慢性病对中老年人跌倒伤害影响的队列研究

目的:分析慢性病对我国中老年人跌倒伤害风险的影响。方法:数据来源于中国健康与养老追踪调查（CHARLS）,以2011年基线调查募集的13 670名≥45岁中老年人作为研究对象并追踪至2018年,其中45~59岁中年人7 443例（54.45%）,≥60岁老年人6 227例（45.55%）。采用Cox比例风险模型分析不同...     

北京城乡老年队列中基线痴呆的全死因死亡率及死亡风险研究

目的 通过对目标人群的追踪观察,探讨老年期痴呆的死亡率及死亡风险.方法 1997年采用按类分层、分阶段随机抽取区(县)、街道(乡)、居委会(自然村),按照整群抽样原则获得研究样本.分两阶段调查基线痴呆患病率,第一阶段完成问卷调查及筛查量表(MMSE)等测试,第二阶段由神经内科医师对MMSE得分低于界值和部分正常的老年人进行病史搜集、临床查体及神经心理测验等,最后由2名神经内科医师根据DSM-Ⅲ-R和NINCDS-ADRDA等诊断标准完成痴呆的临床诊断.最终获得有效调查样本2788例.在2000和2004年对研究样本进行全面随访同时记录死亡及失访原因和时间,总计随访7.25年.结果 基线共诊断痴呆171例,累积死亡133人.全样本的痴呆粗死亡率和年龄标化率分别为7.8/1000人年和5.5/1000人年,且随年龄的增加而呈指数增加;痴呆组其粗死亡率和年龄标化率分别为236/1000人年和206/1000人年;非痴呆组累积死亡680人,粗死亡率和年龄标化率分别为40/1000人年和31/1000人年,两组粗死亡率差异有统计学意义.痴呆的死亡风险比在60～74岁各组均高于≥75岁各组.经多因素Cox回归调整,痴呆的死亡风险比为2.181(95％CI:1.751～2.717)、阿尔茨海默病为2.524(95％CI:1.964～3.243)、血管性痴呆为1.859(95％CI:1.213～2.850).结论 老年期痴呆的粗死亡率及死亡风险比大大高于一般人群,提示痴呆是预示老年人死亡的最主要危险因素之一.     

不同剂量食盐加碘干预试验中人群尿碘的变化规律

目的 分析不同剂量食盐加碘干预后人群尿碘水平的变化规律及其影响因素.方法 采用多级整群随机抽样方法,抽取2个县(B县和Y县)中各3个乡镇居民研究对象,分别进行不同食盐加碘浓度(15±5、25±5、35±5)mg/kg的社区干预,观察干预后各人群的尿碘变化规律.结果 B县3个实验乡镇的尿碘水平随着干预时间逐渐下降,且以(15±5)mg/kg组下降较为明显,在6、12、18、24个月时分别为18000、18610、150 04、191 28 μg/L,符合WHO标准;(25±5)mg/kg组下降幅度次之,并在干预18个月时(187.96 μg/L)达到WHO标准;(35±5)mg/kg变动不大.Y县实验乡镇干预后尿碘略有下降,但均未达到WHO标准.两县甲状腺容积总体上由干预前3.65ml降至干预后的3.40ml,干预前后差异有统计学意义(x2=54.29,P<0.0001).结论 降低碘盐浓度可在一定程度降低尿碘水平,减少甲状腺肿大率.

Abstract：

Objective To analyze the change of urinary iodine in a cohort of intervention trial and to observe the role of different doses on salt iodization and related impact factors on nutritional condition of iodine. Methods Multistage cluster sampling was used to sample three townships in two counties for community intervention with different doses (15 ± 5, 25 ± 5, 35 ± 5)mg/kg. Results Compared to the (35 ± 5)mg/kg group, the urine iodine levels of three experimental townships were gradually declining in county B when time went on, and the (15 ± 5) mg/kg group showed anobvious results, at 6,12,18 and 24 months, with the urine iodine level as 180.00,186.10,150.04,191.28 μg/L respectively, which were in accordance with the WHO standard and reached to appropriate range (187.96μg/L) at the 18 month. The townships at county Y under intervention had declined slightly, but the urine iodine levels did not reach the WHO standard. The thyroid volume declined from 3.65 ml to 3.40 ml in two counties and the difference between them was statistically significant. Conclusion To some extent, reducing the iodine concentration in salt, had a role of lowering the urine iodine level and reducing the strumous rate.     

