Serotonergic genes and suicidal ideation 2 weeks and 1 year after stroke in Korea

Objectives: Serotonergic genes are associated with suicidal behavior; this association has not been tested in stroke survivors, however. In this study, we investigated whether serotonin transporter (5-HTT) and serotonin 2a receptor (5-HTR2a) genes were associated with suicidal ideation at 2 weeks and at 1 year after stroke.

Methods: A total of 286 patients were evaluated 2 weeks after stroke, and 222 (78%) participated in a follow-up evaluation one year later. Suicidal ideation was ascertained using the "suicidal thoughts" item of the Montgomery and Asberg Depression Rating Scale. Associations between suicidal ideation and 5-HTTLPR, STin2 VNTR, 5-HTR2a 1438A/G, and 5-HTR2a 102T/C genotypes were estimated using logistic regression models, and gene-gene interactions were investigated using the generalized multifactor dimensionality reduction method after adjustment for potential covariates, including depression.

Results: The 5-HTR2a 1438 A/A genotype was significantly associated with suicidal ideation 2 weeks after stroke, before and after statistical adjustment. The 5-HTTLPR short allele was associated with suicidal ideation 2 weeks after stroke, although the significance of this finding was not evident after adjustment. No significant associations were observed between any genotype and suicidal ideation one year after stroke. No significant gene-gene interactions were detected.

Conclusions: Individuals with the 5-HTR2a 1438 A/A genotype were more susceptible to suicidal ideation 2 weeks after stroke. Careful evaluation and management are indicated for those with increased genetic vulnerability, particularly during the acute phase of stroke.