受低剂量慢性连续照射的居民白内障危险研究

目的调查并比较接受低剂量慢性连续照射的阳江高本底地区居民及其相邻对照地区居民的白内障患病率。方法在阳江高本底地区和对照地区各整群抽取3个村子和1个村子共194名年龄≥50岁的常住居民,进行问卷调查和白内障检查。采用logistic回归分析白内障与各种危险因素的关系。结果对性别、年龄进行调整之后,发现高本底地区居民患白内障、皮质性白内障、核性白内障、后囊下白内障的OR值分别为2.93(95%CI:1.19～7.17)、1.51(95%CI:0.15～15.24)、2.93(95%CI:1.20～7.17)和2.35(95%CI:0.59～9.42)。结论长期低剂量电离辐射受照是白内障发生的重要危险因素。     

矽肺对肺癌及总死亡影响的回顾性队列研究

目的 利用香港矽肺患者队列的资料进行分析,探讨矽尘、矽肺与肺癌的关系.方法 选择1981年1月1日至1998年12月31日期间在香港尘肺诊所登记的2789例男性矽肺病例为研究对象,取用同时期一般男性人群作为对照.用人年的方法估计各死因的标化死亡比(SMR),用Axelson's法间接调整吸烟的混杂影响.矽尘与肺癌的剂量-效应关系采用多因素p-spline平滑法模型来拟合最佳风险模型.结果 该组研究队列人数为2789,共观察24 992.6人年,失访率仅为2.9%.该队列主要工种为建筑工人(5 1.09%)和地下沉箱操作工人(37.54%).队列总死亡人数为853人,平均死亡年龄为(63.8±10.27)岁,整个队列中86例死于肺癌.全死因及全癌的SMR均明显上升,首位死因是呼吸道疾病,肺癌的5MR明显增加(SMR:1.69,95%CI:1.35～2.09).去除年龄、时期和吸烟的混杂因素的影响,矽肺对肺癌的相对危险度下降到1.12(95%CI:0.89～1.38).间接调整吸烟的混杂影响后建筑工人及地下沉箱工人肺癌的相对危险度分别为1.09(95%CI:0.82～1.42)和1.56(0.98～2.36).多因素p-spline平滑法风险模型分析显示,肺癌与累积呼吸性矽尘总量或平均矽尘浓度的关系无剂量-效应关系.结论 队列研究未发现接触矽尘或矽肺能增加肺癌死亡的危险,平滑法模型拟合的风险模型并不支持矽尘与肺癌死亡之间存在剂量-效应关系.     

山西省东南部地区居民食管癌危险因素的病例对照研究

目的探讨山西省东南部地区居民饮食、行为等各种影响因素与食管癌发生的关系。方法在山西省东南部地区, 采用以人群为基础的 1︰2 配对病例对照研究方法, 对 101 例食管癌患者和 202 例对照进行问卷调查, 采用单因素和多因素条件 Logistic 回归对所获资料进行分析。结果 BMI 指数过低 (OR = 2.85, 95%CI: 0.96～8.27)、吸烟 (OR =3.08, 95%CI: 0.94～10.03)、饮酒 (OR = 3.12, 95%CI: 1.16-8.68)、常吃咸鱼腊肉 (OR = 8.68, 95%CI: 2.12～35.48)、喜食烫食 (OR = 5.69, 95%CI: 2.20～14.75) 可能是食管癌的危险因素; 常吃肉蛋禽奶 (OR = 0.20, 95%CI: 0.08～0.49)可能是食管癌的保护因素。结论生活习惯和饮食习惯是本地区食管癌的主要危险因素之一, 应对其采取综合性的预防措施。     

输精管绝育术与肺癌死亡率的关系

目的：探讨输精管绝育术与肺癌的关系。方法:对盐亭县40-70岁男性进行三年回顾及两年随访调查，及队列内1：2肺癌病例对照研究。采用Poisson回归及条件Logistic回归进行资料进行分析。结果：绝育人群中，绝育不足10年者肺癌死亡危险明显于绝育20年以上者RR=0.17(95%CI:0.34-0.35)，随着绝育时年龄的增加肺癌死亡危险增加，和40岁后绝育者相比30-39岁、30岁以前绝育者相对危险分别为0.83（95％CI:0.02-0.36)、0.16（95%CI:0.08-0.34).1-2病历对照研究发现绝育年限、绝育时年龄对肺癌死亡无影响。结论：肺癌死亡率在绝育人群和未绝育人群间差异无显著性，但早期绝育可能有助于降低其死亡率。     

