Association Between Interleukin-6 -572 C>G and -174 G>C Polymorphisms and Hypertension: A Meta-analysis of Case-control Studies

Evaluation the -174G>C Genetic Polymorphism of Interleukin-6 in Iranian Patients with Chronic Lymphocytic Leukemia

Background & Objective

Interleukin-6 (IL-6) is involved in inflammation and has a significant role in chronic lymphocytic leukemia (CLL) progression. Accordingly, IL-6 level may increase in CLL-affected patients compared to healthy individuals. The -174G>C single nucleotide polymorphism (SNP) in IL-6 promoter region has been related to differences in IL-6 transcription. Therefore, we investigated the possible association of IL-6 polymorphism with CLL.

Methods

We examined the -174G>C SNP in IL-6 gene and studied its possible relationship with CLL in affected patients and in healthy controls using Amplification Refractory Mutation System- polymerase chain reaction genotyping method. IL-6 plasma level was measured in both studied groups.

Results

According to the results, IL-6 mean plasma concentration was increased significantly in the CLL patients compared to the controls. However, 174G>C genotype of the IL-6 gene was not associated with CLL. Furthermore, there were no significant differences in the distribution of allele and genotype frequencies between the CLL-affected patients and the controls (P>0.05).

Conclusion

Our study showed that -174G>C SNP in promotor of IL-6 gene could not be considered a risk factor for CLL. Larger prospective studies should be performed to confirm our results.

Gene polymorphism among hypertensive patients with coronary artery disease

The obstruction of the coronary arteries causes Coronary Artery Disease (CAD). It has been reported that interleukin-6 gene is related to the development of cardiovascular diseases such as atherosclerosis and coronary artery disease. This was due to the large variability and short half-life of interleukin 6 (IL-6). There are few studies on the link between interleukin 6 and CAD on the patients with hypertension. Therefore, goal of this study was to see if there is a link between IL-6 gene polymorphisms and coronary artery disease with hypertension patients. The polymorphisms were carried out by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The data was determined for statistical significance using chi-square analysis. A significant difference was found in the GG genotype of IL-6 -174, which was more frequent in cases of CAD (48.67 %) than in controls (8%) and 95% CI was 0.473455 - 0.500326; P<0.010620511. The GG genotype of IL-6-572C/G polymorphism was more frequent in cases of CAD (42.6%) compared with controls (8%) and 95% CI 0.386724 - 0.480945; P<0.017939631). likewise, significant association of variant allele G with CAD patients was reported. Hypertension was significantly higher among patients as compared to controls (P<0.022847535). Our findings indicated that both gene polymorphisms may be associated with development of CAD.

The effects of different antihypertensive drugs on pain and joint space width of knee osteoarthritis - A comparative study with data from Osteoarthritis Initiative

Hypertension was one common comorbidity of knee osteoarthritis (KOA), but the effect of different types of antihypertensive drugs on pain and joint space width (JSW) was unclear and not compared. Four hundred ninety KOA patients using one of the beta-blockers, ACE inhibitors, angiotensin receptor blockers, Calcium channel blockers (CCBs), or thiazide diuretics were followed for four years. The blood pressure, cumulative knee replacement rate, Womac pain, and JSW were compared among groups. All data were from the Osteoarthritis Initiative project. The CCBs group has the highest systolic blood pressure, replacement rate, and pain score at most visit timepoints. At baseline, the CCBs group was with significantly higher pain score than the beta-blockers group (3.3 vs 1.3, p < .05), the angiotensin receptor blockers group (3.3 vs 1.4, p < .05), and the thiazide diuretics group (3.3 vs 1.6, p < .05) in male; the CCBs group was with significantly higher pain score than the beta-blockers group (3.8 vs 2.0, p < .01), and the angiotensin receptor blockers group (3.8 vs 2.2, p < .05) in female. The results of females at 36 months were similar to the baseline. Among the common antihypertensive drugs, CCBs were associated with high replacement rates, high pain scores, and less JSW in KOA patients.

