上海市大气污染与居民每日死亡关系的病例交叉研究

目的 以病例交叉的研究方法，估计大气污染急性暴露对上海市居民每日死亡的影响，并探讨该设计用于大气污染急性健康效应研究的可行性。方法 采用病例交叉设计的方法分析上海市2000年6月1日至2001年12月31日大气污染与居民每日总死亡和分疾病别死亡的关系，同时比较双向对照设计和单向回顾性对照设计研究结果的差异。结果 采用不同的对照选择方案，病例交叉设计的研究结果变化较大；采用双向1：6的对照设计，大气可吸入颗粒物(PMl0)、二氧化硫(SO2)、二氧化氮(NO2)48h平均浓度每增加10μg／m^3，上海市城区居民总死亡发生的相对危险度分别为1．003(95％CI：1．001～1．005)、1．016(95％CI：1．011～1．021)、1．020(95％CI：1．012～1．027)。结论 上海市城区目前的PMl0、SO2、NO2水平对居民死亡确有影响；病例交叉设计是一种研究大气污染急性健康效应的有效工具。     

Zolpidem Use and Risk of Fracture in Elderly Insomnia Patients

Objectives

To evaluate the risk of fractures related with zolpidem in elderly insomnia patients.

Methods

Health claims data on the entire South Korean elderly population from January 2005 to June 2006 were extracted from the Health Insurance Review and Assessment Service database. We applied a case-crossover design. Cases were defined as insomnia patients who had a fracture diagnosis. We set the hazard period of 1 day length prior to the fracture date and four control periods of the same length at 5, 10, 15, and 20 weeks prior to the fracture date. Time independent confounding factors such as age, gender, lifestyle, cognitive function level, mobility, socioeconomic status, residential environment, and comorbidity could be controlled using the casecrossover design. Time dependent confounding factors, especially co-medication of patients during the study period, were adjusted by conditional logistic regression analysis. The odds ratios and their 95% confidence intervals (CIs) were estimated for the risk of fracture related to zolpidem.

Results

One thousand five hundred and eight cases of fracture were detected in insomnia patients during the study period. In our data, the use of zolpidem increased the risk of fracture significantly (adjusted odds ratio [aOR], 1.72; 95% CI, 1.37 to 2.16). However, the association between benzodiazepine hypnotics and the risk of fracture was not statistically significant (aOR, 1.00; 95% CI, 0.83 to 1.21). Likewise, the results were not statistically significant in stratified analysis with each benzodiazepine generic subgroup.

Conclusions

Zolpidem could increase the risk of fracture in elderly insomnia patients. Therefore zolpidem should be prescribed carefully and the elderly should be provided with sufficient patient education.     

Alcohol Quantity and Type on Risk of Recurrent Gout Attacks: An Internet-based Case-crossover Study

Objectives

Although beer and liquor have been associated with risk of incident gout, wine has not. Yet anecdotally, wine is thought to trigger gout attacks. Further, how much alcohol intake is needed to increase the risk of gout attack is not known. We examined the quantity and type of alcohol consumed on risk of recurrent gout attacks.

Methods

We conducted a prospective Internet-based case-crossover study in the US among participants with gout and who had at least one attack during the 1 year of follow-up. We evaluated the association of alcohol intake over the prior 24 hours as well as the type of alcoholic beverage with risk of recurrent gout attack, adjusting for potential time-varying confounders.

Results

This study included 724 participants with gout (78% men, mean age 54 years). There was a significant dose-response relationship between amount of alcohol consumption and risk of recurrent gout attacks (P <.001 for trend). The risk of recurrent gout attack was 1.36 (95% confidence interval [CI], 1.00-1.88) and 1.51 (95% CI, 1.09-2.09) times higher for >1-2 and >2-4 alcoholic beverages, respectively, compared with no alcohol consumption in the prior 24 hours. Consuming wine, beer, or liquor was each associated with an increased risk of gout attack.

Conclusions

Episodic alcohol consumption, regardless of type of alcoholic beverage, was associated with an increased risk of recurrent gout attacks, including potentially with moderate amounts. Individuals with gout should limit alcohol intake of all types to reduce the risk of recurrent gout attacks.     

