Retinal nerve fiber layer defects and chronic kidney disease:the Kailuan Eye Study

AIM:To investigate whether retinal nerve fiber layer defects(RNFLDs)is a potential risk factor for chronic kidney disease(CKD)in Chinese adults.METHODS:The Kailuan Eye Study was a populationbased study that included 14440 participants.All participants underwent detailed assessments,RNFLDs were diagnosed using color fundus photographs.RESULTS:Overall,12507 participants[8533 males(68.23%)]had complete systemic examination data and at least one evaluable fundus photograph.RNFLDs were found in 621 participants[5.0%;95%confidence interval(CI):4.6%-5.34%],and 70 cases of multiple RNFLDs were found(11.27%).After adjusting multiple factors,RNFLDs was significantly associated with CKD severity,the ORs of CKD stage 3,stage 4 and stage 5 were 1.698,4.167,and 9.512,respectively.Multiple RNFLDs were also associated with CKD severity after adjusting multiple factors,the ORs of CKD stage 3 and stage 5 were 4.465 and 11.833 respectively.Furthermore,2294 participants had CKD(18.34%,95%CI:17.68%-18.99%).After adjusting for other factors,CKD presence was significantly correlated with the presence of RNFLDs.CONCLUSION:The strongest risk factors for RNFLDs are CKD and hypertension.Conversely,RNFLDs can be an ocular feature in patients with CKD.Fundoscopy can help detect systemic diseases,and assessment for RNFLDs should be considered in CKD patients.

糖尿病前期成年人综合健康生活方式与糖尿病、心血管疾病、癌症和死亡的关联--来自中、美、英三个国家的四个队列研究

在糖尿病前期人群中,采取健康的生活方式可以有效预防糖尿病的发生。然而,健康生活方式与心血管疾病(cardiovascular disease,CVD)、癌症和死亡的长期风险之间的关联尚未阐明。本文旨在探究糖尿病前期人群中综合健康生活方式与上述多种健康结局之间的关联。本研究纳入的121254名糖尿病前期参与者来自以下4个前瞻性队列,包括中国的东风-同济队列(Dongfeng-Tongji,DFTJ)和开滦研究,英国生物银行(UK Biobank,UKB)和美国的国家健康与营养调查(National Health and Nutrition Examination Survey,NHANES;仅用于死亡分析)。随访期间,共诊断了18333例新发糖尿病病例、10829例新发心血管疾病病例、6926例新发癌症病例和9877例全因死亡。本文基于5个因素(从不吸烟或戒烟超过10年、适量饮酒、充足的体力活动、健康膳食和理想的腰围)构建综合健康生活方式评分。各因素均被分为健康水平(赋1分)和不健康水平(赋0分),评分的加和为综合健康生活方式评分(0~5分)。首先,采用Cox比例风险回归模型计算每个队列中综合健康生活方式评分与健康结局之间的关联;然后,通过随机效应模型的荟萃分析合并各独立队列结果的多变量校正的风险比(hazard ratio,HR)和95%置信区间(confidence interval,CI)。与生活方式最不健康(评分为0~1分)的研究对象相比,生活方式最健康(评分为4~5分)的研究对象具有更低的糖尿病、心血管疾病、癌症和死亡风险,合并的HR(95%CI)分别为0.57(0.48~0.69)、0.67(0.62~0.73)、0.80(0.73~0.88)和0.54(0.42~0.70)。根据研究对象的基线人口学特征和代谢健康状况进行亚组分析的结果也与主要分析的结果一致。总而言之,本研究对来自三个国家的4个队列的合并分析表明,在糖尿病前期人群中,坚持更健康的生活方式与糖尿病及主要并发症的发生风险降低有关。本研究的发现为临床指南和公共卫生政策提供了可靠证据。

Analysis of risk and protective factors associated with retinal nerve fiber layer defect in a Chinese adult population