江苏省大丰市肺癌影响因素病例对照研究

目的探讨江苏省恶性肿瘤高发区大丰市肺癌发病的影响因素及其可能存在的交互作用。方法在大丰市进行以人群为基础、1:1匹配的肺癌病例对照研究,共调查肺癌病例和健康对照613对,通过面对面询问的方式填写调查表;采用单因素及多因素条件Logistic回归进行分析,对46个可能的肺癌影响因素,以及吸烟与饮酒、吸烟与饮茶、饮茶与饮酒之间的交互作用进行分析。结果单因素条件Logistic回归分析发现,吸烟、接触油烟、肺结核病史、饮酒、被动吸烟、江苏省启东县、海门县移民(启海移民)和性格忧郁等因素是大丰市肺癌发病的可能影响因素;调整可能混杂因素的多因素条件Logistic回归分析发现,吸烟、性格忧郁、接触油烟等为大丰肺癌的主要危险因素,相应调整OR值分别为3.198(95%CI=2.242～4.563),2.767(95%CI=1.572～4.872)和1.347(95%CI=1.007～1.800);而规律饮茶、洗晒储粮用具为该地区肺癌的保护因素,相应调整OR值分别为0.574(95%CI=0.400～0.824)和0.754(95%CI=0.573～0.993);交互作用分析则未发现明显的交互作用(P0.05)。结论吸烟、性格忧郁、接触油烟可明显增加大丰市人群的肺癌发病危险,规律饮茶、洗晒储粮用具等则对肺癌发病具有明显保护作用。     

长期火山环境暴露与癌症发病率

火山环境是否成为癌症发病的一个危险因素还不得而知。研究者调查研究2组人群,一组来自有火山活动的地区,另一组来自没有火山活动的地区。研究获得2组人群癌症发病率的资料,并评价相对危度和年龄标化率。总体来说,在评价了综合癌症患者和性别后,在火山活动地区癌症发病率相对较高。然而,在没有火山活动地区,消化道癌、呼吸道癌和胸内器官方面的癌症呈现出较高的发病率,主要为男性;在有火山活动的地区的男女性中呈现较高的唇癌、口腔癌、咽喉癌及女性乳腺癌发病率。2组人群相关危险因素评估在有火山活动的地区呈现某些器官癌症的高危险性,特别是唇癌、口腔癌、咽喉癌和乳腺癌,这可能是长期火山环境暴露的结果。     

中国居民高尿酸血症危险因素的Meta分析

目的 系统评价中国居民高尿酸血症的危险因素,为预防控制决策提供依据.方法 应用Meta分析方法,对我国20130-2008年间公开发表的有关高尿酸血症危险因素病例-对照研究的10篇文献资料进行定量综合分析;运用Review Manager4.2进行一致性检验,并且进行合并OR值和95%CI的计算.结果 各因素合并OR值分别为:体质指数OR=3.09(95%CI:1.08～8.83);高甘油三酯OR=2.19(95%CI:1.45～3.30);肥胖OR=1.91(95%CI:1.63～2.24);饮酒OR=1.85(95%CI:1.42～2.43);高血糖OR=1.38(95%CI:1.16～1.65);高血压OT=1.20(95%CI:1.03～1.39).结论 高尿酸血症发生的可能主要危险因素为体质指数、高甘油三酯、肥胖、饮酒、高血糖、高血压.     

