bariatric surgery is the method of choice in the treatment of morbid obesity. Different genotypes of the serotonin transporter gene (5-HTT) are known to impact the prevalence of psychiatric disorders and the psychosocial state in obese individuals. In this study, we examined the influence of the 5-HTTLPR polymorphism on physiologic and psychosocial measures in morbidly obese women after bariatric surgery.

We investigated women 1-5 years after bariatric surgery using a semi-structured interview and the Beck Depression Inventory, the Moorhead-Ardelt Quality of life questionnaire, the NEO-Five Factor Inventory and a Resilience scale. The 5-HTTLPR polymorphism (s/s, s/l, l/l) was genotyped using mouth swabs. The influence of genotype on outcome variables was analyzed by independent t test and analysis of covariance corrected for possible confounders.

64 women were enrolled in this study between January 2004 and September 2009. Significantly lower quality of life and higher depression, neuroticism and resilience scores were found in homozygous s-allele carriers of the 5-HTTLPR polymorphism than in l-allele carriers. Except for neuroticism, other factors (age, education, year of surgery, weight before surgery and method of surgery) did not affect the results. We found no influence of genotype on weight loss, current weight or weight before surgery.

Quality of life, mood, and resilience but not weight loss after bariatric surgery are negatively influenced by the s-allele of the 5-HTTLPR polymorphism.