AIM:To investigate the risk and protective factors associated with the retinal nerve fiber layer defect(RNFLD)in a Chinese adult population.METHODS:This study was a cross-sectional populationbased investigation including employees and retirees of a coal mining company in Kailuan City,Hebei Province.All the study participants underwent a comprehensive systemic and ophthalmic examination.RNFLD was diagnosed on fundus photographs.Binary logistic regression was used to investigate the risk and protective factors associated with the RNFLD.RESULTS:The community-based study included 14440 participants.There were 10473 participants in our study,including 7120 males(68.0%)and 3353 females(32.0%).The age range was 45-108y,averaging 59.56±8.66y.Totally 568 participants had RNFLD and the prevalence rate was 5.42%.A higher prevalence of RNFLD was associated with older age[P<0.001,odds ratio(OR):1.032;95%confidence interval(CI):1.018-1.046],longer axial length(P=0.010,OR:1.190;95%CI:1.042-1.359),hypertension(P=0.007,OR:0.639;95%CI:0.460-0.887),and diabetes mellitus(P=0.019,OR:0.684;95%CI:0.499-0.939).The protective factors of RNFLD were visual acuity(P=0.038,OR:0.617;95%CI:0.391-0.975),and central anterior chamber depth(P=0.046,OR:0.595;95%CI:0.358-0.990).CONCLUSION:In our cross-sectional community-based study,with an age range of 45-108y,RNFLD is associated with older age,longer axial length,hypertension,and diabetes mellitus.The protective factors of RNFLD are visual acuity and central anterior chamber depth.These can help to predict and evaluate RNFLD related diseases and identify high-risk populations early.

视网膜中央动脉直径及动静脉直径比值和动脉硬化之间的关系

目的:探讨视网膜血管直径对不同年龄人群动脉硬化的影响。方法:以参加2014年(第四次)健康体检且参加了臂踝脉搏波传导速度(baPWV)检测和眼底彩色照相检测者作为观察对象。根据世界卫生组织的年龄划分标准将研究对象分为3组:18~44岁组、45~59岁组和≥60岁组。首先采用多元线性回归分别分析总人群及不同年龄组人群视网膜中央动脉直径(CRAE)和视网膜动静脉直径比值(AVR)与baPWV的关联;其次采用多因素Logistic回归模型分别分析总人群CRAE和不同年龄组人群AVR对动脉硬化(baPWV≥14.00m/s)的影响。结果:CRAE和AVR随着年龄的增加而减小。多元线性回归分析,在45~59岁组和≥60岁组人群中CRAE和AVR与baPWV均呈负线性相关,CRAE和AVR每增加1单位,baPWV分别减小0.01、0.02、1.99和5.58m/s。多因素Logistic回归分析,在45~59岁组和≥60岁组人群中,CRAE每增加1μm,发生动脉硬化的风险均减小,其OR值(95%CI)分别为0.99(0.98~0.99)和0.98(0.97~0.99)。结论:在45~59岁组和≥60岁组人群中,CRAE和AVR与动脉僵硬度呈负线性相关,它们的增加是发生动脉硬化的保护因素。

Medical expenditure for esophageal cancer in China:a 10-year multicenter retrospective survey(2002-2011)

Background: Esophageal cancer is associated with substantial disease burden in China, and data on the economic burden are fundamental for setting priorities in cancer interventions. The medical expenditure for the diagnosis and treatment of esophageal cancer in China has not been fully quantified. This study aimed to examine the medical expenditure of Chinese patients with esophageal cancer and the associated trends.Methods: From 2012 to 2014, a hospital-based multicenter retrospective survey was conducted in 37 hospitals in 13 provinces/municipalities across China as a part of the Cancer Screening Program of Urban China. For each esophageal cancer patient diagnosed between 2002 and 2011, clinical information and expense data were extracted by using structured questionnaires. All expense data were reported in Chinese Yuan(CNY; 1 CNY = 0.155 USD) based on the2011 value and inflated using the year-specific health care consumer price index for China.Results: A total of 14,967 esophageal cancer patients were included in the analysis. It was estimated that the overall average expenditure per patient was 38,666 CNY, and an average annual increase of 6.27% was observed from 2002(25,111 CNY) to 2011(46,124 CNY). The average expenditures were 34,460 CNY for stage Ⅰ,39,302 CNY for stage Ⅱ,40,353 CNY for stage Ⅲ, and 37,432 CNY for stage IV diseases(P < 0.01). The expenditure also differed by the therapy type, which was 38,492 CNY for surgery, 27,933 CNY for radiotherapy, and 27,805 CNY for chemotherapy(P < 0.05).Drugs contributed to 45.02% of the overall expenditure.Conclusions: These conservative estimates suggested that medical expenditures for esophageal cancer in China substantially increased in the last 10 years, treatment for early-stage esophageal cancer costs less than that for advanced cases, and spending on drugs continued to account for a considerable proportion of the overall expenditure.

