先天性泌尿生殖系统结构畸形危险因素的研究

目的：探讨有关因素在先天性泌尿生系统结构畸形发病中的作用。方法：采用成组匹配的病列对照研究方法。对95例患先天性泌尿生殖系统 的围产儿和160例对照围产儿及其父母的情况进行调查。采用非条件logistic回归模型进行多因素分析,计算OR值及OR的95％可信限。结果：先天性泌尿生殖系统结构畸形多发生于男性围产儿（性别成比为74．7％,X^2＝74．863,P＝0．001）,多元逐步回归分析表明：母亲孕早、中期感冒（OR＝7．034,95％CI＝3．488－14．187）、低出生体重（OR＝4．075,95％CI＝1．774－9．362）、孕次≥2（OR＝3．133,95％CI＝1．514－6．483）及母亲孕前职业性接触有害化学物质（OR＝10．496,95％CI＝1．053－104．651）为先天性泌尿生殖系统结构畸形的危险因素,结论：胎儿男性别,母亲孕早、中期感冒、低出生体重,母亲孕次≥2及孕前职业性接触有害化学物质与胎儿发生先天性泌尿生系统畸形有关联。     

尿道下裂危险因素的病例对照研究

目的 探讨尿道下裂病因。方法 采用以医院为基础的1:2配比的病例对照研究方法,以统一的调查表及调查方式对107倒尿道下裂及214例对照进行面对面问卷调查,应用SAS 6.12软件对所有调查因素进行单因素及多因素logistic回归分析。结果 胎儿尿道下裂的发生与母亲孕前自然流产史(OR=3.87,95％CI:1.60～9.39)、孕期发生先兆流产(OR=3.57,95％CI:1.31～9.64)、孕早期感冒伴发热(OR=7.63,95％CI:2.50～23.24)、孕中期用抗感染和/或解热止痛药(OR=16.46,95％CI;3.46～78.21)、父亲职业性接触农药(OR=3.70,95％CI:1.49～9.16)及胎儿低出生体重(OR=12.62,95％CI:2.97～53.67)呈正相关,与母亲孕早期增加蛋白质类营养(OR=0.33,95％CI:O.15～0.74)呈负相关。结论 母亲孕前自然流产史、孕期发生先兆流产、孕早期感冒伴发热、孕中期用抗感染和/或解热止痛药、父亲职业性接触农药、胎儿低出生体重等可能增加胎儿发生尿道下裂的危险,而母亲孕早期增加蛋白质类营养可能降低胎儿发生尿道下裂的危险。     

贲门癌危险因素病例对照研究

目的：探讨贲门癌发生的危险因素，为深入进行病因学研究提供线索。方法：对福州市6所医院2000年和2001年4月至7月的住院病人603例进行多组病例对照研究。贲门癌组为病理、手术和胃镜确诊的贲门癌191例，非贲门部胃癌190例，健康对照组为与肿瘤病例同期住院的骨科、泌尿外科的非肿瘤病人222例。采用统一调查表进行床边询问，对资料进行单因素及多因素Logistic分析。结果：贲门癌的主要危险因素有一一级亲属患肿瘤（OR＝4．286 95％CI：2．431－7．554）、进食速度快（OR＝2．028 95％ CI：1．142－2．912）、三餐不按时吃（OR＝1．909 95％ CI：1．396－2．610）、饮用井水（OR＝1．741 95％CI：1．042－2．910）每日吸烟量多（OR＝1．347 95％CI：0．989－1．835）。主要保护 因素有：常吃新鲜水果（OR＝0．645 95％CI：0．439－0．945）、使用冰箱年数长（OR＝0．731 95％CI：0．536－0．997）、化程度高（OR＝0．468 95％CI：0．276－0．74）。结论： 贲门癌与非贲门部胃癌可能有不同的危险因素，值得进一步研究。     

男性不育症危险因素的病例对照研究

目的：探讨男性不育症的危险因素，方法：对94对病例和对照1：1配比进行病例对照研究。结果：长期大量吸烟（OR＝3．45，95％ CI：1．95－6．10）、婚外性生活史（OR＝7．29，95％CI：2．54－20．89）、高温大棚蔬菜种植（OR＝6．73，95％CI：1．91－23．69）、苯类化学品接触（OR＝20．53，95％CI：4．67－90．25），解脲支原体感染（OR＝5．55，95％CI：2．8－13．533）与男性不育症有关联，为其危险因素，结论：男性不育症是由多种因素长期反复作用的结果，其预防应从整治环境污染，加强职业防护，提高自我防护能力，改变不良工作生活习惯等方面做起。     