Dietary Acid Load and Its Interaction with IGF1 (rs35767 and rs7136446) and IL6 (rs1800796) Polymorphisms on Metabolic Traits among Postmenopausal Women

The objective of this study was to explore the effects of dietary acid load (DAL) and IGF1 and IL6 gene polymorphisms and their potential diet–gene interactions on metabolic traits. A total of 211 community-dwelling postmenopausal women were recruited. DAL was estimated using potential renal acid load (PRAL). Blood was drawn for biochemical parameters and DNA was extracted and Agena^® MassARRAY was used for genotyping analysis to identify the signalling of IGF1 (rs35767 and rs7136446) and IL6 (rs1800796) polymorphisms. Interactions between diet and genetic polymorphisms were assessed using regression analysis. The result showed that DAL was positively associated with fasting blood glucose (FBG) (β = 0.147, p < 0.05) and there was significant interaction effect between DAL and IL6 with systolic blood pressure (SBP) (β = 0.19, p = 0.041). In conclusion, these findings did not support the interaction effects between DAL and IGF1 and IL6 single nucleotide polymorphisms (rs35767, rs7136446, and rs1800796) on metabolic traits, except for SBP. Besides, higher DAL was associated with higher FBG, allowing us to postulate that high DAL is a potential risk factor for diabetes.

Genetic Variation of a −176g>c Interleukin-6 Correlated with White Blood Cells Count in Obesity of Indonesia

BACKGROUND: Obesity is a risk factor for cardiovascular disease. Obesity can trigger inflammation by increasing the synthesis of interleukin-6 (IL-6) which leads to leukocyte recruitment, differentiation of B lymphocytes, activating T lymphocyte cells, and triggering hematopoiesis. Variations in the IL-6 promoter gene are known to affect transcription rates. The previous studies have still found different results regarding the relationship between these gene variations and blood cell numbers. AIM: This study aimed to determine the influence of IL-6 gene variation with white blood cells counts in obese people of Indonesia. METHODS: A total of 148 people participated in this cross-sectional study. The number of obese people was 80 subjects and there were 68 non-obese people as controls. Obesity was determined based on the criteria of Asians. RESULTS: Genotype CC was not found in this study, while the GC genotype was found only in the obese group. The GG genotype in obese group had waist circumference, diastolic blood pressure, and higher lymphocyte rates significantly higher than the non-obese group (p < 0.05). CONCLUSIONS: Variation of −174G>C IL-6 gene is associated with high white blood cell counts, especially lymphocytes number in obese people in Indonesia.

The effect of polymorphisms (174G> C and 572C> G) on the Interleukin-6 gene in coronary artery disease: a systematic review and meta-analysis

Background

Coronary Artery Disease (CAD) is caused by the blockage of the coronary arteries. it is argued that there has an association between the Interleukin-6 gene and the occurrence of atherosclerosis, coronary artery disease, Due to the short half-life and high variability of Interleukin-6 (IL-6), limited studies have been performed on the association of serum levels of interleukin-6 with coronary artery disease. The aim of this study is to investigate the relationship between IL-6 gene polymorphisms and coronary artery disease.

Methods

This study was conducted as a meta-analysis of selected articles with no lower time limit and upto March 2020. Articles related to the subject were obtained by searching several data sources,such as the SID, IranDoc, Scopus, Embase, Web of Science (ISI), PubMed, Science Direct, and Google Scholar databases. The heterogeneity of the studies was assessed using the I² index in the Comprehensive Meta-Analysis software.

Results

The GG genotype of the IL-6174 G> C polymorphism with a 0.8 odds ratio tended to reduce the risk of CAD by 20%. The odds ratio of CAD in CG and GG genotypes were found to be 1.16 and 1.48 times respectively, indicating the increasing effect of these two genotypes. In the IL-6-572 C>G polymorphism, CG and GG genotypes increased the risk of CAD by 1.21 and 1.27 times respectively, and the CC genotype tended to reduce the risk of CAD by 15%, considering the odds ratio of 0.85.