The association between orthostatic blood pressure changes and subclinical target organ damage in subjects over 60 years old

Background Although recent studies have indicated that both orthostatic hypotension and orthostatic hypertension independently predict cardiovascular events,the underlying mechanisms are still controversial.The aim of the study was to investigate the relationships between orthostatic changes and organ damage in subjects over 60 years old.Methods This is a prospective observational cohort study.One thousand nine hundred and ninety-seven subjects over 60 years old were enrolled.Participants were grouped according to whether they had a drop>20 mmHg in systolic or>10 mmHg in diastolic BP(orthostatic hypotension),an increase in mean orthostatic systolic blood pressure>20 mm Hg(orthostatic hypertension),or normal changes within 3 min of orthostatism.Multiple regression modeling was used to investigate the relationship between orthostatic hypotension,orthostatic hypertension and subclinical organ damage with adjustment for confounders.Results Orthostatic hypotension and orthostatic hypertension were found in 461(23.1%)and 189(9.5%)participants,respectively.Measurement of carotid intima-media thickness(IMT),brachial-ankle pulse wave velocity(baPWV),clearance of creatinine,and microalbuminuria were associated with orthostatic hypotension;measurement of IMT and baPWV were associated with orthostatic hypertension in a cruse model.After adjustment,IMT[odds ratio(OR),95%confidence interval(CI)per one-SD increment:1.385,1.052-1.823;P=0.02],baPWV(OR=1.627,95%CI:1.041-2.544;P=0.033)and microalbuminuria(OR=1.401,95%CI:1.002-1.958;P=0.049)were still associated with orthostatic hypotension,while orthostatic hypertension was only associated with IMT(OR=1.730,95%CI:1.143-2.618;P=0.009).Conclusions Orthostatic hypotension seems to be independently correlated with increased carotid atherosclerosis,arterial stiffness and renal damage in subjects over 60 years old.Orthostatic hypertension correlates with carotid atherosclerosis only.

Changes in pulse pressure × heart rate, hs-CRP, and arterial stiffness progression in the Chinese general population: a cohort study involving 3978 employees of the Kailuan Company

Background Pulse wave velocity(PWV) is a marker of arterial stiffness, which represents sub-clinical atherosclerosis. Pulsatile stress and high-sensitivity C-reactive protein(hs-CRP) are associated with arteriosclerosis. However, there is no prospective data confirming whether changes in pulsatile stress and inflammatory markers affect the progression of arterial stiffness. The aim of this study was to investigate the relationships over time between the effects of changes in pulsatile stress and hs-CRP, and arterial stiffness progression during a 2-year follow-up. Methods We performed a longitudinal study involving 3978 participants. All participants underwent a physical examination in 2010–2011 and 2012–2013, during which we measured participants’ hs-CRP levels, brachial–ankle pulse wave velocity(ba PWV), and pulsatile stress. Results Baseline hs-CRP was correlated with ba PWV(r = 0.18, P = 0.000);however the correlation was weaker than that with systolic blood pressure(r = 0.65), pulsatile stress(r = 0.57), and rate-pressure product(r = 0.58). Multiple linear regression analysis demonstrated that changes in pulsatile stress, mean arterial pressure, and low-density lipoprotein-C(LDL-C) were positively correlated with changes in ba PWV, with correlation coefficients of 0.27, 0.25, and 0.07, respectively, but not with changes in hs-CRP. Moreover, each 100-a U increase in pulsatile stress, 1 mm Hg increase in mean blood pressure, and 1 mmol/L increase in LDL-C was associated with a 3 cm/s, 4.78 cm/s, and 17.37 cm/s increase in ba PWV, respectively. Conclusions Pulsatile stress increases are associated with arterial stiffness progression, but that changes in hs-CRP had no effect on arterial stiffness progression. Hs-CRP may simply be a marker of inflammation in arterial stiffness and has no association with arterial stiffness progression.