长沙市气温变化与急性脑血管疾病急诊关系的病例交叉研究

目的 探讨长沙市日均气温变化与急性脑血管疾病急诊的相关性.方法 收集2008-2009年长沙市每日急性脑血管疾病急诊数据及相关气象和大气污染数据,运用季节分层的病例交叉设计分析不同季节日均气温变化对总急性脑血管疾病及主要亚型[脑出血、脑梗死和短暂性脑缺血发作(TIA)]的影响.结果 同时控制相对湿度、气压和风速的多气象因素模型分析显示,春季日均气温每升高1℃,脑出血、脑梗死、TIA和总急性脑血管疾病急诊的OR值分别为1.278 (95％CI:1.045～ 1.563)、1.223(95％CI:1.056～1.416)、1.318(95％CI:1.099～1.581)和1.239(95％CI:1.085～1.414),关联均有统计学意义(P＜0.05);夏季日均气温每升高1℃,脑梗死和总急性脑血管疾病急诊的OR值为1.201 (95％CI:1.006～1.434)和1.179(95％CI:1.002～1.387),关联有统计学意义(P＜0.05),脑出血和TIA急诊的OR值大于1,但关联无统计学意义;秋季日均气温每升高1℃,脑出血、脑梗死、TIA和总急性脑血管疾病急诊的OR值分别为0.803 (95％CI:0.683～0.944)、0.765(95％CI:0.664～0.882)、0.794(95％CI:0.671～0.940)和0.792(95％CI:0.699～0.898),关联均有统计学意义(P＜0.05);冬季日均气温变化与上述疾病的发病关联均无统计学意义.结论 长沙地区春季气温升高是脑出血、脑梗死、TIA和总急性脑血管疾病的危险因素,夏季气温升高是脑梗死和总急性脑血管疾病的危险因素,秋季气温下降是脑出血、脑梗死、TIA和总急性脑血管疾病的危险因素.     

热浪与非意外死亡和呼吸系统疾病死亡的病例交叉研究

目的探讨北京市热浪对当地居民每日非意外死亡及呼吸系统疾病死亡人数的影响。方法运用病例交叉设计的基本方法,分析北京市1999年1月1日—2000年6月30日期间5次热浪对居民每日非意外死亡和呼吸系统疾病死亡人数的影响,同时研究其对慢性阻塞性肺病(COPD)死亡的影响。采用1∶1单向回顾性对照,选择死亡发生前第7天作为自身对照,分别计算不同长度的危险期时的OR值,以最高的OR值及其对应的危险期来反映每次热浪过程对每日非意外死亡及呼吸系统疾病死亡人数的影响、滞后天数及持续时间。结果研究期间共发生5次热浪。第1次持续9d,最高气温为38.8℃,平均湿度为46.7%,居民每日非意外死亡、呼吸系统疾病死亡和COPD死亡的OR值分别为1.442(95%CI:1.310～1.588),2.667(95%CI:1.893～3.756)和1.778(95%CI:1.182～2.674);第2次热浪持续3d,最高气温为36.8℃,平均湿度为61.0%,3种死因每日死亡的OR值分别为1.200(95%CI:0.973～1.480),3.000(95%CI:1.090～8.254)和3.333(95%CI:0.917～12.112);第3次热浪持续7d,最高气温为41.5℃,平均湿度为58.5%,3种死因每日死亡的OR值分别为2.135(95%CI:1.925～2.368),3.360(95%CI:2.450～4.608)和2.897(95%CI:1.899～4.418);第4次持续3d,最高气温为39.6℃,平均湿度为31.9%,3种死因每日死亡的OR值分别为1.464(95%CI:1.042～2.057),1.000(95%CI:0.375～2.664)和1.000(95%CI:0.290～3.454);第5次热浪持续4d,最高气温为37.4℃,平均湿度为42.0%,3种死因每日死亡OR值分别为和1.525(95%CI:1.099～2.118),2.000(95%CI:0.500～7.997)和2.000(95%CI:0.603～5.371)。结论热浪对居民死亡有影响,且存在滞后效应,非意外死亡影响的滞后期一般为2～3d,呼吸系统疾病包括COPD死亡的滞后期为2～5d;热浪过程中气温越高,湿度越高,对呼吸系统疾病死亡的影响越大。     

