Periodontal disease is associated with increased coronary heart disease risk:A meta-analysis based on 38 case-control studies

AIM: To investigate whether periodontal disease(PD) is associated with increasing coronary heart disease(CHD) risk by performing a meta-analysis.METHODS: Two authors independently searched Pub Med and China National Knowledge Infrastructure up to January 10 th, 2013 for relevant case-control studies that investigated the association between PD and CHD. After quality assessment using Newcastle-Ottawa Scale and data extraction by two independent authors, the overall and subgroup meta-analyses were performed and publication bias were examined using the Comprehensive Meta-Analysis V2 software. Potential publication bias was assessed using visual inspection of the funnel plots, Egger linear regression test, and trims and fill method.RESULTS: Finally 38 relevant case-control studies were identified, involving 4950 CHD patients and 5490 controls. Eleven studies were rated low quality and 27 were high quality. Based on random-effects, a significant association was identified between PD and CHD(OR 3.79, 95%CI: 2.23-6.43, P < 0.001, I2 = 98.59%), and sensitivity analysis showed that this result was robust. Subgroup analyses according to adjusted/unadjusted ORs, source of control, methodological quality, end point, assessment of PD/CHD, and ethnicity also indicated a significant association. Publication bias was detected, and the estimated OR including the "missing" studies did not substantially differ from our estimate with adjustment for missing studies(OR 4.15, 95%CI: 2.62-6.54, P < 0.001).CONCLUSION: Based on the meta-analysis, PD is probably associated with CHD risk independently and significantly.

Multicenter case-control study of the risk factors for ulcerative colitis in China

AIM:To evaluate potential risk factors in the development of ulcerative colitis(UC) in China.METHODS:A total of 1308 patients with UC and 1308 age-matched and sex-matched controls were prospectively studied in China.The UC cases were collected from 17 hospitals in China from April 2007 to April 2010.Uniform questionnaires were designed to investigate risk factors including smoking,appendectomy,stress,socio-economic conditions,nonsteroidal antiinflammatory drugs(NSAIDs),oral contraceptives,diet,breastfeeding,infections and family sanitary conditions.Group comparisons by each factor were done using simple logistic regression analysis.Conditional logistic regression was used for multivariate analysis.RESULTS:By univariate analysis,the variables predictive of UC included feeling stress,light and heavy alcoholic drinking,spicy food,sugar consumption and infectious diarrhea,while heavy tea intake and tap water consumption were protective against UC.On multivariate analysis,the protective factor for UC was tap water consumption [odds ratios(OR) = 0.424,95%CI:0.302-0.594,P < 0.001];while the potential risk factors for UC were heavy sugar consumption(OR = 1.632,95%CI:1.156-2.305,P < 0.001),spicy food(light intake:OR = 3.329,95%CI:2.282-4.857,P < 0.001;heavy intake:OR = 3.979,95%CI:2.700-5.863,P < 0.001),and often feeling stress(OR = 1.981,95%CI:1.447-2.711,P < 0.001).Other factors,such as smoking habit,appendectomy,breastfeeding,a history of measles,rural or urban residence,education,oral contraceptives,and NSAID use have not been found to have a significant association with the development of UC in the present study.CONCLUSION:Our study showed tap water consumption was a protective factor for UC,while spicy food,heavy sugar consumption and often feeling stress were risk factors for UC in this Chinese population.

Risk factors of intrahepatic cholangiocarcinoma in patients with hepatolithiasis:a case-control study

BACKGROUND:Why 3.3% to 10% of all patients with hepatolithiasis develop intrahepatic cholangiocarcinoma (ICC) remains unknown.We carried out a hospital-based case-control study to identify risk factors for the development of ICC in patients with hepatolithiasis in China.METHODS:Eighty-seven patients with pathologically diagnosed hepatolithiasis associated with ICC and 228 with hepatolithiasis alone matched by sex,age (±2 years),hospital admittance and place of residence were interviewed during the period of 2000-2008.Odds ratios (OR) and 95% confidence intervals (CI) were calculated for each risk factor.RESULTS:Among the patients with hepatolithiasis associated with ICC,the mean age was 57.7 years and 61.0% were female Univariate analysis showed that the significant risk factors for ICC development in hepatolithiasis were smoking,family history of cancer,appendectomy during childhood (under age 20),and duration of symptoms >10 years.In multivariate stepwise logistic regression analysis,smoking (OR=1.931,95% CI:1.000-3.731),family history of cancer (OR=5.175,95% CI:1.216-22.022),and duration of symptoms >10 years (OR=2.348 95% CI:1.394-3.952) were independent factors.CONCLUSION:Smoking,family history of cancer and duration of symptoms >10 years may be risk factors for ICC in patients with hepatolithiasis.