Influencing factors for peripheral and posterior lesions in mild non-proliferative diabetic retinopathy--the Kailuan Eye Study

AIM:To explore the influencing factors of diabetes type 2 patients with mild non-proliferative diabetic retinopathy(NPDR)in the Kailuan area of Tangshan,Hebei Province,China.METHODS:In this non-interventional,retrospective study,683 patients with type 2 diabetes were included in the Kailuan Diabetic Retinopathy Study involving participants with diabetes in the community-based longitudinal Kailuan Study.Based on the undilated ultrawide field(200°;UWF)images and partial dilated digital fundus images,the diabetic retinopathy(DR)of the surveyed population was graded.Interobserver agreement was estimated by using Cohen’s Kappa statistics.The main outcome indicators included gender,age,weight,height,body mass index,blood pressure,circumferences of neck,waist and hip,current smoking,levels of fasting plasma glucose(FPG),hypersensitive C-reactive protein,creatinine,and cholesterol,etc.According to different lesions’locations of patients with mild NPDR,logistic regression models were used to estimate the odds ratios(ORs)and their 95%Cls of each risk factor.RESULTS:The study group of 683 patients included 570 males and 113 females.The mean age of the patients was62.18±9.41 y.Compared with dilated fundus examinations,there was fair agreement with the level of DR identified on UWF images in 63.91%of eyes(k=0.369,95%CI,0.00-0.00).Detected by UWF images,there were 98 patients with mild NPDR having peripheral retinal lesions,35 patients with mild NPDR having posterior lesions,44 patients with mild NPDR whose lesions were detected both in and out the standard two fields area,and 336 patients with non obvious DR.Parameters that conferred a statistically significant increased risks for mild NPDR with having peripheral retinal lesions were neck circumstance(OR,1.124;95%CI,1.044-1.211),and with posterior lesions were FPG(OR,1.052;95%CI,1.007-1.099).CONCLUSION:UWF is an effectiveness means of DR screening.Moreover,it is necessary to evaluate peripheral diabetic retinal lesions which can help to estimate the severity of DR.The phenomenon that nonuniform and inhomogeneous distribution of DR lesions has been found.And the influencing factors in mild NPDR are differing by different lesions’locations.

Correlation of the history of stroke and the retinal artery occlusion: a nested case-control study

AIM:To analyze the systemic factors including stroke history related to the retinal artery occlusion(RAO).METHODS:Patients with an exact diagnosis of RAO in the medical database of the Kailuan Corporation were identified as the case group.Five patients without RAO were added for each case from the Kailuan Study and matched for sex and age(age±2)as the control group.The Kailuan Study is a general population-based cohort study in northern China,in which a total of 101510 individuals(81110 men)aged 18-98 y were recruited to participate in the study.And the participants were bi-annually reexamined.The database of both groups was from Kailuan study of 2010 cohort.All the information,including the demographic characteristics,lifestyle behaviors,medical comorbidities,medical history,family medical history,drug usage,anthropometric measurements,blood pressure measurement,blood sample laboratory assessment,urine tests,and other physical examinations were all collected.A retrospective nested case-control method was used for this study.Conditional multivariate logistic regression was used to analyze the risk factors with SPSS 13.0 software and SAS 9.3 software.RESULTS:A total of 45 patients were included as the case group,and the control group included 225 patients.In the case group,28 patients(62.2%)had a central retinal artery occlusion(CRAO),and 17 patients(37.8%)had a branch retinal artery occlusion(BRAO).A total of 18 patients(40.0%)had a stroke before the RAO(mean 4.04±3.88 y before the RAO),and 31 patients(81.6%)had infarctions or malacia identified by the cranial computed tomography(CT)scans.The basal ganglia and centrum semiovale were the most frequently involved regions.Plaques in the common carotid artery were present in 32 patients(88.9%).Conditional multivariate logistic regression analysis showed that the RAO was found to be associated with the history of stroke(P=0.0023,OR=28.794;95%CI:3.322-249.586).CONCLUSION:A history of stroke can significantly increase the incidence of RAO.Exists of plaque in the carotid artery is mean more than its severe stenosis for RAO.

