Effect of COMT Val158Met Polymorphism on Stroke Functional Outcome and Recovery

Background. A single nucleotide polymorphism (SNP) in the catechol-o-methyltransferase (COMT) gene, Val158Met (rs4680), influences cognition in the general population. However, its role in stroke recovery is unclear. In this study, we evaluated the association of Val158Met SNP with stroke functional outcome and recovery. Methods. This is a retrospective study. The MGB Biobank was queried for 570 individuals with stroke and available genomics data. A subset of 164 was curated based on their admission to Spaulding Rehabilitation Hospital (SRH) for inpatient rehabilitation, meeting inclusion/exclusion criteria and receiving a rehabilitation program tailored to their individual needs and goals. Functional independent measures (FIM) were assessed upon admission to SRH and discharge. Multiple tests were performed to identify related clinic characteristics associated with functional outcome, recovery, and independence dichotomization. Logistic and linear regression models adjusted for covariate variables were used to evaluate the association between COMT Val58Met and functional outcome and recovery. Results. Genotype analysis confirmed that COMT Met/Met frequency was higher compared to Val allele frequency in high cognitive functional outcome. Furthermore, after adjusting for covariate variables, COMT Met/Met led to positive cognitive outcome (P = 0.029; OR = 2.43 [0.19-4.56)] in comprehension (P = 0.013, OR = 0.62 [0.15-1.08]) and expression (P = 0.007, OR = 0.74 [0.19-1.25]). In independence dichotomization analysis, high cognitive outcomes (P = 0.04, OR = 0.81 [1.04-4.82]) were found in the sub-domains of comprehension (P = 0.002, OR = 1.21 [1.56-7.17]), expression (P = 0.03, OR = 0.83 [1.08-4.83]), problem solving (P = 0.02, OR = 0.88 [1.15-5.06]), and memory (P = 0.039, OR = 0.78 [1.04-4.58]). Conclusion. Stroke patients with COMT Met/Met were associated with improved cognition, comprehension, and expression functional outcomes..