Conclusion

This study showed a relationship between IL-6174G> C and Interleukin-6 (IL-6) 572 C>G genes and coronary artery disease. Moreover, the protective effects of GG genotype in IL-6 gene 174 G> C and CC genotype in IL-6 gene 572 C>G gene were reported. The study also confirmed that the CG and CC genotypes of the G>C IL-6174 gene have an increasing effect on coronary artery disease. Moreover, CG and GG genotypes in the IL-6 gene 572 C>G increased the risk of developing CAD. It should be noted that the increased risk of developing CAD was limited to meta-analytic studies in reported literatures.

Interaction between and impact of IL-6 genotype and alpha-tocopherol levels on periodontal condition in aging individuals

BACKGROUND AND OBJECTIVES

Few studies have assessed the possible interaction between and impact of IL-6 variants and serum α-tocopherol levels on periodontal condition in older individuals. Here, we assessed the relationship between IL-6 variants and serum α-tocopherol levels on periodontal condition by considering effect modification.

MATERIAL AND METHODS

Among the study participants, 359 who were 71 years of age underwent a dental examination, biochemical analysis, and interview. After dividing the participants into tertiles based on serum α-tocopherol levels, we conducted Poisson regression analysis to compare the prevalence rate ratio (PRR) for periodontal disease markers with the IL-6 genotype (rs1800796) based on each tertile adjusted by the number of teeth present (offset).

RESULTS

The PRRs of the IL-6 genotype for periodontal condition (probing pocket depth [PPD], clinical attachment level [CAL], and bleeding on probing [BOP]) which were adjusted by the number of teeth present (offset) were 1.17 (P < .001), 1.37 (P < .001), and 1.08 (P = .048), respectively. In addition, a significant association was found between the reciprocal number of PRRs of the IL-6 genotype and three serum α-tocopherol levels. The adjusted PRRs (± standard error) of the IL-6 genotypes for PPD were 0.48 (0.12) for the first group (P < .001), 1.54 (0.04) for the second group (P < .001), and 2.11 (0.03) for the third group (P < .001); similar tendencies were seen for CAL and BOP.

CONCLUSION

The results of this study suggest a potential association between the IL-6 genotype and periodontal condition in relation to serum antioxidant concentrations.

Impaired Multisensory Integration Predisposes the Elderly People to Fall: A Systematic Review

Background: This systematic review pooled all the latest data and reviewed all the relevant studies to look into the effect of multisensory integration on the balance function in the elderly.

Methods: PubMed, Web of Science and Scopus were searched to find eligible studies published prior to May 2019. The studies were limited to those published in Chinese and English language. The quality of the included studies was assessed against the Newcastle-Ottawa Scale or an 11-item checklist, as recommended by Agency for Healthcare Research and Quality (AHRQ). Any disagreement among reviewers was resolved by comparing notes and reaching a consensus.

Results: Eight hundred thirty-nine records were identified and 17 of them were included for systematic review. The result supported our assumption that multisensory integration works on balance function in the elderly. All the 17 studies were believed to be of high or moderate quality.

Conclusions: The systematic review found that the impairment of multisensory integration could predispose elderly people to fall. Accurate assessment of multisensory integration can help the elderly identify the impaired balance function and minimize the risk of fall. And our results provide a new basis for further understanding of balance maintenance mechanism. Further research is warranted to explore the change in brain areas related to multisensory integration in the elderly.

