RESUMO
BACKGROUND AND OBJECTIVES: Some experimental studies demonstrated adverse modulation of atherothrombosis by interleukin-1beta (IL-1b). To assess the relationship between the five most common variants of three polymorphisms of the IL1b gene cluster and the complexity of coronary atherosclerosis expressed in Gensini Score (GS), and the age of onset of the first acute coronary syndrome (ACS), we assessed the patients (pts) hospitalized due to ACS in this aspect. MATERIALS AND METHODS: 250 individuals were included. The single nucleotide polymorphisms of IL1b gene: transition T/C at -31 position, C/T at -511, and those of IL1 receptor antagonist gene (IL1RN)-variable number of tandem repeats allele 1, 2, 3, or 4-were determined by PCR. GS was calculated from the coronary angiogram performed at the index ACS. The impact of the presence of T or C and allele 1 to 4 at the investigated loci on the mean GS, GS greater than 40, mean age of onset of ACS, and the fraction of pts over 60 years of age at ACS were compared between the five most common genotype variants. RESULTS: The five most common variants were present in 203 pts (81.2%). Patients with pair 22 in ILRN had the lowest rate and those with pair 12 had the highest rate of ACS before 60 years of age (29.4 vs. 67.8%; p = 0.004). GS > 40 entailed an eight-fold increase of risk, as observed when pts with one T allele at locus -31 were compared with carriers of 2 or no T allele at this locus: OR 8.73 [CI95 4.26-70.99] p = 0.04. CONCLUSION: Interleukin-1 beta is subject to frequent genetic variability and our results show a potential relationship of this polymorphism with the extent of coronary atherosclerosis and age at the first ACS.
RESUMO
INTRODUCTION: The endothelium and sympathetic nervous system play an important role in the pathogenesis of acute coronary syndrome (ACS). OBJECTIVES: The aim of our study was to evaluate correlations between noninvasive markers of the endothelial function and the sympathetic nervous system in patients with a recent ACS. PATIENTS AND METHODS: The study included 52 patients who experienced an ACS within the previous 3 to 6 months. Endothelial function was expressed as the reactive hyperemia index (RHI), and the activity of the sympathetic nervous system--as latency and amplitude of sympathetic skin response (SSR) potentials from the 4 limbs. Linear and partial correlations between the RHI and SSR were calculated. RESULTS: There were significant correlations between the RHI and the latency of the SSR in the upper limbs (r = 0.34, P = 0.02 for the right limb; and r = 0.34, P = 0.01 for the left limb). After eliminating the effects of age, sex, weight, and glomerular filtration rate, the partial correlation between the RHI and the latency of the SSR in the upper limbs remained statistically significant (r = 0.41, P = 0.004 for the right limb, and r = 0.42, P = 0.004 for the left limb). There was no correlation between the RHI and latency of the SSR during the stimulation of the lower limbs. CONCLUSIONS: Our study confirmed the correlations between the sympathetic autonomic nervous system and endothelium in patients with ACS. The correlation of the RHI with the latency of the SSR was observed only in the upper limbs.