MTHFR基因、CBS基因、环境因素与先天性心脏病的病例对照研究

目的 探讨父母亚甲基四氢叶酸还原酶（MTHFR）基因C677T、胱硫醚β-合酶（CBS）基因T833C、环境因素与子代先天性心脏病（CHD）发生之间的关联。方法 采用1：1配对病例对照研究方法，分析115对CHD患儿与对照儿父母的环境暴露因素，并检测其MTHFR与CBS基因型，对CHD可能的危险因素进行单因素及多因素条件logistic回归分析。结果 母亲怀孕早期接触农药（OR=8．62）、妊娠合并症（OR=2．069）、孕早期感冒（OR=4．125）、孕期情绪状况（OR=4．653）、母亲MTHFR基因677TT型（OR=3．872）共5个因素为予代发生CHD的危险因素。结论 母亲MTHFR基因677TT型与子代CHD发生有关，未发现父母CBS基因T833C与子代CHD存在关联，母亲怀孕早期接触农药、妊娠合并症、孕早期感冒、孕期情绪紧张或忧郁可能增加子代发生CHD的危险。     

尿石症危险因素人群病例对照研究

目的 探索尿石症发病的危险因素，为人群预防提供依据。方法 选取深圳市尿石症现况调查发现的334例患者为病例组，721名健康者为对照组，进行尿石症危险因素人群病例对照研究；采用非条件logistic回归对34个变量进行分析，采用Falconer回归法估算遗传变。结果 尿石症病例组和对照组配比条件均衡可比，单因素logistic回归分析共有17个变量有统计学意义，但最终进入模型的因素有10个，其中4个变量为尿石症发病危险因素，OR值大小依次为既往泌尿系慢性炎症史（OR＝4.09,95%CI:1.38-12.14)，一级亲属尿石症史（OR＝2.61,95%CI:1.70-4.01)和多食动物蛋白质（OR＝2．14，95％CI：1．71－2．69），暴露日照时间长（OR＝1．39，95％CI：1．16－1．66）；而较高文化程度（OR＝0．46，95％CI：0．29－0．73），日引水量多（OR＝0．59，95％CI：0．48－0．72），饮果汁（OR＝0．41，95％CI：0．18－0．94），多食奶及奶制品（OR＝0．82，95％CI：0．68－0．99），多食蔬菜（OR＝0．70，95％CI：0．55－0．91）和多食水果（OR＝0．78，95％CI：0．64－0．94）6个变量为尿石症发病的保护因素。一级亲属尿石症患病率病例组高于对照组，尿石症分离比为0．0109，95％CI：0．0050－0．0168，一级亲属尿石症的遗传度为28．48％，男，女分别为32．06％和24．60％。结论 尿石症主要受饮食习惯影响，尿石症家族史和社会经济状况也与发病有关。     

影响准分子激光角膜原位磨镶术后屈光度欠矫的多因素分析

目的：探讨各种因素与准分子激光角膜原位磨镶术（LASIK）后屈光度欠矫的关系。方法：对行LASIK的近视患者696例中屈光度欠矫病例，按年龄、性别、职业、住址、近视时间、家族史以及手术前后全部检查资料分左右眼两组进行单因素χ^2检验和多因素logistic回归分析。结果：多因素条件logistic回归分析显示，左、右眼两组均与4种因素有关：近视时间（左眼组OR＝1．076，95％CI：1．030－1．124；右眼组OR＝1．093，95％CI：1．046－1．142）、近视屈光度（左眼组OR＝7．799，95％CI：1．755－34．654；右眼组OR－28．823，95％CI：5．750－144．467）、术前矫正视力（左眼组OR＝0．000，95％CI：0．000－0．262；右眼组OR＝0．000，95％CI：0．000－0．144）和角膜厚度（左眼组OR＝0．976，95％CI：0．965－0．987；右眼组OR＝0．975，95％CI：0．965－0．986）。结论：近视时间长，近视屈光度大是LASIK术后屈光度欠矫的危险因素；术前矫正视力好，角膜厚度厚是LASIK术后屈光度欠矫的保护因素。     