Association of IL-6 −174 G>C Polymorphism with Susceptibility to Colorectal Cancer and Gastric Cancer: a Systematic Review and Meta-Analysis

Background: The −174G>C (rs1800795) polymorphism at interleukin 6 (IL-6) gene has been reported to be related with the occurrence of colorectal (CRC) and gastric (GC) cancers. However, the results had been conflicting and controversial. In order to give a comprehensive and precise result, we summarized available data to analyze the association of this polymorphism with CRC and GC risk. Methods: A comprehensive literature search on PubMed, Elsevier Science Direct, and CNKI database was performed to identify all eligible studies up to May 15, 2019. The strength of association was assessed by odds ratios (ORs) with 95% confidence intervals (CI). Results: A total of 29 case-control studies including 16 studies with 7,560 cases and 9,574 controls on CRC and 13 studies with 1,445 cases and 2,918 controls on GC were selected. Overall, pooled data showed that the IL-6 −174G>C polymorphism was not significantly associated with increased risk of CRC and GC in overall. When stratified by ethnicity, we found a statistically significant association between the IL-6 −174 G>C polymorphism and CRC risk in Asians (CC vs. GG: OR = 1.860, 95% CI 1.061–3.258, p = 0.030; and CC vs. CG+GG: OR = 1.941, 95% CI 1.131–3.331, p = 0.016). Conclusion: The meta-analysis suggests that IL-6 −174G>C polymorphism was not significantly associated with the increased risk of CRC and GC in overall population. However, the results showed that IL-6 −174G>C polymorphism may be associated with risk of GC in Asians. Further studies including a larger sample size will be necessary to clarify these results.

Genetic polymorphisms associated with reactive oxygen species and blood pressure regulation

Hypertension is the most prevalent cause of cardiovascular disease and kidney failure, but only about 50% of patients achieve adequate blood pressure control, in part, due to inter-individual genetic variations in the response to antihypertensive medication. Significant strides have been made toward the understanding of the role of reactive oxygen species (ROS) in the regulation of the cardiovascular system. However, the role of ROS in human hypertension is still unclear. Polymorphisms of some genes involved in the regulation of ROS production are associated with hypertension, suggesting their potential influence on blood pressure control and response to antihypertensive medication. This review provides an update on the genes associated with the regulation of ROS production in hypertension and discusses the controversies on the use of antioxidants in the treatment of hypertension, including the antioxidant effects of antihypertensive drugs.

Arterial Hypertension and Interleukins: Potential Therapeutic Target or Future Diagnostic Marker?

Hypertension as a multifactorial pathology is one of the most important cardiovascular risk factors, affecting up to 30-40% of the general population. Complex immune responses are involved in the inflammatory mechanism of hypertension, with evidence pointing to increased inflammatory mediators even in prehypertensive patients. Increased vascular permeability, thrombogenesis, and fibrosis, effects that are associated with sustained hypertension, could be attributed to chronic inflammation. Chronic inflammation triggers endothelial dysfunction via increased production of ROS through proinflammatory cytokines. Increased serum level of proinflammatory cytokines such as IL-1β, IL-6, IL-8, IL-17, IL-23, TGFβ, and TNFα in hypertensive patients has been associated with either increased blood pressure values and/or end-organ damage. Moreover, some cytokines (i.e., IL-6) seem to determine a hypertensive response to angiotensin II, regardless of blood pressure values. Understanding hypertension as an inflammatory-based pathology gives way to new therapeutic targets. As such, conventional cardiovascular drugs (statins, calcium channels blockers, and ACEIs/ARBs) have shown additional anti-inflammatory effects that could be linked to their blood pressure lowering properties. Moreover, anti-inflammatory drugs (mycophenolate mofetil) have been shown to decrease blood pressure in hypertensive patients or prevent its development in normotensive individuals. Further research is needed to evaluate whether drugs targeting hypertensive-linked proinflammatory cytokines, such as monoclonal antibodies, could become a new therapeutic option in treating arterial hypertension.

Factors correlated with the improvement of endothelial dysfunction during Abatacept therapy in patients with rheumatoid arthritis

Background

Rheumatoid arthritis patients are exposed to a high risk of cardiovascular morbidity and mortality even in the early phases of the disease.

