RESUMO
OBJECTIVE: Our aim was to identify the role of PvuII and XbaI polymorphisms of the ESR1 (estrogen receptor alpha) gene in the occurrence of early restenosis after carotid endarterectomy and carotid artery stenting. METHODS: In a non-randomized prospective study we analysed blood samples from 172 patients (105 men) with severe stenosis of the internal carotid artery, using the PCR-RFLP method. Patients were treated either by carotid endarterectomy (n=82) or carotid artery stenting (n=90), and were followed-up by ultrasonography with a median follow-up time of 12 months (7.32-14.65 months). Conventional laboratory parameters were also recorded. Restenosis (>50%) rates were compared between patients carrying different genotypes and risk factors were calculated by using multivariate logistic regression. RESULTS: Allelic frequencies were similar between sexes (C/T allele, 0.40/0.60 and 0.43/0.57; p=0.67; G/A allele, 0.35/0.65 and 0.32/0.68; p=0.65; in men and women, respectively). Significantly higher restenosis rate was observed in patients homozygous for the A-allele of the XbaI polymorphism as compared to carriers of AG and GG genotypes (23.4% vs. 10.5%, p=0.02). TT and TC genotypes of the PvuII polymorphism were also associated with greater restenosis rate, as compared with genotype CC (19.3% vs. 3.1%, p=0.02). Associations for both polymorphisms were more expressed in women and in CEA patients. At multivariate analysis, T-A haplotype was a predictor of restenosis in the whole patient cohort (adjusted odds ratio, 7.85; 95% CI, 1.01-60.98). CONCLUSION: Presence of A and T alleles (of the XbaI and PvuII polymorphisms, respectively) were associated with higher incidence of carotid restenosis, while the presence of G and C alleles (of the XbaI and PvuII polymorphisms, respectively) were associated with lower incidence of carotid restenosis.