儿童腹股沟疝发病危险因素的配对病例-对照研究

目的探讨儿童腹股沟疝发生的主要危险因素。方法采用l：1配对病例一对照研究方法，对201例0-6岁腹股沟疝患儿与对照儿童的父母进行问卷调查，采用条件Logistic回归对所收集资料进行单因素及多因素分析．计算OR值及0R值的95％CI。结果多因素分析结果表明，儿童便秘史（OR=3．520，95％CI：1．238。10．015）、啼哭不安史（OR：6．532．95％CI：2．651～16．091）、母亲孕前1个月和孕期前3个月腌制品摄入史（彻=2．529，95％CI：1．271．5．031）及贫血史（DR：6．809，95％CI：2．530~18．322）、儿童腹股沟疝家族史（OR=11．250，95％CI：4．766～26．553）与儿童腹股沟疝的发病存在显著联系。结论儿童便秘史、儿童啼哭不安史、腹股沟疝家族史、母亲孕前1个月和孕期前3个月贫血史及腌制品摄人史是儿童腹股沟疝发生的危险因素。     

职业性铅暴露对女性生殖功能影响的Meta分析

目的：综合分析职业性铅暴露与女性生殖功能之间的关系,为制订防制措施提供科学依据。方法：通过计算机和手工检索,收集国内发表的关于职业性铅暴露与女工生殖功能关系的文献,按纳入和剔除标准严格筛选,采用Meta分析合并文献效应值,并进行一致性检验及发表偏倚检验。结果：共纳入17篇文献,职业性铅暴露与女性痛经关系的合并OR值（95% CI）为3．38（1．45,7．87）、周期异常的合并OR值（95％CI）为2．37（1．95,2．88）,先兆流产的合并OR值（95% CI）为4．24（2．19,8．22）,妊娠高血压的合并OR值（95％CI）为3．37（1．09—10．44）,死产死胎的合并OR值（95％CI）为3．90（2．43,6．56）,自然流产的合并OR值（95％CI）为3．10（2．17,4．43）,新生儿低体重的合并OR值（95％CI）为4．47（2．78,7．21）,畸形的合并OR值（95％CI）为3．63（2．12,6．22）。结论：女工职业性铅暴露可影响其生殖功能,应对其进一步采取保护措施。     

非胰岛素依赖型糖尿病视网膜病变危险因素的探讨

目的：采用1：1配比的病例对照研究对DR患病的危险因素进行了初步探讨。方法：采用条件Logistic回归分析程序对105名DR病例和对照进行分析。结果：单因素分析显示：糖尿病病程,糖尿病诊断年龄,高血压,SBP,尿蛋白,使用胰岛素治疗与糖尿病视网膜病变有关。经多因素分析进入主效应模型的因素为病程,其OR＝2．32（95％CI：1．32－4．5）;SBP,其OR＝4．78（95％CI：1．83－12．52）;尿蛋白,其OR＝1．9％（95％:1．21－2．99）;胰岛素使用量,其OR＝1．98（95CI：1．05－3．74）。吸烟,饮酒,饮茶,运动锻炼,社会经济状况,看书时间,社会心理因素以及BMI与DR无关。结论：在糖尿病人群中,DR发生的危险因素为病程长,使用胰岛素治疗,尿蛋白增高和SBP增高。     

Spontaneous abortion and maternal work in greenhouses

BACKGROUND: A positive association between maternal occupational exposure to pesticide and spontaneous abortion has been reported in some studies. Work in greenhouses may imply exposure of pregnant women to pesticides continuously and at elevated level. METHODS: A total of 717 women working in greenhouses provided information on 973 pregnancies, including 110 spontaneous abortions. These pregnancies were classified as exposed or not exposed according to maternal occupation, re-entry activities and application of pesticides in greenhouses during at least 1 month in the first trimester of pregnancy. The ORs for spontaneous abortion were estimated through a generalised estimate equations model for all orders of pregnancy together, and through a logistic regression model limited to first pregnancies. RESULTS: Increased risks of spontaneous abortion were found for maternal re-entry activities within 24 hr after pesticides were applied (all orders of pregnancy: OR 3.2, 95% CI 1.3-7.7; first pregnancies: OR 3.8, 95% CI 1.0-13.9) and for those who applied pesticides (all orders of pregnancy: OR 2.6, 95% CI 1.0-6.6; first pregnancies: OR 3.7, 95% CI 0.7-20,6) CONCLUSIONS: The observed results support the hypothesis of an association between maternal work in greenhouses and spontaneous abortion. The main limitations of the study are lack of information on the specific chemicals used and the small number of pregnancies heavily exposed to pesticides.     