Methods

We evaluated carotid common carotid intimal media thickness (ccIMT) intimal thickness and brachial flow-mediated dilation (FMD) of 45 rheumatoid arthritis patients without known cardiovascular risk factors or heart disease on a stable dose of prednisone 5.2±1.2 mg/day and Methotrexate 11.5±2.1 mg at baseline (T0) and after 12 months (T1) of treatment with Abatacept 125 mg/week. The comparison between T0 and T1 (t- and Mann-Whitney test), correlation (Spearman r), and predictivity (linear regression) of FMD, ccIMT vs clinical and laboratory parameters (disease activity 28 score, tumor necrosis factor alpha [TNFα], interleukin-6, erythrocyte sedimentation rate, C-reactive protein (CRP), CD3+, CD3+/CD4+, CD3+/CD8+, CD19+(B), CD20+(B), NK CD3-CD56+CD16+, CD14+ HLA DR+, CD4+CD28+, CD4+CD28, rheumatoid factor IgM, IgA, RF IgG, anti-citrullinated peptide antibodies) were also evaluated.

Results

During Abatacept treatment, ccIMT and FMD remained stable and disease activity 28 score, CRP, erythrocyte sedimentation rate, and interleukin-6 decreased significantly (p=0.0001, 0.002, 0.0002, 0.0001 respectively). At T0, only ccIMT resulted as correlated with baseline TNFα values (p=0.0245) in an inverse proportion. At T1, ccIMT correlated with CD3/CD8+ lymphocytes number (p=0.0351) and FMD with CRP (p=0.0075). In regression analysis, baseline ccIMT and FMD had a low predictivity for TNFα (p=0.011) and CRP (p=0.049) at T1, respectively.

Conclusion

This study shows that the endothelial function remained stable during Abatacept treatment.

Association of interleukin-6 polymorphisms with obesity or metabolic traits in young Mexican-Americans

Objective

The objective of the study is to investigate the association of interleukin-6 (IL6) promoter single-nucleotide polymorphisms rs1800797 (-597 G/A) and rs1800796 (-572 G/C) with obesity or metabolic syndrome in Mexican-Americans.

Methods

The rs1800797 and rs1800796 single-nucleotide polymorphisms were genotyped in Mexican-Americans (n = 437) from South Texas, and results were correlated with measures of obesity and metabolic syndrome including body mass index, waist circumference, blood pressure, cholesterol, triglycerides, glucose, liver enzymes, plasma IL6 and high-sensitive C-reactive protein (hs-CRP).

Results

Significant associations were found for the rs1800796 variant with increased waist circumference, insulin resistance, lower IL6 levels and higher hs-CRP levels. The rs1800797 variant showed no associations with metabolic traits but was associated with higher IL6 levels and lower hs-CRP levels.

Conclusions

Findings in this study support the anti-inflammatory, anti-obesity and glucose homeostatic roles of IL6 in Mexican-American youth.

Association between interleukin-6/6R gene polymorphisms and coronary artery disease in Russian population: influence of interleukin-6/6R gene polymorphisms on inflammatory markers

This study determined the genotype effects of interleukin (IL)-6/IL-6R single nucleotide polymorphisms (SNPs) on circulating levels of different cytokines in healthy and coronary artery disease (CAD) patients with different allele frequencies. In the control patients, rs1800795 showed significant differences in IL-18 concentrations between CC and CG and CC and GG genotypes (P=0.003 and 0.004, respectively). Furthermore, circulatory IL-1β was significantly different between GC and GG genotypes from the same SNP (P=0.038). In the diseased patients, significance was determined only for IL-2 (P=0.021) between the C and G homozygote allele carriers of rs1800795. The diseased GC and GG genotype carriers were statistically different for IL-2 (P=0.049) from the rs1800796 and for IL-4 (P=0.049) from the rs2228044. IL-4 was also statistically significant between the GC and CC genotypes from the rs2228043 of the IL-6R gene (P=0.025). The last combination of genotypes in the same gene for the same SNP was statistically significant for IL-10 (P=0.036). According to the logistic regression, only gender (odds ratio [OR] =2.43) and triglycerides (OR =1.98) could be taken as determinants of CAD, while examined SNPs genotypes were not identified as risk factors for CAD. In general, the IL-6 polymorphism genotypes were mainly associated with inflammatory cytokines, while the IL-6R polymorphism genotypes were associated with anti-inflammatory cytokines.