河南省开封县肺癌危险因素的病例对照研究

[目的]探讨河南省开封县肺癌发病的危险因素。[方法]对开封县130例肺癌患者进行1︰1配对的病例对照研究。[结果]吸烟量(OR=2.477,OR95%CI:1.485～4.130)、偏好咸食(OR=2.259,OR95%CI:1.029～4.959)、内向型性格(OR=4.379,OR95%CI:1.108～17.315)、长期失眠(OR=6.486,OR95%CI:1.671～25.178)、好生闷气(OR=16.872,OR95%CI:4.135～68.841)是开封县居民肺癌发生的危险因素。[结论]要根据开封县肺癌发病的实际情况因地制宜的开展肺癌的防治工作。     

北京市寒潮天气对居民心脑血管疾病死亡影响的病例交叉研究

目的研究寒潮天气对北京市居民心脑血管疾病日死亡人数的影响。方法北京市居民死亡资料来自北京市疾病预防控制中心,气象资料来自北京城市气象研究所。运用病例交叉的设计思想,采用单向回顾性1∶1对照和双向对称性1∶2对照设计,分析北京市1998年1月1日—2000年6月30日期间6次寒潮天气与北京市城8区居民每日心血管疾病、急性心肌梗死和脑血管疾病死亡的关系。病例选取为冬季所有心脑血管疾病死亡病例,选取死亡发生前第7天和发生后第7天作为对照(或者死亡前、后第14天作为对照)。结果研究时间段内共出现6次寒潮,日最低气温下降明显且伴随有湿度下降和气压上升的第3次寒潮期间3种死因的双向对称性对照设计的滞后期均为0d,居民每日心血管疾病、急性心肌梗死、脑血管疾病死亡的OR值分别为1.500(95%CI:1.032～2.181),1.913(95%CI:1.066～3.432)、1.679(95%CI:1.139～2.474)。其他5次寒潮对心脑血管病人的死亡未见明显影响。结论研究期间北京地区的绝大多数寒潮天气未对居民心脑血管疾病的死亡产生明显影响;但是温度降幅大且伴随高气压的寒潮可能会造成心脑血管疾病死亡风险升高,值得关注。     

输精管绝育术与人群恶性肿瘤死亡率的关系

目的探讨输精管绝育术与恶性肿瘤死亡率的关系.方法采用三年一次性回顾结合两年随访调查的历史前瞻方法.收集四川盐亭县40～70岁男性的绝育及死亡等资料,比较绝育与未绝育人群恶性肿瘤死亡率.结果绝育人群恶性肿瘤死亡危险低于未绝育组,标化死亡率分别为7.01‰、5.53‰(u=2.53,P《0.05),年龄调整SMR=0.88(95%CI0.88-0.96).并且,食管癌、肝癌死亡危险也显著降低,年龄调整SMR分别为0.78(95%CI0.67-0.88)、0.76(95%CI0.57-0.94).绝育人群中,绝育时年龄与绝育年限在恶性肿瘤死亡中存在相乘模式的交互作用.结论输精管绝育术不增加人群恶性肿瘤死亡率.     

Cancer and non-cancer mortality among Inhabitants in the high background radiation area of Yangjiang, China (1979-1998)

The present study aimed to evaluate the effects of high background radiation (HBR) on mortality. A cohort of 31,604 men and women aged 30-74 y living in the study area in Guangdong Province, China, was followed during the period 1979-1998. The information on deaths and migrations of cohort members was collected by visiting study areas every 3-4 y. Cumulative external radiation dose, lagged by 2 y for leukemia and 10 y for cancer excluding leukemia, was estimated for each individual based on hamlet-specific indoor and outdoor doses, and gender- and age-specific house occupancy factors. The follow-up study accumulated 736,942 person-years at risk and ascertained 6,005 deaths, including 956 cancer deaths and 4,525 non-cancer disease deaths. Mean cumulative radiation doses from natural radiation in the HBR and control area residents were 84.8 mGy and 21.6 mGy, respectively. Mortality due to leukemia (15 deaths) or cancer excluding leukemia (941 deaths) was not related to cumulative radiation dose. The excess relative risk (ERR) Gy of cancer excluding leukemia was estimated to be -1.01 (95% CI: -2.53, 0.95). In site-specific analysis, liver-cancer mortality was inversely related to the cumulative dose (p=0.002). Note, however, that liver cancer is well known for its difficulty in accurate diagnosis. The ERR Gy of cancer excluding leukemia and liver cancer was 0.19 (95% CI: -1.87, 3.04). Non-cancer disease mortality was not related to cumulative radiation dose either. The cumulative HBR dose was not related to the mortality due to cancer or all non-cancer diseases among residents in Yangjiang HBR areas.     