Possible Association of ACE Gene I/D Polymorphism With Blood Pressure——Lowering Response to Hydrochlorothiazide

Objective To explore the association between polymorphism in the ACE I/D gene and blood pressure-lowering response to hydrochlorothiazide （HCTZ） in 829 patients. Methods HCTZ 12.5 mg was taken once a day for six weeks. The blood pressure reduction and ratio reaching target blood pressure were compared in different ACE genotype groups. Results The reduction in SBP of patients carrying DD was greater than that in other groups carrying II or ID （12.2 mmHg versus 5.4 mmHg, 12.2 mmHg versus 4.4 mmHg, respectively, P〈0.05）. The reduction in MAP of patients carrying DD was also greater than that in other groups carrying II or ID （6.9 mmHg versus 3.9 mmHg, 6.9 mmHg versus 3.6 mmHg, respectively, P〈0.05）. The ratio reaching target blood pressure in DD groups was significantly higher than that in II or ID groups （P〈0.05）. The pre-treatment SBP, DD genotype, aldosterone levels entered the multi-linear regression model significantly and might affect the reduction of SBP. The pre-treatment DBP, aldosterone levels, DD genotype entered the multi-linear regression model significantly and might affect the reduction of DBP. The pre-treatment MAP, DD genotype, aldosterone levels entered the multi-linear regression model significantly and might affect the reduction of MAP. Conclusion ACE genotyping is associated with blood pressure-lowering response to HCTZ. Specific genotypes might be associated with the response to specific antihypertensive treatment.

Retinal nerve fiber layer thickness and retinal vascular caliber alterations in coal miners in northern China:a community-based observational study

AIM:To evaluate retinal nerve fiber layer thickness and retinal vascular caliber alterations in coal mine workers.METHODS:The community-based observational crosssectional study included 4004 participants of a subpopulation of the Kailuan Study.All the study participants underwent structured interviews with a standardized questionnaire,fundus photography and spectral-domain optical coherence tomography(OCT)examinations performed by trained doctors.RESULTS:The retinal nerve fiber layer thickness was significantly higher(P=0.006)and the central macular thickness was lower in coal miners(n=659,51.0±7.8 y)as compared to the control(working above the ground;n=477,51.8±7.5 y;P=0.032).Additionally,the downhole workers showed a significantly thicker retinal artery(P=0.012)and vein diameters(P<0.001).In multivariable regression,a thicker retinal nerve fiber layer was associated with a higher cumulative silica dust exposure(P=0.005)after adjusting for younger age and larger spherical equivalent.In a reverse pattern,a higher cumulative silica dust exposure(P=0.004)was significantly associated with a thicker retinal nerve fiber layer after adjusting for age,high-density lipoproteins and uric acid.Wider retinal vein diameters were associated with higher cumulative silica dust exposure(P=0.036)after adjusting for younger age and larger spherical equivalent.CONCLUSION:The retinal vessels diameters and retinal nerve fiber layer thickness are significantly thicker in long term of coal mining.The results of our study indicate that underground working environment may lead to retinal vessel dilation and inflammation.Thus,ocular examination might be needed within coal miners in order to monitor the occupational eye health as well as the incidence and progression of eye diseases.