Risk Factors of Low Back Pain among the Chinese Occupational Population:A Case-control Study

Objective To explore the risk factors of low back pain among the Chinese occupational population in several major industries. Methods A total of 7200 subjects （3600 cases and 3600 controls） were randomly sampled from a cross-sectional study, and they were investigated for individual and occupational factors of low back pain. The potential risk factors were first selected by using chi-square tests. Secondly, collinearity diagnosis proceeded by using the Kendall＇s rank correlation. Finally, binary logistic regression model was used for multi-factor analysis. Results Collinearity diagnosis showed that there was a severe collinearity problem among the potential risk factors of low back pain. Logistic regression model included 20 variables with statistical significance. Bending neck forward or holding neck in a forward posturefor long periods （0R=1.408） was the most important risk factor inducing low back pain in this study, followed by bending heavily with the trunk （0R=1.402）, carrying out identical work almost for the whole day （0R=1.340）. Additionally, suHicient normal break was a protective factor of low back pain. Conclusion Low back pain among the Chinese occupational population was associated with body height, occupation, work organization, physical work, working posture, and others. All these risk factors could be regarded as the indicators of low back pain, and some relevant preventive measures should be taken to reduce low back pain risk.

Environmental and Psycho-social Factors Related to Prostate Cancer Risk in the Chinese Population:a Case-control Study

Objective To study the risk environmental and psycho-social factors associated to prostate cancer （PCa） in Chinese population. Methods 250 PCa patients and 500 controls were enrolled in this case-control study. Information was collected and logistic regression analysis was used to estimate the odds ratios （OR） and 95% confidence intervals （95% CI） for relationship between lifestyle, eating habits and psycho-social factors with PCa risk. Results Green vegetables and green tea were associated with a decreased risk of PCa （0R=0.39, 95% CI： 0.28-0.53; 0R=0.59, 95% Cl： 0.40-0.87, respectively）. Family history of PCa （0R=7.16, 95% CI： 2.01-25.49）, history of prostate diseases （0R=2.28, 95% Cl： 1.53-3.41）, alcohol consumption （0R=1.97, 95% CI： 1.33-2.90）, red meat consumption （0R=1.74, 95% CI： 1.20-2.52）, barbecued （0R=2.29, 95% CI： 1.11-4.73） or fried （0R=2.35, 95% CI： 1.24-4.43） foods were related with increased PCa risk. Negative psycho-social factors including occupational setbacks （0R=1.61, 95% CI： 2.00-2.59）, marital separation （0R=1.94, 95% CI： 1.29-2.91）, self-contained suffering {0R=2.37, 95% CI： 1.58-3.55）, and high sensitivity to the personal comments （0R=1.73, 95% CI： 1.18-2.54） were related to PCa. Conclusion Regular consumption of green vegetables and green tea may suggest protective effects on PCa. Alcohol consumption, red meat consumption and barbecued or fried foods were associated with PCa. Negative psycho-social factors may also play a role in the incidence of PCa in Chinese population.

Risk factors for the occurrence of insulinoma: a case-control study

BACKGROUND: The etiology of insulinoma is poorly understood. Few studies investigated the possible roles of environmental factors and lifestyle in the pathogenesis of insulinoma. The aim of this study is to identify risk factors associated with occurrence of insulinoma in the Chinese population. METHODS: This study consisted of 196 patients with insulinoma and 233 controls. Demographic information of the patients and controls and risk factors of the disease were analyzed. Univariate and unconditional multivariable logistic regression analyses were made to estimate odds ratios (ORs) and possible risk factors. RESULTS: Approximately 68.88% (135/196) of the patients were from rural areas in contrast to 10.30% (24/233) of the controls (P【0.0001). This difference was confirmed by the multivariate analysis (OR=4.950; 95% CI: 2.928-8.370). Family history of pancreatic endocrine tumor (OR=16.754; 95% CI: 2.125-132.057) and other cancers (OR=2.360; 95% CI: 1.052-5.291) was also related to a high-risk population of insulinoma. CONCLUSION: Rural residents or people who have a family history of pancreatic endocrine tumor and other cancers are a high-risk population of insulinoma.