广东阳江高本底辐射地区居民适应性反应机制研究

目的 通过检测广东阳江天然高本底辐射地区(high background radiation area,HBRA)和对照低辐射地区(control area,CA)居民晚期糖基化终产物受体(receptor for advanced glycation endproducts,RAGE)和钙结合蛋白S100A6 mRNA及蛋白的表达,研究HBRA居民适应性反应机制.方法 以HBRA及CA居民为研究对象,分别选取50～60岁健康无遗传疾病家族史的男性长住居民各53名,收集血液及痰液样品,逆转录PCR(RT-PCR)检测血细胞中RAGE和S100A6 mRNA的表达,Western Blotting方法 分析痰细胞中RAGE和S100A6蛋白的表达.热释光剂量计(thermo luminescent dosemeter,TLD)检测居民暴露水平的外照射剂量及评估年有效剂量.结果 CA和HBRA组的平均年有效剂量分别为1.95 mSv和6.24 mSv,HBRA组的剂量约为CA组的3倍.与CA组相比,HBRA组居民RAGE与S100A6 mRNA与蛋白的表达量均有明显下降:以β-肌动蛋白(β-actin)为内参,血细胞mRNA中,RAGE和S100A6在CA组的相对中位表达量分别为0.28和1.06;而在HBRA组中分别为0.16和0.79,以Wilcoxon秩和检验分析,两者差异有统计学意义(Z值分别为-2.587和-2.328,P<0.05).痰细胞总蛋白中,以β-actin为内参,RAGE和S100A6在CA组的相对中位表达量分别为2.98和2.25;而在HBRA组中分别为0.53和0.47,以Wilcoxon秩和检验分析,两者差异有统计学意义(Z值分别为-2.201和-2.366,P<0.05).结论 长期接受天然高本底辐射的人群中RAGE及S100A6的表达量降低,可能与HBRA居民的适应性反应及低癌症死亡率有关.     

阳江天然放射性高本底地区放射流行病学调查概况

笔者综合报道了１９７２～１９９０年广东阳江天然放射性高本底地区（ＨＢＲＡ）放射流行病学调查主要结果，用多种测试仪器测定了环境γ辐射，说明ＨＢＲＡ居民所受外照射年平均照射量率为３３０ｍＲ，全身内外照射年有效剂量当量为６．４ｍＳｖ，对照地区（ＣＡ）相应为１１４ｍＲ和２．４ｍＳｖ，对本底辐射以外环境和宿主的可能致癌与致突变因素的研究表明，两地区基本符合“齐同对比”原则，两人群是可比的，根据对ＨＢＲＡ１７     

Effect of smoking on chromosomes compared with that of radiation in the residents of a high-background radiation area in China

Cytogenetic investigation of stable-type aberrations (translocations) was carried out with our improved methods on 28 elderly individuals in a high-background radiation area (HBRA) in China, and on 24 elderly individuals in a control area (CA). The level of radiation in HBRA is 3 to 5 times higher than in CA. The mean frequencies of translocations per 1,000 cells in HBRA and CA were 12.4 +/- 5.3 and 10.0 +/- 3.8, respectively. No significant difference was found in the frequencies between HBRA and CA (P>0.05, Mann-Whitney U test). When elderly individuals in HBRA and CA were classified into four subgroups of HBRA nonsmokers, HBRA smokers, CA nonsmokers, and CA smokers, a significant difference was found in the frequencies between CA smokers and CA nonsmokers (P<0.05, Mann-Whitney U test). Furthermore a tendency of difference (a near T-value of 0.05 level) was found in a comparison of HBRA smokers vs. CA nonsmokers. The present results indicate that the elevated level of natural radiation in HBRA plays a less significant part than smoking in bringing about the induction rate of stable-type aberrations (translocations) in those areas.     