Early-onset and later-onset cancer:trends,risk factors,and prevention in Northern China

The characteristics of early-onset(onset age<50 years)and later-onset(onset age≥50 years)cancers differ significantly.Identifying novel risk factors for both types of cancer is crucial for increasing awareness of cancer prevention and for reducing its burden.This study aimed to analyze the trends in incidence and risk factors for early-onset and late-onset cancers.We conducted a prospective study by drawing data from the Kailuan Study.This study included 6,741 participants with cancer(624 with early-onset cancer and 6,117 with later-onset cancer)and 6,780 matched controls among the 186,249 participants who underwent Kailuan health examinations from 2006 to 2019.The primary outcomes were cancer incidence rates,and associated risk factors for early-and later-onset cancer.Weighted Cox regression was used to calculate hazard ratios and 95% confidence intervals of each exposure factor for early-and later-onset cancer by cancer type.Populationattributable risk proportions were used to estimate the number of cases that could be prevented by eliminating a risk factor from the population.Except for liver cancer,incidence rates for nearly all types of cancer increased during the study period.Smoking,alcohol consumption,lipid metabolism disorders,hypertension,diabetes mellitus,fatty liver,and inflammation were associated with a significantly increased risk of cancer at multiple sites,but risk factors for cancer incidence differed by site.Smoking,alcohol consumption,inflammation,and hypertension were the major contributors to preventable cancer.The incidence of several different types of cancer,including earlyonset cancer,is increasing in northeastern China.Differences in risk factors between early-onset and later-onset malignancies may contribute to the divergence in the observed changes in incidence trends between these two specific types of cancer.

ncidence, Development, and Prognosis of Diabetic Kidney Disease in China： Design and Methods

Background： Although that glomerulonephritis is the major cause of end-stage renal disease in developing countries such as China, the increasing prevalence of diabetes has contributed to the changing spectrum of predialysis chronic kidney disease. Recent studies have revealed an increased proportion of patients with diabetic kidney disease （DKD） in hemodialysis populations in large cities in China. However, studies regarding the clinical phenotype of DKD in China are extremely limited. The incidence, development, and prognosis of diabetic kidney disease （INDEED） study aims to investigate the incidence, progression, and prognosis of DKD, as well as the associated genetic, behavioral, and environmental factors and biomarkers in patients with DKD in China. Methods： INDEED study is a prospective cohort study based on all participants with diabetes in the Kailuan study, which is a general population-based cohort study in northern China. Altogether, over 10,000 participants with diabetes will be followed biennially. Questionnaires documenting general characteristics, behavioral and environmental factors, and medical history will be administrated. Anthropometric measurements and a series of laboratory tests will be peribrmed in one central laboratory. The DNA, plasma, and urine samples of every participant will be stored in a biobank for future research. Conclusions： INDEED study will provide essential information regarding the clinical phenotype and prognosis of patients with DKD in China and will be valuable to identity factors and biomarkers associated with patients with DKD in China.

Effect of Long-Term Systolic Blood Pressure Trajectory on Kidney Damage in the Diabetic Population： A Prospective Study in a Community-Based Chinese Cohort

Background：Previous studies have shown that hypertension is an important factor contributing to the occurrence and progression of diabetic kidney damage.However,the relationship between the patterns of blood pressure （BP） trajectory and kidney damage in the diabetic population remains unclear.This prospective study investigated the effect of long-term systolic BP （SBP） trajectory on kidney damage in the diabetic population based on an 8-year follow-up community-based cohort.Methods：This study included 4556 diabetic participants among 101,510 participants.BP,estimated glomerular filtration rate （eGFR）,and urinary protein were measured every 2 years from 2006 to 2014.SBP trajectory was identified by the censored normal modeling.Five discrete SBP trajectories were identified according to SBP range and the changing pattern over time.Kidney damage was evaluated through eGFR and urinary protein value.A multivariate logistic regression model was used to analyze the influence of different SBP trajectory groups on kidney damage.Results：We identified five discrete SBP trajectories：low-stable group （n =864）,moderate-stable group （n =1980）,moderate increasing group （n =609）,elevated decreasing group,（n =679）,and elevated stable group （n =424）.The detection rate of kidney damage in the low-stable group （SBP：118-124 mmHg） was the lowest among the five groups.The detection rate of each kidney damage index was higher in the elevated stable group （SBP：159-172 mmHg） compared with the low-stable group.For details,the gap was 4.14 （11.6% vs.2.8%） in eGFR 〈60 ml.min-1.1.73 m 2 and 3.66 （17.2% vs.4.7%）,3.38 （25.0% vs.7.4%）,and 1.8 （10.6% vs.5.9%） times in positive urinary protein,eGFR 〈60 ml.min-1.1.73 m 2 and/or positive urinary protein,and eGFR decline ≥30%,respectively （P 〈 0.01）.Conclusion：An elevated stable SBP trajectory is an independent risk factor for kidney damage in the diabetic population.