Incidence, risk factors, and cumulative risk of delirium among ICU patients: A case-control study

Objectives: Delirium is a common acute cognitive impairment syndrome among intensive care unit (ICU) patients.This study was aimed to investigate the incidence,risk factors,and cumulative risk of delirium among ICU patients.Methods: A case-control study including clinical records of 452 patients were retrospectively analyzed.Delirium was assessed using the Confusion Assessment Method for the ICU and Richmond Agitation -Sedation Scale.Results: We found that 163 out of the 452 patients (36.1%) had delirium.Multivariate analysis showed that use of sedatives,length of ICU hospitalization,and physical restraint were independent risk factors for delirium.The additive effect of all three factors resulted to an odds ratio of 30.950.Conclusion: The incidence of delirium remained high.Thus,nurses shall strengthen the monitoring of delirium,regularly access the patient's level of calmness,and limit the use of physical restraint.

A Case-control Study of Environmental Risk Factors for Nonsyndromic Cleft of the Lip and/or Palate in Xuzhou,China

In this study, we sought to determine the association between environmental factors and nonsyndromic cleft of the lip and/or palate （NSCLP） to understand the etiology of the disease. A total of 200 NSCLP cases and 327 controls were recruited at the Maternal and Child Health Hospital of Xuzhou City. We conducted face-to-face interviews with the mothers of both cases and controls. The factors increasing the risk of NSCLP were a positive family history [odds ratio （OR）=56.74], pesticide exposure （OR=8.90）, and indoor decoration pollution （OR= 4.32）. On the other hand, the factors decreasing the risk of NSCLP were a high education level （OR=0.22） and supplementation of folic acid （OR=0.23） and multivitamins （OR=0.16）. Positive family history, pesticide exposure, and indoor decoration pollution are associated with the risk of NSCLP. In contrast, high education level and folic acid and multivitamin supplementation are protective factors against NSCLP.

Lyme Borreliosis-associated Risk Factors in Residents of Beijing Suburbs: a Preliminary Case-control Study

A population-based case-control study was conducted to evaluate the relative fac^tors in the environments, agricultural works, outdoor activities, and the effectiveness of Lyme borreliosis （LB）- associated personal protective measure.c; in Beijing. Thirty-four cases and 272 controls were personally interviewed by well-trained interviewers. Venous blood samples were taken from eac：h subject. Sowing or harvesting in summer （OR=2.571, 95% CI： 1.109-5.962）, living in house with weeding in the yard （OR=2.247, 95% CI： 1.062-4.755）.

Associations between coagulation factorⅫ,coagulation factorⅪ,and stability of venous thromboembolism:A case-control study

BACKGROUND Pulmonary embolism(PE)is a fatal clinical syndrome that is generally caused by an embolus from unstable deep venous thrombosis(DVT).However,clinical and biochemical factors that are related to the stability of DVT are not fully understood.AIM To evaluate the relationships between plasma antigen levels of factor XII(FXII:Ag)and factor XI(FXI:Ag)with the stability of DVT.METHODS Patients with DVT and no PE,DVT and PE,and controls with no DVT or PE that matched for age,gender,and comorbidities were included in this study.FXII:Ag and FXI:Ag in peripheral venous blood were measured using enzyme-linked immunosorbent assays.RESULTS Using the 95th percentile of FXI:Ag in patients with DVT and PE as the cut-off,a higher FXI:Ag was associated with a higher risk of unstable DVT(odds ratio:3.15,95%confidence interval:1.18-8.43,P=0.019).Stratified analyses showed consistent results in patients≤60 years(P=0.020),but not in those>60 years(P=0.346).CONCLUSION Higher plasma FXI:Ag might be a marker for unstable DVT,which might be associated with PE in these patients.

Association between Prenatal Environmental Factors and Child Autism: A Case Control Study in Tianjin,China

Objective To investigate the association between autism and prenatal environmental risk factors.Methods A case-control study was conducted among 193 children with autism from the specialeducational schools and 733 typical development controls matched by age and gender by usingquestionnaire in Tianjin from 2007 to 2012. Statistical analysis included quick unbiased efficientstatistical tree （QUEST） and logistic regression in SPSS 20.0.Results There were four predictors by QUEST and the logistic regression analysis, maternal airconditioner use during pregnancy （OR=0.316, 95% CI： 0.215-0.463） was the single first-level node（χ2=50.994, P=0.000）; newborn complications （OR=4.277, 95% CI： 2.314-7.908） and paternalconsumption of freshwater fish （OR=0.383, 95% CI： 0.256-0.573） were second-layer predictors（χ2=45.248, P=0.000; χ2=24.212, P=0.000）; and maternal depression （OR=4.822, 95% CI： 3.047-7.631）was the single third-level predictor （χ2=23.835, P=0.000）. The prediction accuracy of the tree was 89.2%.Conclusion The air conditioner use during pregnancy and paternal freshwater fish diet might bebeneficial for the prevention of autism, while newborn complications and maternal depression might bethe risk factors.