大气污染物与呼吸系统疾病急诊就诊关系的病例交叉研究

目的 分析大气污染急性暴露对呼吸系统疾病急诊人次的影响.方法 收集2004年1月1日至2005年12月31日北京大学第三医院急诊科呼吸系统疾病急诊资料和北京市环境监测中心大气污染物数据,应用时间分层的病例交叉设计研究方法进行数据分析,同时比较单向回顾性对照设计和双向对照设计研究结果的差异.结果 在调整气象因素并采用单向回顾性(多污染物)模型中,无滞后大气可吸入颗粒物(PM10)、二氧化硫(SO2)、滞后2 d二氧化氮(NO2)日平均浓度每增加10 μg/m3,呼吸系统疾病总急诊的OR值(95%CI)分别为1.010(1.005～1.014)、1.010(1.001～1.018)、0.996(0.983～1.009);双向对称性(多污染物)模型中,其相应OR值(95%CI)分别为1.002(0.998～1.005)、1.011(1.003～1.018)、1.012(1.001～1.022).采用不同对照选择方案,病例交叉设计的研究结果有变化.结论 区域内大气污染物暴露对居民呼吸系统疾病急诊人次有急性效应.     

Alcohol consumption as a trigger of recurrent gout attacks

Background

Alcohol consumption has long been considered a trigger for recurrent gout attacks; however, this hypothesis has not been formally tested.

Methods

We conducted an Internet-based case-crossover study to assess several putative risk factors, including alcohol consumption, thought to trigger recurrent gout attacks. Subjects who had an attack within the past year were recruited online and asked to provide access to medical records pertaining to their gout. Data were obtained on the amount and type of alcoholic beverage consumed on each day over the 2-day period before a gout attack and on each day over a 2-day period during the intercritical period. We examined the amount and type of alcohol consumption and the risk of recurrent gout attacks using a conditional logistic regression adjusting for diuretic use and purine intake.

Results

A total of 197 subjects were recruited online over a 10-month period. Of those, 179 (91%) fulfilled the American College of Rheumatology Criteria for gout. Compared with no alcohol consumption, odds ratios for recurrent gout attacks were 1.1, 0.9, 2.0, and 2.5 for 1 to 2, 3 to 4, 5 to 6, and 7 or more drinks consumed over the 2-day period, respectively (P<.005). A dose-response relationship of risk of gout attacks was more evident for alcohol consumed over the last 24 hours. An increased risk of recurrent gout attacks was found for each type of beverage consumed.

Conclusion

Alcohol consumption triggers recurrent gout attacks. This effect was likely to occur within 24 hours after its consumption.     

A Case-Crossover Study of Sleep and Work Hours and the Risk of Road Traffic Accidents

Study Objectives:

Sleepiness, prolonged wakefulness, and extended work hours have been associated with increased risk of injuries and road accidents. The authors'' objective was to study the relation between those factors and road accidents using a case-crossover design, effective in estimating the risk of acute events associated with transient, short effect exposures.

Design:

Five hundred seventy-four injured drivers presenting for care after road accidents to the Emergency Room of Udine, Italy, were enrolled in the study from March 2007 to March 2008. Sleep, work, and driving patterns in the 48 h before the accident were assessed through an interview.

Measurements and Results:

The relative risk (RR) of accident associated with each exposure was estimated using the case-crossover matched pair interval approach. Sleeping ≥ 11 h daily was associated with a decrease of the RR, as was sleeping less than usual. Being awake ≥ 16 h and, possibly, working > 12 h daily were associated with increases in the RR.

Conclusions:

Extended work hours and prolonged wakefulness increase the risk of road accidents and suggest that awareness should be raised among drivers. The findings regarding acute sleep amount are less clear, possibly due to an effect of chronic sleep loss.

Citation:

Valent F; Di Bartolomeo S; Marchetti R; Sbrojavacca R; Barbone F. A case-crossover study of sleep and work hours and the risk of road traffic accidents. SLEEP 2010;33(3):349-354.     

