Pieper C F, Rao K M, Currie M S, Harris T B, Cohen H J
Center for the Study of Aging and Human Development, Department of Community and Family Health, Duke University Medical Center, Durham, North Carolina 27710, USA.
J Gerontol A Biol Sci Med Sci. 2000 Nov;55(11):M649-57. doi: 10.1093/gerona/55.11.m649.
Dysregulation of immunologic and coagulation systems is common in elderly persons and is associated with many diseases of aging. Thrombotic events are a major cause of morbidity and mortality in the elderly population. This study assesses whether D-dimer, a marker of fibrinolytic activity, varies systematically by demographic, health, and functional measures, and derives a prediction model for factors related to D-dimer in a sample of community-dwelling elderly persons.
D-dimer levels were assessed in a random sample of 1,727 community-dwelling elderly persons from five rural and urban counties in North Carolina in 1992, as part of the Established Populations for the Epidemiologic Studies of the Elderly (Duke University). All subjects were 72 years or older at the time of the blood draw. In addition, all subjects were surveyed yearly by telephone or in person each year from 1986 to 1992 for a variety of health, functional, and social factors. Levels of D-dimer in 1992 were related cross-sectionally to demographics (age, race, education, income, gender, smoking), function (Nagi, Rosow-Breslau, Katz, Older Americans Resources and Services procedures instrumental activities of daily living), life satisfaction and self-rated health, self-reported diseases (heart attack, cancer, stroke, diabetes, and hypertension), and weight change from 1986 to 1992.
D-dimer levels increased with increasing age and functional disability. Among the health variables, only high blood pressure was predictive of D-dimer level. D-dimer levels were dramatically higher in blacks. Blacks were nearly four times more likely to have an extreme value of D-dimer (>600 microg/l) than whites when high D-dimer (yes/no) was analyzed, and blacks had an average level that was nearly 40% higher than whites in analyses of the continuous version of the outcome. This racial effect was not substantively affected in multivariable analyses with demographic and socioeconomic variables controlled. Race, age, functional status, current smoking, high blood pressure, and weight loss were related to level of D-dimer, and race, age, and functional status were related to the presence of a high D-dimer level (in the top 10% of the sample).
Black, older, and functionally impaired persons had significantly higher levels of D-dimer in this sample of community-dwelling elderly persons. The findings for race were particularly striking and persisted even after controlling for smoking and other factors known to be related to thrombosis and were not mediated by social factors. This result may contribute to our understanding of the increased levels of thrombotic events found in these groups.
免疫和凝血系统失调在老年人中很常见，并且与许多衰老相关疾病有关。血栓形成事件是老年人群发病和死亡的主要原因。本研究评估作为纤溶活性标志物的D - 二聚体是否会根据人口统计学、健康和功能指标而系统变化，并在一组社区居住的老年人样本中推导与D - 二聚体相关因素的预测模型。
1992年，作为老年人流行病学研究既定人群（杜克大学）的一部分，对来自北卡罗来纳州五个城乡县的1727名社区居住老年人的随机样本进行了D - 二聚体水平评估。所有受试者在抽血时年龄均在72岁及以上。此外，从1986年到1992年，每年通过电话或亲自对所有受试者进行调查，询问各种健康、功能和社会因素。1992年的D - 二聚体水平与人口统计学特征（年龄、种族、教育程度、收入、性别、吸烟情况）、功能（纳吉、罗索 - 布雷斯劳、卡茨、美国老年人资源与服务程序日常生活工具性活动）、生活满意度和自我评定健康状况、自我报告的疾病（心脏病发作、癌症、中风、糖尿病和高血压）以及1986年至1992年的体重变化进行横断面关联分析。
D - 二聚体水平随年龄增长和功能残疾程度增加而升高。在健康变量中，只有高血压可预测D - 二聚体水平。黑人的D - 二聚体水平显著更高。在分析高D - 二聚体（是/否）时，黑人出现D - 二聚体极值（>600微克/升）的可能性几乎是白人的四倍，在对连续型结果的分析中，黑人的平均水平比白人高出近40%。在控制了人口统计学和社会经济变量的多变量分析中，这种种族效应没有受到实质性影响。种族、年龄、功能状态、当前吸烟情况、高血压和体重减轻与D - 二聚体水平相关，种族、年龄和功能状态与高D - 二聚体水平（样本中排名前10%）的存在相关。
在这个社区居住的老年人样本中，黑人、老年人和功能受损者的D - 二聚体水平显著更高。种族方面的研究结果尤为显著，即使在控制了吸烟和其他已知与血栓形成相关的因素后仍然存在，且不受社会因素介导。这一结果可能有助于我们理解这些人群中血栓形成事件水平升高的原因。
