Associations of serotonergic genes with poststroke emotional incontinence

Poststroke emotional incontinence (PSEI) has been associated with serotonergic dysfunction. Polymorphisms of serotonin transporter (5-HTT) and serotonin 2a receptor (5-HTR2a) genes may regulate serotonergic signaling at brain synapses, and this study was to investigate associations with PSEI in an East Asian population.

In 276 stroke cases, PSEI was diagnosed by Kim's criteria. Covariates included age, gender, education, history of depression or stroke, current depression, and stroke severity and location. Genotypes were ascertained for 5-HTT gene-linked promoter region (5-HTTLPR), serotonin transporter intron 2 variable number tandem repeat, 5-HTR2a 1438A/G, and 5-HTR2a 102 T/C. Associations with PSEI were estimated by using logistic regression models, and gene-gene interactions were investigated by using the generalized multifactor dimensionality reduction method.

PSEI was present in 37 (13.4%) patients. The 5-HTT gene-linked promoter region s/s genotype was independently associated with PSEI. No associations with STin2 VNTR and 5-HTR2a genes were found, and no significant gene-gene interactions were identified.

Stroke patients with 5-HTTLPR s allele had higher susceptibility to PSEI, which underlines the potential role of serotonergic pathways in its etiology.