空气污染物与脑梗死发生情况的病例交叉研究

目的　采用病例交叉研究设计,分析空气污染物对脑梗死发生情况的影响。方法　收集2014-01-01至2016-12-31宁波市3家三级甲等医院（宁波市医疗中心李惠利医院、宁波市第一医院和宁波市第二医院）所有诊断为脑梗死的就诊记录（ICD10编码I63）,及宁波市环境监测中心的空气污染物数据、宁波市气象局的气温数据。采用单向回顾性1∶3配对病例交叉研究设计,建立单污染物和多污染物模型条件Logistic回归分析,并对性别进行亚组分析。结果　2014-01-01至2016-12-31宁波市3家三级甲等医院共计诊断脑梗死22 837人次,其中男10 968人次（占48.03%）,女7 540人次（占33.02%）,男女比例为1.45∶1,性别缺失4 329人次（占18.95%）。单污染物模型结果显示：NO2、CO浓度是发生脑梗死的影响因素〔OR=1.001,95%CI（1.000,1.003）,P=0.034;OR=0.794,95%CI（0.723,0.873）,P<0.001〕;性别亚组分析发现,NO2、O3浓度是男性发生脑梗死的影响因素〔OR=1.003,95%CI（1.001,1.004）,P=0.011;OR=0.999,95%CI（0.998,1.000）,P=0.033〕,NO2、CO浓度是女性发生脑梗死的影响因素〔OR=1.002,95%CI（1.000,1.005）,P=0.046;OR=0.826,95%CI（0.704,0.968）,P=0.018〕。多污染物模型结果显示：PM10、NO2、CO浓度是发生脑梗死的影响因素〔OR=1.001,95%CI（1.000,1.002）,P=0.019;OR=1.004,95%CI（1.002,1.006）,P<0.001;OR=0.564,95%CI（0.490,0.650）,P<0.001〕;性别亚组分析发现,PM10、NO2、O3、CO浓度是男性发生脑梗死的影响因素〔OR=1.002,95%CI（1.001,1.004）,P=0.004;OR=1.004,95%CI（1.001,1.007）,P=0.004;OR=0.999,95%CI（0.998,0.999）,P=0.001;OR=0.580,95%CI（0.474,0.708）,P<0.001〕;NO2、CO浓度是女性发生脑梗死的影响因素〔OR=1.006,95%CI（1.003,1.009）,P<0.001;OR=0.609,95%CI（0.480,0.773）,P<0.001〕。结论　在一定条件下,空气中的PM10、NO2浓度是发生脑梗死的危险因素,CO浓度是发生脑梗死的保护因素;部分空气污染物对脑梗死发生情况的影响存在性别差异。     

佳木斯市大气PM10对呼吸系统疾病日人院人数的影响

目的 探讨2010-2014年佳木斯市大气PM10对城区居民呼吸系统疾病日入院人数的影响.方法 采用1∶3配比的时间分层病例交叉研究,控制气象等因素的影响,以条件logistic回归分析佳木斯市2010年1月1日-2014年12月31日大气PM10浓度与呼吸系统疾病日入院人数的关系,并按性别(男、女)、年龄(＜15岁、15～65岁、＞65岁)和疾病类型[肺炎、慢性阻塞性肺疾病(COPD)和支气管肺炎],对大气污染物的健康效应进行分层分析.结果 研究期间佳木斯市大气PM10的日均浓度及年均浓度均低于国家二级标准.大气PM10日均浓度与SO2、NO2、日均气压呈正相关,与日均温度呈负相关,差异均有统计学意义(P＜O.01).单污染物模型显示,研究期间大气PM10浓度每升高10μg/m3,与肺炎、COPD日入院人数的OR值分别在滞后4、3d达到最高,相应的OR值(95％CI)分别为1.021(1.002～1.041),1.022(1.004～1.040),均有统计学意义(P＜0.05);在控制气温、相对湿度、气压的影响后,多污染物模型显示,大气PM10浓度每升高10 μg/m3,仍会增加肺炎、COPD日入院人数,均有统计学意义(P＜0.05).性别分层结果显示,大气PM10浓度每升高10 μg/m3,可引起男性肺炎患者及男、女性COPD患者日入院人数增加,差异均有统计学意义(P＜0.05);年龄分层结果显示,大气PM10浓度每升高10μg/m3,可引起＜15岁、15～65岁、＞65岁肺炎、COPD、支气管肺炎患者日入院人数增加,差异均有统计学意义(P＜0.05).结论 佳木斯市呼吸系统常见疾病的日入院人数增加可能与该市大气PM10短期低浓度暴露有关联.