Maternal, delivery, and perinatal characteristics associated with cryptorchidism: a population-based case-control study among births in Washington State

BACKGROUND: The etiology of cryptorchidism is largely unknown. To identify maternal, perinatal, and delivery characteristics associated with cryptorchidism at birth, we conducted a population-based case-control study using Washington State birth certificates linked to birth hospitalization records. METHODS: We identified 2,395 cases of cryptorchidism among male infants born in Washington State during 1986-1996, and, for comparison, we randomly selected four controls per case (N = 9,580), frequency-matched by year of birth. RESULTS: Infant characteristics associated with cryptorchidism included low birth weight (OR = 1.5; 95% CI = 1.3-1.8), small size for gestational age (OR = 1.9; 95% CI = 1.6-2.2), and breech presentation (OR = 1.7; 95% CI = 1.4-2.1). In addition to cryptorchidism, cases were more likely to have another type of congenital malformation (OR = 3.7; 95% CI = 3.2-4.2), particularly digestive (OR = 6.8; 95% CI = 3.7-12.7) or genitourinary (OR = 4.1; 95% CI = 3.0-5.6). Maternal and pregnancy characteristics associated with cryptorchidism included nulliparity (OR = 1.2; 95% CI = 1.1-1.3), maternal smoking during pregnancy (OR = 1.2; 95% CI = 1.1-1.4), and the following pregnancy complications: oligohydramnios (OR = 1.8; 95% CI = 1.3-2.6), placental abnormality (OR = 1.3; 95% CI = 1.0-1.8), and pregnancy-induced hypertension (OR = 1.6; 95% CI = 1.4-1.9). Odds ratios were similar when the analysis was restricted to term infants. CONCLUSIONS: These findings suggest that factors affecting fetal growth and development may increase the risk of cryptorchidism.     

Parental occupational exposure to pesticides and childhood germ-cell tumors

In a recently completed US case-control study (Children's Oncology Group, 1993-2001) with 253 cases and 394 controls, the authors investigated the association between parental occupational exposure to pesticides and risk of childhood germ-cell tumors. Information on occupational pesticide exposure was collected using job-specific module questionnaires and assessed by an experienced industrial hygienist. Odds ratios for childhood germ-cell tumors associated with maternal exposures before pregnancy, during pregnancy, and after the birth of the index child were 1.0 (95% confidence interval (CI): 0.8, 1.4), 1.1 (95% CI: 0.7, 1.6), and 1.3 (95% CI: 0.9, 1.8), respectively. Paternal exposures before pregnancy, during pregnancy, and after the birth of the index child were not related to germ-cell tumors (odds ratios (ORs) were 0.9 (95% CI: 0.7, 1.2), 0.8 (95% CI: 0.5, 1.2), and 0.8 (95% CI: 0.5, 1.3), respectively). When both parents had ever been occupationally exposed to pesticides before the index pregnancy, the odds ratio was 0.8 (95% CI: 0.4, 1.3). Subgroup analyses showed a positive association between maternal exposure to herbicides during the postnatal period and risk of germ-cell tumors in girls (OR = 2.3, 95% CI: 1.0, 5.2) and an inverse association between paternal exposure to pesticides during the index pregnancy and germ-cell tumors in boys (OR = 0.2, 95% CI: 0.1, 1.0). This study did not provide strong evidence supporting a relation between parental pesticide exposure in the workplace and risk of germ-cell tumors among offspring.     

重庆市0～5岁儿童出生缺陷疾病1∶2配对病例对照研究

目的:探讨重庆市儿童出生缺陷疾病发生的危险因素,评估其危险度,为制定出生缺陷干预措施、做好优生优育提供科学依据。方法:采用1:2配对病例对照研究,对165例病例、330例对照进行调查;使用SAS9.2统计软件进行统计分析,主要采用描述性分析、单因素分析logistic回归分析和多因素1:2匹配条件logistic回归分析方法。结果:有统计学意义的调查因素有:母亲妊娠期先兆流产(OR=80.60)、妊娠合并症(OR=13.06)、母亲家族遗传史(OR=63.40)、父亲患有慢性病(OR=13.01)、父亲饮酒(OR=3.52)、父亲职业有害接触(OR=10.37)、参加婚前检查(OR=0.37)、服用叶酸类药物(OR=0.30)、妊娠期吃鱼虾类食品(OR=0.18)。结论:母亲家族遗传史、妊娠期出现先兆流产、有妊娠合并症、父亲患有慢性病、父亲饮酒、父亲职业有害接触是导致出生缺陷发生的危险因素;参加婚前检查、服用叶酸类药物、妊娠期多吃鱼虾类食品是防止出生缺陷发生的保护因素。     