Cytokines Genotype-Phenotype Correlation in Nonalcoholic Steatohepatitis

NASH consists in lipid accumulation in hepatocytes that trigger oxidative stress, secretion of proinflammatory cytokines leading to steatohepatitis (NASH). The study aimed to investigate the levels of proinflammatory (TNF-α and IL-6) along with anti-inflammatory cytokine IL-10 in patients with NASH and to correlate the cytokines' level with their polymorphism. Sixty-six patients with NASH and 30 healthy volunteers were included in the study. The plasmatic level of IL-6, IL-10, and TNF-α were determined by ELISA. IL-10 -1082 G/A, IL-6 -174 G/C, and TNF-α -308 G/A polymorphisms were determined using the PCR-RFLP technique. IL-6, TNF-α, and CRP levels were significantly higher in patients with NASH. There was a positive correlation between proinflammatory cytokines and a negative correlation between IL-10 and proinflammatory markers. The G allele and GG genotype of IL-6 -174 G/C polymorphism were more frequently noticed in NASH patients. Regarding IL-10 -1082 G/A polymorphism, the AA genotype was correlated with NASH and with a low plasmatic level of IL-10. The A allele in position 308 of the TNF-α gene was associated with high level of cytokine. In conclusion, there was an imbalance between pro- and anti-inflammatory cytokines in NASH patients. IL-10 -1082 G/A and TNF-α -308 G/A genotypes were correlated with the plasmatic levels of cytokines.

Association between hypertension and risk of knee osteoarthritis: A meta-analysis of observational studies

Evidence from observational studies shows that hypertension may be a risk factor for knee osteoarthritis (OA). However, the relationship between hypertension and knee OA risk remains controversial. This study aimed to quantitatively assess the relationship between hypertension and risk of knee OA.Three electronic databases (PubMed, Embase, and Cochrane Library) were searched up to July 25, 2016. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were extracted from the included observational studies. Publication bias, heterogeneity test, and subgroup analyses were performed.Eight studies including 2 cohort studies and 6 cross-sectional studies with 9762 participants were finally included in this meta-analysis. The results showed that hypertension was significantly associated with higher radiographic knee OA and symptomatic knee OA risks of 2.01 (95% CI, 1.28-3.15, I = 90.2%, P for heterogeneity <.001) and 1.49 (95% CI, 1.26-1.77, I = 0%, P for heterogeneity <.412), respectively. No publication bias was detected. The subgroup analysis showed that the study design did not influence the results (radiographic knee OA: OR = 1.42, 95% CI, 1.19-1.71 for cross-sectional studies and OR = 2.17, 95% CI, 1.30-3.63 for cohort studies; and symptomatic knee OA: OR = 1.85, 95% CI, 1.10-3.13) for cross-sectional studies and OR = 2.74, 95% CI, 1.81-4.16 for cohort studies).This meta-analysis showed that there was a significant relationship between hypertension and knee OA (both radiographic and symptomatic). However, further original studies are needed that use a better design.