Radiation doses and cause-specific mortality among workers at a nuclear materials fabrication plant

A historical cohort mortality study was conducted among 6,781 white male employees from a nuclear weapons materials fabrication plant for the years 1947-1979. Exposures of greatest concern are alpha and gamma radiation emanating primarily from insoluble uranium compounds. Among monitored workers, the mean cumulative alpha radiation dose to the lung was 8.21 rem, and the mean cumulative external whole body penetrating dose from gamma radiation was 0.96 rem. Relative to US white males, the cohort experienced mortality deficits from all causes combined, cardiovascular diseases, and from most site-specific cancers. Mortality excesses of lung and brain and central nervous system cancers were seen from comparisons with national and state rates. Dose-response trends were detected for lung cancer mortality with respect to cumulative alpha and gamma radiation, with the most pronounced trend occurring for gamma radiation among workers who received greater than or equal to 5 rem of alpha radiation. These trends diminished in magnitude when a 10-year latency assumption was applied. Under a zero-year latency assumption, the rate ratio for lung cancer mortality associated with joint exposure of greater than or equal to 5 versus less than 1 rem of both types of radiation is 4.60 (95% confidence limits (CL) 0.91, 23.35), while the corresponding result, assuming a 10-year latency, is 3.05 (95% CL 0.37, 24.83). While these rate ratios, which are based on three and one death, respectively, lack statistical precision, the observed dose-response trends indicate potential carcinogenic effects to the lung of relatively low-dose radiation. There are no dose-response trends for mortality from brain and central nervous system cancers.     

The third analysis of cancer mortality among Japanese nuclear workers, 1991-2002: estimation of excess relative risk per radiation dose

The present study estimated excess relative risk per sievert (ERR/Sv) of cancer mortality among the cohort of 200?583 male Japanese nuclear workers, with an average individual cumulative dose of 12.2 mSv (<10 mSv, 75.4%; 100 + mSv, 2.6%), conducting Poisson regression using dose category specific observed and expected numbers of deaths, and average doses obtained from the official report of the Radiation Effects Association (REA) on the analysis of mortality of Japanese nuclear industry workers for 1991-2002, which reported the estimates of ERR/Sv for leukaemia but not for all cancers or any other cancer site. The possible confounding biases from drinking alcohol and smoking tobacco were evaluated by examining the association of cumulative radiation dose with the mortality of cancers related to drinking or smoking. For leukaemia (80 deaths), the estimate of ERR/Sv was - 1.93 (95% confidence interval (CI) = - 6.12, 8.57). For all cancers excluding leukaemia (2636 deaths), while the ERR/Sv was estimated to be 1.26 (95%CI = - 0.27, 3.00), confounding by alcohol consumption was suspected since the ERR/Sv estimate of alcohol-related cancers was 4.64 (95%CI = 1.13, 8.91) and the ERR/Sv estimate of all cancers excluding leukaemia and alcohol-related cancers was 0.20 (95%CI = - 1.42, 2.09). In conclusion, confounding by important lifestyle factors related to cancer risk may have a substantial effect on risk estimates, especially when conducting studies of low cumulative dose and, accordingly, low statistical power. Pooled analysis or meta-analysis of nuclear workers for solid cancers needs to take this point into account.     

External radiation exposure and mortality in a cohort of uranium processing workers

In a study of 2,514 White male workers employed between 1942 and 1966 at a US uranium processing plant, mortality was compared with overall US mortality, and the relation between external ionizing radiation and cancer was evaluated. Through 1993, 1,013 deaths occurred. The mean cumulative dose was 47.8 mSv. The standardized mortality ratio (SMR) was 0.90 for all causes of death and 1.05 for all cancers. Many cancer sites had elevated SMRs. Among nonmalignant outcomes, the SMR for chronic nephritis was 1.88 (six deaths observed). An excess relative risk estimate of 10.5 per Sv (10 cases) was observed for kidney cancer; this may have resulted from chance, internal radiation, or chemical exposures not considered.     

The mortality and cancer morbidity experience of workers at the Capenhurst uranium enrichment facility 1946-95.

