IJCS | Volume 33, Nº3, May / June 2020

257 Silva et al. Polymorphisms in acute coronary syndrome Int J Cardiovasc Sci. 2020; 33(3):254-262 Original Article Table 2 – Distribution of genotypic frequencies of SNPs in the IL8 and IL16 genes in the three groups Genotype ACS (N = 200) NON-ACS (N = 50) SCA x NON-ACS DONORS (N = 220) ACS x DONORS N % N % p N % p IL8 (rs4073) AA 46 23 8 16 0.46 61 27.8 0.31 AT 99 49.5 29 58 111 50.4 TT 55 27.5 13 26 48 21.5 AT+TT 154 77 42 84 0.36 159 72.3 0.31 Alleles A 191 45 233 T 209 55 207 IL16 (rs11556218) TT 154 77 33 66 0.30 141 64 0.0026 TG 42 21 16 32 78 35.5 GG 4 2 1 2 1 0.5 TG + GG 46 23 17 34 0.17 79 36 0.0052 Alleles G 50 18 80 T 350 82 283 N: number of patients; p: Williams-G test; SNP: single-nucleotide polymorphism; ACS: acute coronary syndrome. (TG = 10), (GG = 1) and 20 samples fromdonor individuals (TT = 9), (TG = 10) and (GG = 1) were used. The dosages of IL-16 were similar among the three different genotypes in patients with ACS (Figure 1B). In the donor individuals, the G (TG + GG) allele had higher serum IL-16 levels (701.9 pg/mL) than those with TT genotype (447.7 pg/mL) (p = 0.001) (Figure 1 A). The dosage of this cytokine was higher in the donor group (563.0 pg/mL) than in patients withACS (355.4 pg/ mL) (p = 0.04) (Figure 1C). The genotypic frequencies of blood donors were also compared to other healthy populations (Table 4). The results show that for the IL8 gene there was similarity (p > 0.05) in the genotypic distribution between the present study and other Brazilian populations of Maranhão 20 and São Paulo 21 and the populations of Iran 22 and Greece. 9 Regarding SNP rs11556218 in the IL16 gene, there was a difference between the genotype frequencies of China 23 and Iran 24 when compared to the present study (p = 0.01 and < 0.0001, respectively). Discussion The age presents itself as one of the most important risk factors for ACS. 28 According to Dutra et al., 29 cardiovascular diseases affect mostly elderly individuals. The mean age found in the present study was 62 years old, corroborating the data obtained by Marino et al., 30 in a study performed with Brazilian patients with ACS who found a mean age of 63 years old and by Shah et al., 31 studying Scottish patients with ACS with a mean age of 62 years old.