Polimorfismo genético da apolipoproteína E e avaliação sociodemográfica em pacientes com periodontite crônica

Abstract

Chronic periodontitis (CP) is characterized by an inflammation in the supporting tissues of the teeth. It is primarily caused by bacteria, but progression is associated with individual host response. CP is a complex and multifactorial disease. Genetic and environmental factors interacting can modify the clinical cause of the disease. Genetic polymorphisms have been studied to identify possible genetic markers and explain differences in the inflammatory cytokines expression. Apolipoprotein E (apoE) is an important protein in lipid metabolism and is also envolved in pathophysiological processes. The aim of this study was to investigate whether there is an association of the APOE polymorphisms with the CP´s susceptibility in subjects that sought periodontal treatment at Dental School of Federal University of Ceara and evaluate sociodemographic status related with the disease. A sample of 109 subjects between 30 and 70 years (mean age = 44,5 ± 9,64) were grouped into: 53 controls and 56 subjects with CP. DNA was obtained through a mouthwash and oral mucosa scraping and genotyped by PCR-RFLP method (Polimerase Chain Reaction – Restrict Fragment Length Polymorphism). Differences in the allele and genotype frequencies were assessed by Chi-squared test (p˂0.05). The risk associated with alleles and genotypes was calculated as odds ratio (OR) with 95% confidence intervals (CI). Logistic regression was used to associate sociodemographic status with CP and genotypes. No differences were observed in the apoE allelic distribution regarding control and periodontitis groups. Age and socio-economic status increase the risk for having CP, since individuals with lower socio-economic status was about 3-fold more likely to develop periodontitis (OR=3.1) and increase in age enhances the risk in 5.1% to develop disease in each year of age. Hypertension was a factor of clinic importance in development of CP, since subjects who self-reported hypertensive have 2,5-fold more likely to develop disease than individuals who not self-reported hypertension, although no statistic difference was reached. Similarly, CP was also associated with lower education level (OR=3.7). The polymorphism in the APOE gene was not associated with the susceptibility to CP in the studied population.