The results presented here contain the follow-up of the cohort of workers ever employed at the Capenhurst site of British Nuclear Fuels plc or its predecessors between 1946 and 1995. The main activity of the plant is isotopic, 235U, enrichment of uranium. The study cohort consists of 12,540 employees and contains 334,473 person-years of follow up. This is a relatively mature cohort, with a mean follow-up period of 26.7 years, that has been exposed to low levels of radiation. The collective external radiation dose received by the 3244 radiation workers was 31.95 person-sieverts, with mean cumulative dose 9.85 mSv. To the end of 1995 there have been 3841 deaths recorded for this cohort, 585 of which were amongst radiation workers. The standardised mortality ratios (SMRs) for all causes were significantly low, 83 and 91 respectively, for radiation and non-radiation workers, indicating the usual 'healthy worker' effect. The cancer mortality was less than that expected, though not significantly so, with SMRs for all cancers of 88 and 97, for radiation and non-radiation workers respectively. The cancer registration rates were significantly low, with standardised registration ratios (SRRs) for all cancers of 82 and 88, for radiation and non-radiation workers respectively. An association between bladder cancer registrations and cumulative external radiation exposure was noted when the cumulative external dose was lagged by 20 years.     

The association of blood lead level and cancer mortality among whites in the United States

Lead is classified as a possible carcinogen in humans. We studied the relationship of blood lead level and all cancer mortality in the general population of the United States using data from the National Health and Nutrition Examination Survey II (NHANES II) Mortality Study, 1992, consisting of a total of 203 cancer deaths (117 men and 86 women) among 3,592 whites (1,702 men and 1,890 women) with average of 13.3 years of follow-up. We used Cox proportional hazard regression models to estimate the dose-response relationship between blood lead and all cancer mortality. Log-transformed blood lead was either categorized into quartiles or treated as a continuous variable in a cubic regression spline. Relative risks (RRs) were estimated for site-specific cancers by categorizing lead above and below the median. Among men and women combined, dose-response relationship between quartile of blood lead and all cancer mortality was not significant (ptrend = 0.16), with RRs of 1.24 [95% percent confidence interval (CI), 0.66-2.33], 1.33 (95% CI, 0.57-3.09), and 1.50 (95% CI, 0.75-3.01) for the second, third, and fourth quartiles, respectively, compared with the first quartile. Spline analyses found no dose response (p = 0.29), and none of the site-specific cancer RRs were significant. Among men, no significant dose-response relationships were found for quartile or spline analyses (p trend = 0.57 and p = 0.38, respectively). Among women, no dose-response relationship was found for quartile analysis (ptrend = 0.22). However, the spline dose-response results were significant (p = 0.001), showing a threshold effect at the 94th percentile of blood lead or a lead concentration of 24 microg/dL, with an RR of 2.4 (95% CI, 1.1-5.2) compared with the risk at 12.5 percentile. Because the dose-response relationship found in women was not found in men, occurred at only the highest levels of lead, and has no clear biologic explanation, further replication of this relationship is needed before it can be considered believable. In conclusion, individuals with blood lead levels in the range of NHANES II do not appear to have increased risk of cancer mortality.     

Age at exposure modifies the effects of low-level ionizing radiation on cancer mortality in an occupational cohort

In a cohort of 4,563 nuclear workers followed retrospectively from 1950 to 1994, we found that age at exposure modified the effects of external radiation dose on cancer mortality. Analyses involved application of conditional logistic regression to risk sets of age- and calendar time-matched cancer deaths, with covariates treated as time dependent and with cumulative radiation doses divided according to the age intervals in which exposure occurred. After adjustment for confounding factors, we found that workers exposed to external radiation after the age of 50 years experienced exposure-related elevations in mortality from cancer at any site [rate ratio (RR) = 1.98; 95% confidence interval (CI) = 0.63-6.26], radiosensitive solid cancer (RR = 3.29; 95% CI = 1.10-9.89), and lung cancer (RR = 3.89; 95% CI = 1.23-12.3) substantially greater (1.6- to 3.5-fold greater) than were seen in coworkers exposed at all earlier ages. In contrast, all of the radiation doses contributing to mortality from cancers of the blood and lymph system were received before age 50 (for age <50, RR = 2.73 and 95% CI = 1.46-5.10; for age > or =50, RR = 0.24 and 95% CI = 0.00-687). Our results for cancer of any site are consistent with the results of previous studies examining the effects of exposure age in nuclear workers. Thus, effects of low-level radiation doses may depend on exposure age, and furthermore, patterns of effect modification by age may differ by type of cancer.