Risk factors for Parkinson's disease and interaction analysis in Chinese patients

BACKGROUND： The etiology of Parkinson＇s disease （PD） remains unclear. The majority of studies have focused on the correlation between various factors and PD, with very different conclusions. To date, there has been no study on the interaction between PD family history and other risk factors, and very few studies have reported on hedtability. OBJECTIVE： To explore the risk factors for PD, the interaction between family history and other risk factors, and the impact of genetic factors on PD. DESIGN, TIME AND SETTNG： A paired, retrospective, case-control study was performed at the Department of Neurology, Qilu Hospital of Shandong University from November 2006 to October 2008. PARTICIPANTS： The case group included 157 Chinese PD patients selected from the Department of Neurology, Qilu Hospital of Shandong University in China from 2006 to 2008. An additional 157 patients treated in the same department during the same period were selected as the control group, and they were paired with regard to gender, age, and nationality to the case group. METHODS： Various scored factors were investigated in all participants. The association between various factors and PD was analyzed using univariate and multivariate logistic regression analysis. Interaction analysis between family history and other risk factors was performed using a logistic regression model. Heritability analysis was performed with the Falconer method. MAIN OUTCOME MEASURES： Risk factors for PD, interaction between family history and other risk factors, and heritability. RESULTS： Logistic regression analysis showed that family history, mental work, insecticide exposure, alcohol, and depression positively correlated with PD （odds ratio = 6.75, 2.37, 2.42, 2.03, 5.20, P〈 0.05）, whereas smoking had a negative correlation with PD （odds ratio = 0.49, P 〈 0.001）. The proportions of the effect attributable to interaction of family history and insecticide exposure, alcohol, and depression were 55.2%, 34.0%, and 41.4%, respectively, with a relative excess risk due to interaction of 8.96, 3.31, and 7.85, respectively. PD heritability from first-degree relatives was （36.86 ± 5.76） % and from second-degree relatives was （20.66 ± 6.81） %. CONCLUSION： Family history, mental work, insecticide exposure, alcohol, and depression were determined to be risk factors for PD, whereas smoking was a protective factor. Family history had a positive interaction with coexisting risk factors. Genetic factors had a smaller action on PD than environmental factors.

A case－control study on risk factors of stress fractures in military recruits during basic training

Stress fracture(SF) is an important training injury with a high incidence during recruits' basic training. In order to primarily investigate its risk factors and to provide etiologic threads for a further study,we carried out a case control study on SF. The results of univariate analysis and multivariate logistic regression analysis revealed that attending training on the occasion of injury or fatigue , and a lower length ratio of tibia and pelvic limb were the main risk factors of SF. The authors are of the opinion that compared with the absolute length of tibia , the relative length of tibia(tibia length/pelvic limb length) may be more relevant to the tibia biomechanical characteristics. , The harm of attending training under the circumstances of injury or fatigue is discussed in this paper.

Evidence and thinking on risk factors of hypertensive intracerebral hemorrhage: a meta-analysis

Background:To explore the related risk factors of hypertensive intracerebral hemorrhage(ICH)through meta-analysis,and to provide evidence-based medical basis for preventing ICH in hypertensive patients.Methods:The databases of CNKI,Wanfang,VIP,CBM,PubMed,Web of Science and Cochrane Library were searched by computer.Case control study on risk factors for hypertensive intracerebral hemorrhage were collected from the database establishment to October 2021.Two reviewers independently screened the literature,extracted the data,and evaluated the bias risk of the included studies.Meta-analysis was conducted on the results of the included studies using RevMan5.3 software.Results:A total of 7 studies were included,including 1512 patients.Meta-analysis results showed that:Smoking history(OR=6.23,95%CI(4.32,8.99),P<0.00001),drinking history(OR=7.24,95%CI(1.96,26.72),P=0.003),diabetes mellitus(OR=47.52,95%CI(10.31,219.31),P<0.00001),coronary heart disease(OR=9.90,95%CI(2.96,33.13),P=0.0002),daily salt intake(OR=10.21,95%CI(2.69,38.79),P=0.0006),failure to take medication regularly on time(OR=10.62,95%CI(5.40,20.91),P<0.00001),total cholesterol(OR=6.58,95%CI(2.45,17.65),P=0.0002),triglyceride(OR=8.63,95%CI(6.70,11.12),P<0.00001),body mass index(OR=6.63,95%CI(4.56,9.64),P<0.00001)and experiencing severe economic difficulties(OR=23.97,95%CI(14.82,38.77),P<0.00001)were risk factors for hypertensive intracerebral hemorrhage.Conclusion:Controlling smoking,drinking,reducing daily salt intake,controlling body weight,preventing diabetes and coronary heart disease,low-fat diet,controlling total cholesterol and triglyceride,taking antihypertensive drugs regularly and improving economic status can prevent hypertensive cerebral hemorrhage.