Outdoor temperature is associated with serum HDL and LDL

Background

While exposures to high and low air temperatures are associated with cardiovascular mortality, the underlying mechanisms are poorly understood. The risk factors for cardiovascular disease include high levels of total cholesterol and low-density lipoprotein (LDL), and low levels of high-density lipoprotein (HDL). We investigated whether temperature was associated with changes in circulating lipid levels, and whether this might explain part of the association with increased cardiovascular events.

Methods

The study cohort consisted of 478 men in the greater Boston area with a mean age of 74.2 years. They visited the clinic every 3–5 years between 1995 and 2008 for physical examination and to complete questionnaires. We excluded from analyses all men taking statin medication and all days with missing data, resulting in a total of 862 visits. Associations between three temperature variables (ambient, apparent, and dew point temperature) and serum lipid levels (total cholesterol, HDL, LDL, and triglycerides) were studied with linear mixed models that included possible confounders such as air pollution and a random intercept for each subject.

Results

We found that HDL decreased −1.76% (95% CI: from −3.17 to −0.32, lag 2 days), and −5.58% (95% CI: from −8.87 to −2.16, moving average of 4 weeks) for each 5 °C increase in mean ambient temperature. For the same increase in mean ambient temperature, LDL increased by 1.74% (95% CI: 0.07–3.44, lag 1 day) and 1.87% (95% CI: 0.14–3.63, lag 2 days). These results were also similar for apparent and dew point temperatures. No changes were found in total cholesterol or triglycerides in relation to temperature increase.

Conclusions

Changes in HDL and LDL levels associated with an increase in ambient temperature may be among the underlying mechanisms of temperature-related cardiovascular mortality.     

Repeated attempts using different strategies are important for timely contact with study participants

Objective

To study the effect of different mail- and phone-based strategies, along with patient- and research-related factors, on the time to contact with research participants.

Study Design and Setting

A prospective evaluation of a 12-week standardized protocol (embedded with two randomized trials of mail- and phone-based strategies) for contacting existing research participants for recruitment into a related study.

Results

Of 146 participants, 87 were eligible for contact via the standardized protocol, and 63 (72%) of these were successfully contacted within 12 weeks after multiple mail- and phone-based efforts. Using Cox proportional hazards regression analysis, the different mail and phone strategies showed no significant difference in the time to contact with participants. Of 34 patient- and research-related factors evaluated, only two were independently associated with time to contact among all 146 participants: (1) participants having their last visit conducted outside of the research clinic because of patient illness/condition had a longer time to contact and (2) those with a self-reported chronic fatigue history had a shorter time to contact.

Conclusion

Few patient characteristics and research-related factors accurately predict time to contact. Repeated attempts using different strategies are important for successful and timely contact with study participants.     

Medical record review to recover missing data in a Portuguese birth cohort: agreement with self-reported data collected by questionnaire and inter-rater variability

Objectives

To assess the yield of medical record review to recover missing data originally collected by questionnaire, to analyze the agreement between these two data sources and to determine interobserver variability in clinical record review.

Methods

We analyzed data from a birth cohort of 8,127 women who were consecutively recruited after giving birth from 2005-2006. Recruitment was conducted at all public maternity units of Porto, Portugal. We reviewed the medical records of 3,657 women with missing data in the baseline questionnaire and assessed agreement between these two sources by using information from participants with data from both sources. Interobserver variability was assessed by using 400 randomly selected clinical records.

Results

Data on pregnancy complications and maternal anthropometric parameters were successfully recovered. Agreement between the questionnaire and records in family history data was fair, particularly for cardiovascular disease [k = 0.27; 95% confidence interval (95%CI): 0.23-0.32]. The highest agreement was observed for personal history of diabetes (k = 0.82; 95%CI 0.70-0.93), while agreement for hypertension was moderate (k = 0.60; 95%CI 0.50-0.69). Discrepancies in prepregnancy body mass index classes were observed in 10.3% women. Data were highly consistent between the two reviewers, with the highest agreement found for gestational diabetes (k = 1.00) and birth weight (99.5% concordance).

Conclusion

Data from the medical records and questionnaire were concordant with regard to pregnancy and well-known risk factors. The low interobserver variability did not threaten the precision of our data.     