Effects of Aging in Multisensory Integration: A Systematic Review

Multisensory integration (MSI) is the integration by the brain of environmental information acquired through more than one sense. Accurate MSI has been shown to be a key component of successful aging and to be crucial for processes underlying activities of daily living (ADLs). Problems in MSI could prevent older adults (OA) to age in place and live independently. However, there is a need to know how to assess changes in MSI in individuals. This systematic review provides an overview of tests assessing the effect of age on MSI in the healthy elderly population (aged 60 years and older). A literature search was done in Scopus. Articles from the earliest records available to January 20, 2016, were eligible for inclusion if assessing effects of aging on MSI in the healthy elderly population compared to younger adults (YA). These articles were rated for risk of bias with the Newcastle-Ottawa quality assessment. Out of 307 identified research articles, 49 articles were included for final review, describing 69 tests. The review indicated that OA maximize the use of multiple sources of information in comparison to YA (20 studies). In tasks that require more cognitive function, or when participants need to adapt rapidly to a situation, or when a dual task is added to the experiment, OA have problems selecting and integrating information properly as compared to YA (19 studies). Additionally, irrelevant or wrong information (i.e., distractors) has a greater impact on OA than on YA (21 studies). OA failing to weigh sensory information properly, has not been described in previous reviews. Anatomical changes (i.e., reduction of brain volume and differences of brain areas' recruitment) and information processing changes (i.e., general cognitive slowing, inverse effectiveness, larger time window of integration, deficits in attentional control and increased noise at baseline) can only partly explain the differences between OA and YA regarding MSI. Since we have an interest in successful aging and early detection of MSI issues in the elderly population, the identified tests form a good starting point to develop a clinically useful toolkit to assess MSI in healthy OA.

Interleukin-6-174G/C Polymorphism Contributes to Periodontitis Susceptibility: An Updated Meta-Analysis of 21 Case-Control Studies

Introduction. Chronic Periodontitis (CP) is suggested to be related to gene variations. Present study aims to quantitatively estimate the association between interleukin-6- (IL-6-) 174G/C polymorphism and CP susceptibility. Materials and Methods. Pubmed, Embase, and Web of Science were searched up to May 2016. The meta-analyses were performed using STATA 12.0. Results. 21 studies were yielded. Significant associations were found under heterozygote comparison and dominant model in studies fulfilling HWE (GC versus GG: OR = 0.690, 95% CI = 0.560–0.849, P = 0.000; CC + GC versus GG: OR = 0.690, 95% CI = 0.568–0.838, P < 0.001); significant associations were found under heterozygote comparison and dominant model in Caucasian studies fulfilling HWE (GC versus GG: OR = 0.752, 95% CI = 0.577–0.980, P = 0.035; CC + GC versus GG: OR = 0.737, 95% CI = 0.576–0.944, P = 0.016); significant associations were found under allele comparison, heterozygote comparison, and dominant model in Brazilian population (C versus G: OR = 0.648, 95% CI = 0.497–0.845, P = 0.001; GC versus GG: OR = 0.621, 95% CI = 0.441–0.876, P = 0.007; CC + GC versus GG: OR = 0.649, 95% CI = 0.470–0.896, P = 0.009). Conclusion. IL-6 174 polymorphism is associated with CP susceptibility. In Brazilian and Caucasian population, IL-6 174 GG genotype plays as a risk factor to CP.

Interleukin-6 polymorphisms and risk of coronary artery diseases in a Chinese population: A case-control study

Objective:

We aimed to evaluate the relationship between IL-6-174G>C, -572G>C and -597G>A polymorphisms and development of coronary artery diseases in a Chinese population.

Methods:

A total of 275 patients with coronary artery disease and 296 healthy control subjects were collected between January 2013 and November 2014. The IL-6 genotyping for -174G>C, -592G>C and -597G>A polymorphic sites was determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) according to the manufacturer instructions.

Results:

Using unconditional regression analysis, we observed that the AC and CC genotypes of IL-6 -592A>C were associated with the increased risk of developing coronary artery disease when compared with the AA genotype, and the adjusted ORs (95%CI) were 1.63(1.12-2.38) and 2.70(1.57-4.67), respectively. Additionally, the C allele of IL-6 -592A>C (OR=1.65, 95%CI=1.29-2.11) was correlated with a higher risk of developing coronary artery disease in comparison to the A allele. However, no relationship was found between IL-6-174G>C and -597G>A polymorphisms and coronary artery disease susceptibility.

Conclusion:

This study suggests that IL-6 -592G>C polymorphism is correlated with the risk of coronary artery disease. More well-designed prospective studies based on large sample size, multiple SNPs or haplotypes are required to confirm the current findings.