2018—2022年某三级口腔专科医院工作人员职业暴露情况调查

目的:探讨口腔专科工作人员职业暴露危险因素和职业伤害情况,为制定针对性职业防护措施提供依据。方法:回顾性分析2018年1月1日—2022年12月31日某三级口腔专科医院工作人员的职业暴露现状,探讨口腔专科医护工作人员职业暴露的风险因素。结果:5年职业暴露率分别为9.65%、6.54%、4.96%、5.38%、3.96%。151名职业暴露人员中,84.77%的职业暴露源不明;以女性[128人(84.77%)]、护士[63人(41.72%)]为主;暴露科室主要以综合门诊科/部(21.85%)和牙周黏膜科(17.22%)为主;主要发生于口腔诊疗操作(48.34%);08:00~11:59(51.66%)是1 d中发生职业暴露次数最多的时间;手部(87.42%)是最主要的暴露部位;暴露器械多为根管锉、牙科钻、洁治器头(38.41%)及注射针头(33.11%);2020年后工作人员职业防护考核得分有大幅度提升(P<0.05)。结论:口腔专科职业暴露风险较综合医院有其专科特色,建议在推广安全器具使用的基础上,进行喷溅操作多、诊疗次数多的操作之前开展病人血源性检测,同时在进行职业安全防护、标准操作规程、职业暴露处置等相关培训时要结合人群特点,培训形式应与受训者群体特征相适应。

麝香通心滴丸预处理对大鼠心肌缺血再灌注损伤的保护作用机制

目的:观察麝香通心滴丸预处理对大鼠心肌缺血再灌注(I/R)损伤后心肌细胞和血管的保护作用及潜在机制。方法:将60只雄性SD大鼠随机分为假手术组(Sham组)、I/R组、麝香通心滴丸组(SXTX组)和阳性组,每组15只。SXTX组以18.90 mg/(kg·d)的浓度灌胃;阳性组以尼可地尔1.35 mg/(kg·d)的浓度灌胃;Sham组和I/R组给予等体积去离子水灌胃。各组均灌胃1周后,行冠状动脉前降支结扎-松解手术,除Sham组外其余各组大鼠结扎左冠状动脉前降支30 min后,再灌注120 min,构建心肌I/R模型。通过心肌苏木精-伊红(HE)染色、心肌Masson染色观察大鼠心肌组织及血管改变;电镜观察心肌细胞和血管的超微结构改变;免疫组织化学法观察血管相关蛋白低氧诱导因子-1α(HIF-1α)和血管内皮生长因子(VEGF)表达情况。结果:与Sham组比较,I/R组大鼠心肌细胞坏死和血管损伤明显,心肌组织中HIF-1α表达增加;与I/R组相比,SXTX组心肌细胞和血管病理结构损伤减轻,缺血区心肌组织VEGF含量明显增加。结论:麝香通心滴丸预处理可保护大鼠心肌细胞和血管I/R损伤,可能与上调VEGF蛋白表达、促进缺血区微血管新生有关。

Correlation of human epidermal growth factor receptor protein expression and colorectal cancer