Developmental and environmental origins of breast cancer: DDT as a case study

More than 20 studies of serum "DDT" and breast cancer have found little support for the hypothesis that exposure influences risk of breast cancer. However, studies share common limitations including the inability to account for exposure in early life when the breast may be most vulnerable and the inability to measure exposure to the primary components of commercial DDT. This paper (1) summarizes evidence regarding critical windows of exposure for breast cancer (2) summarizes lessons learned from initial efforts to study DDT and breast cancer (3) reviews evidence from the Child Health and Development Studies (CHDS) where exposure was measured in young women using blood samples obtained during active exposure, 1-3 days after delivery and (4) suggests approaches for human studies that might advance understanding of environmental stressors in the developmental origins of disease.     

社区轻度认知功能障碍老年人认知减退转归结果分析

[目的]了解轻度认知功能障碍(MCI)向认知减退转归结局及转化率,为预防痴呆发生提供可控制方案。[方法]采用整群随机抽样方法调查社区65岁以上老年人6192人,根据DSM-IV标准,在基底人群中筛选600MCI对象,年龄±2岁、性别相同、文化程度一致的原则选取正常对照组,与MCI组进行1︰1匹配,按半年1次随访计划,完成3次随访。按照人年法计算发病密度及比较转化为认知减退RR和95%CI,采用Log-rank检验对每一指标不同水平随访对象认知减退转归比较。[结果]565对研究对象纳入研究,认知减退组人年发病密度14.70%(14.52%,15.29%),正常对照组3.75%(3.56%,3.67%),两组随访对象转化为认知减退结局的生存曲线经Log-rank检验差异有统计学意义(χ2=11.643,P﹤0.01)。[结论]MCI转化为认知减退结局的危险性远远大于认知正常受试者。提示对社区MCI人群早期干预可能对认知减退甚至老年痴呆预防起到重要作用。     

Fiber glass exposure and human respiratory system cancer risk: lack of evidence persists since 2001 IARC re-evaluation

Objective

To determine whether IARC’s 2001 decision to downgrade the classification of insulation glass wool from Group 2B to Group 3 remains valid in light of epidemiological evidence reported after 2001.

Methods

We performed a systematic review of epidemiological evidence regarding respiratory cancer risks in relation to man-made vitreous fiber (MMVF) exposure before and after the 2001 IARC re-evaluation with focus on glass wool exposure and respiratory system cancer.

Results

Since 2001, three new community-based, case-control studies, two detailed analyses of existing cohort studies and two reviews/meta-analyses were published. These studies revealed no consistent evidence of an increased respiratory system cancer risk in relation to glass wool exposure.

Conclusions

From our evaluation of the epidemiological evidence published since 2001, we conclude that IARC’s 2001 decision to downgrade insulation glass wool from Group 2B to Group 3 remains valid.     

Cortisol secretion and fatigue: Associations in a community based cohort

The association between fatigue and reduced activity in the hypothalamo-pituitary–adrenal (HPA) axis has been described. However the temporal association between fatigue and HPA activity is under debate. We examine whether alterations in cortisol secretion play a role in the development of fatigue or whether changes occur later as a consequence of fatigue in a longitudinal cohort study of 4299 community dwelling adults (mean age 61). Cortisol secretion was measured from saliva samples collected waking, waking + 0.5, 2.5, 8, 12 h and bedtime at phase 7 (2003–2004) of the Whitehall II study. Fatigue was measured at phase 6 (2001), phase 7 and phase 8 (2006) of the Whitehall II study. Three elements of secretion were examined: waking cortisol, the cortisol awakening response and diurnal slope in cortisol secretion. Fatigue was determined using the vitality sub-scale of the Short Form-36. A wide variety of co-variates were measured. We find that fatigue measured at phase 6 was not associated with cortisol secretion at phase 7. At phase 7, low waking cortisol levels and a flat slope in diurnal cortisol secretion were associated with fatigue independently of co-variates. In participants low or free of fatigue at phase 7 low waking cortisol and flatter slope in cortisol secretion were associated with new-onset fatigue at phase 8 (for example, odds ratio for lowest vs. highest tertile of waking cortisol 1.50; 95% confidence intervals, 1.08, 2.09 after adjusting for all co-variates). In conclusion, we find that low waking salivary cortisol and a flat slope in cortisol secretion is associated with fatigue. Cortisol is also associated with future onset of fatigue suggesting that changes in cortisol secretion are etiologic or occur early in the genesis of fatigue.