Anemia and insomnia: a cross-sectional study and meta-analysis

Background: Several recent genome-wide association studies suggested insomnia and anemia may share some common genetic components. We thus examined whether adults with anemia had higher odds of having insomnia relative to those without anemia in a cross-sectional study and a meta-analysis.Methods: Included in this cross-sectional study were 12,614 Chinese adults who participated in an ongoing cohort, the Kailuan Study. Anemia was defined as hemoglobin levels below 12.0 g/dL in women and 13.0 g/dL in men. Insomnia was assessed using the Chinese version of the Athens Insomnia Scale (AIS). A total AIS score ≥6 was considered insomnia. The association between anemia and insomnia was assessed using a logistic regression model, adjusting for potential confounders such as age, sex, chronic disease status, and plasma C-reactive protein concentrations. A meta-analysis was conducted using the fixed effects model to pool results from our study and three previously published cross-sectional studies on this topic in adult populations.Results: Individuals with anemia had greater odds of having insomnia (adjusted odds ratio [OR]: 1.32;95% confidence interval [CI]: 1.03-1.70) compared with individuals without anemia. A significant association persisted after we excluded individuals with chronic inflammation, as suggested by C-reactive protein levels >1 mg/L (adjusted OR: 1.68;95% CI: 1.22-2.32). The meta-analysis results, including 22,134 participants, also identified a positive association between anemia and insomnia (pooled OR: 1.39;95% CI: 1.22-1.57).Conclusions: The presence of anemia was significantly associated with a higher likelihood of having insomnia in adults. Due to the nature of the cross-sectional study design, results should be interpreted with caution.

Systemic-Related Factors of Nonarteritic Anterior Ischemic Optic Neuropathy

To the Editor： Nonarteritic anterior ischemic optic neuropathy （NAION） is an acute optic neuropathy disease that is common in the elderly. The incidence of NA1ON is approximately （2.3-10.2）/100,000, and both eyes are involved in many patients. Xu et al. reported that the incidence in the Chinese population was 1/16,000. Acute visual acuity （VA） damage without any pain and a poor prognosis are the main features of NAION. This study aimed to find the related risk factors for NAION in average individuals to promote the prevention or early diagnosis of NAION.

Relationship of sleep duration and annual changes in sleep duration with the incidence of gastrointestinal cancers:a prospective cohort study

Background:Prospective analyses have yet to identify a consistent relationship between sleep duration and the incidence of gastrointestinal(GI)cancers.The effect of changes in sleep duration on GI cancer incidence has scarcely been studied.Therefore,we aimed to examine the association between baseline sleep duration and annual changes in sleep duration and GI cancer risk in a large population-based cohort study.Methods:A total of 123,495 participants with baseline information and 83,511 participants with annual changes in sleep duration information were prospectively observed from 2006 to 2015 for cancer incidence.Cox proportional-hazards models were used to calculate hazard ratios(HRs)and their confidence intervals(CIs)for GI cancers according to sleep duration and annual changes in sleep duration.Results:In baseline sleep duration analyses,short sleep duration(≤5 h)was significantly associated with a lower risk of GI cancer in females(HR:0.31,95%CI:0.10-0.90),and a linear relationship between baseline sleep duration and GI cancer was observed(P=0.010),especially in males and in the>50-year-old group.In the annual changes in sleep duration analyses,with stable category(0 to-15 min/year)as the control group,decreased sleep duration(≤-15 min/year)was significantly associated with the development of GI cancer(HR:1.29;95%CI:1.04-1.61),especially in the>50-year-old group(HR:1.32;95%CI:1.01-1.71),and increased sleep duration(>0 min/year)was significantly associated with GI cancer in females(HR:2.89;95%CI:1.14-7.30).Conclusions:Both sleep duration and annual changes in sleep duration were associated with the incidence of GI cancer.