AIM:To investigate the correlation between human epidermal growth factor receptor(HER-2) protein expression and colorectal cancer(CRC) using a casecontrol study and meta-analysis.METHODS:Tumor tissue specimens from 162 CRC patients were selected for the case group.Fifty cases were randomly selected,and normal CRC tissue at least 10 cm away from the tumor margins of these cases was used to generate the control group.The expression of the HER-2 protein in the 162 CRC tissue samples and the 50 adjacent normal mucosa tissue samples was detected via immunohistochemistry.The experimental data were analyzed using SPSS 18.0software,and R software version 3.1.0 was utilized for further verification.RESULTS:The expression of HER-2 protein in the 162 CRC tissue samples was significantly higher than in the normal tissue specimens.The data showed that the expression of HER-2 in CRC was related to the Dukes' stage,the depth of invasion and lymph node metastasis.The HER-2-positive patients had lower 3-and 5-year OS rates than the HER-2-negative patients,but there was no significant difference.However,there was a statistically significant difference in the 3- and5-year disease-free survival(DFS) rates of HER-2-positive and HER-2-negative patients.The results of the meta-analysis showed that the expression of HER-2in CRC patients was statistically significantly increased over that of healthy people.The 3-year DFS rate in HER-2-positive patients was markedly lower than that in HER-2-negative patients.CONCLUSION:Down-regulation of HER-2 expression might be a dependable strategy for CRC therapy.

How Work Organization Affects the Prevalence of WMSDs: A Case-control Study

Objective In this study, we aimed at exploring the association between work-related musculoskeletal disorders（WMSDs） and work organization based on a case-control study. Methods A total of 1938 workers who claimed to suffer from WMSDs were selected from Beijing, Henan, Hubei, and the Guangdong province. The control group consisted of 2009 workers employed in similar industries without severe disease or musculoskeletal discomforts. We used a modified version of the questionnaire developed by the NMQ and the DMQ to investigate individual and work-related factors. Results A total of 13 variables（P〈0.1） were selected by the chi-square test and finally, 7 variables entered into the equation, with 6 variables reaching statistical significance（P〈0.05）. The odds ratios（OR） of ＇work changing with season＇ and ＇sufficient rest time＇ did not reach 1（0.749 and 0.441, respectively）. In addition, ＇sufficient rest time＇ seemed to be the stronger protective factor according to its higher standardized coefficient. And ＇repetitive work every minute＇, ＇constantly repetitive work＇（every day）, ＇shortage of site personnel＇, and ＇often switching shifts with others＇ seemed to be the risk factors. Conclusion Work organization may have comprehensive effects on the occurrence of WMSDs. This pattern of associations suggests that further investigation into the mechanism of how work organization affects the prevalence of WMSDs is required.

Mitochondrial DNA as a Risk Factor for False Positives in Case-Control Association Studies

During the last decade, hundreds of studies have been pub- lished examining whether significant associations exist be- tween mitochondrial DNA （mtDNA） variants and/or haplogroups （clades） and particular diseases （generally com- mon/complex diseases） （Fig. 1）. However, several authors have gathered evidence indicating a high incidence of false positive findings in mtDNA case-control association studies. Raule et al. （2007） and Herrnstadt and Howell （2004） showed various problems affecting mtDNA case-control association studies. Salas et al.

Genetic polymorphisms in pri-let-7a-2 are associated with ischemic stroke risk in a Chinese Han population from Liaoning, China: a case-control study

Ischemic stroke is a complicated disease, and its pathogenesis has been attributed to the occurrence of genetic polymorphisms.Evidence has suggested that the microRNA let-7a is involved in the pathogenesis of ischemic stroke.Pri-miRNA is the primary transcript, which undergoes several processing steps to generate pre-miRNA and, later, mature miRNAs.In this case-control study, we analyzed the distribution of prilet-7a-2 variants in patients at a high risk for ischemic stroke and the interactions of pri-let-7a-2 variants and environmental factors.Blood samples and clinical information were collected from 1086 patients with ischemic stroke and 836 healthy controls between December 2013 and December 2015 at the First Affiliated Hospital of China Medical University.We found that the rs1143770 CC genotype and the C allele were associated with a decreased risk of ischemic stroke, whereas the rs629367 CC genotype was associated with an increased risk for ischemic stroke.Moreover, these two single-nucleotide polymorphisms were in linkage disequilibrium in this study sample.We analyzed gene-environment interactions and found that rs1143770 exerted a combined effect on the pathogenesis of ischemic stroke, together with alcohol use, smoking, and a history of hypertension.Therefore, the detection of pri-let-7a-2 polymorphisms may increase the awareness of ischemic stroke risk.This study was approved by the Institutional Ethics Committee of the First Affiliated Hospital of China Medical University, China(approval No.2012-38-1) on February 20, 2012, and was registered with the Chinese Clinical Trial Registry(registration number: ChiCTR-COC-17013559) on December 27, 2017.