Risk factors for early infant mortality in Sarlahi district, Nepal

OBJECTIVES: Early infant mortality has not declined as rapidly as child mortality in many countries. Identification of risk factors for early infant mortality may help inform the design of intervention strategies. METHODS: Over the period 1994-97, 15,469 live-born, singleton infants in rural Nepal were followed to 24 weeks of age to identify risk factors for mortality within 0-7 days, 8-28 days, and 4-24 weeks after the birth. FINDINGS: In multivariate models, maternal and paternal education reduced mortality between 4 and 24 weeks only: odds ratios (OR) 0.28 (95% confidence interval (CI) = 0.12-0.66) and 0.63 (95% CI = 0.44-0.88), respectively. Miscarriage in the previous pregnancy predicted mortality in the first week of life (OR = 1.98, 95% CI = 1.37-2.87), whereas prior child deaths increased the risk of post-neonatal death (OR = 1.85, 95% CI 1.24-2.75). A larger maternal mid-upper arm circumference reduced the risk of infant death during the first week of life (OR = 0.88, 95% CI = 0.81-0.95). Infants of women who did not receive any tetanus vaccinations during pregnancy or who had severe illness during the third trimester were more likely to die in the neonatal period. Maternal mortality was strongly associated with infant mortality (OR = 6.43, 95% CI = 2.35-17.56 at 0-7 days; OR = 11.73, 95% CI = 3.82-36.00 at 8-28 days; and OR = 51.68, 95% CI = 20.26-131.80 at 4-24 weeks). CONCLUSION: Risk factors for early infant mortality varied with the age of the infant. Factors amenable to intervention included efforts aimed at maternal morbidity and mortality and increased arm circumference during pregnancy.     

Folic acid supplements modify the adverse effects of maternal smoking on fetal growth and neonatal complications

Maternal smoking during pregnancy leads to increased risks of neonatal complications. The use of folic acid supplements might reduce the adverse effects of smoking. We examined whether folic acid supplement use modifies the associations of maternal smoking with first trimester plasma homocysteine concentrations, fetal growth characteristics, and risks of neonatal complications. The associations were studied in 6294 mothers participating in a prospective population-based cohort study in The Netherlands. Main outcomes measurements were first trimester plasma homocysteine concentrations, fetal growth characteristics, and neonatal complications, including preterm birth, low birth weight, and small-size-for-gestational-age. Continued maternal smoking was associated with higher first trimester plasma homocysteine concentrations [difference 0.52 μmol/L (95% range = 0.20, 2.14)], lower third trimester fetal weight (difference -44 g (95% CI = -57, -31)], and birth weight [difference -148 g (95% CI = -179, -118)]. There were significant interactions between maternal smoking and folic acid supplements on all outcome measures (all P-interaction < 0.040). Among mothers who continued smoking during pregnancy, those who did not use folic acid supplements had the highest risk of delivering a child with low birth weight [OR = 3.45 (95% CI = 1.25, 9.54)] compared to those who did use periconceptional folic acid supplements. No significant effects were observed for the risks of preterm birth and small-size-for-gestational-age at birth. Our results suggest that some adverse effects of maternal smoking on fetal growth and neonatal outcomes might be reduced by the use of folic acid supplements. The observed interaction seems to be mainly driven by smoking in the first trimester only.     

Maternal diet and the risk of hypospadias and cryptorchidism in the offspring

Male genital tract birth defects have been associated in previous studies with several prenatal exposures to environmental and dietary risk factors. The purpose of this study was to explore the association between hypospadias and cryptorchidism, and the dietary habits of an agricultural population in Italy. A population-based case-control study was conducted in the Sicilian Province of Ragusa. Cases (n = 90) and controls (n = 202) included births for the period 1998-2002. Data on dietary habits of the mothers, as well as health-related social, occupational and environmental exposures prior to and during the index birth, were collected through interviews. Adjusted odds ratios (OR) were calculated by logistic regression after adjustment for confounding variables. Increased ORs were observed for mothers of children with hypospadias who, during pregnancy, frequently consumed fish (OR = 2.33 [95% confidence interval (CI) 1.03, 5.31]) and market-purchased fruit (OR = 5.10 [95% CI 1.31, 19.82]). For cryptorchidism, increased risk was observed in mothers consuming liver (OR = 5.21 [95% CI 1.26, 21.50]), and smoked products (OR = 2.46 [95% CI 1.15, 5.29]). For the two malformations pooled together, increased risk was associated with maternal consumption of liver (OR = 4.38 [95% CI 1.34, 14.26]) and with frequent consumption of wine (OR = 1.98 [95% CI 1.01, 3.86]). This study suggests that some maternal dietary factors may play a role in the development of congenital defects of the male reproductive tract. In particular, our data indicate that further research may be warranted on the endocrine-disrupting effects resulting from the bioaccumulation of contaminants (fish, liver), pesticides (marketed fruit, wine) and/or potentially toxic food components (smoked products, wine, liver).