Romero Juan Pablo, Benito-León Julián, Louis Elan D, Bermejo-Pareja Félix
Department of Neurology, University Hospital "12 de Octubre", Madrid, Spain.
Department of Neurology, University Hospital "12 de Octubre", Madrid, Spain Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Spain Department of Medicine, Complutense University, Madrid, Spain.
J Alzheimers Dis. 2014;40(2):465-73. doi: 10.3233/JAD-132048.
Previous studies have shown that Alzheimer's disease (AD) is associated with a reduced risk of cancer. However, most studies exclude those with undiagnosed dementia. The only way to overcome this methodological issue is to examine all the participants or to screen the population for symptoms of dementia with a validated instrument and confirm any suspected dementia patients with a clinical examination (i.e., a two-phase investigation method). We used this methodology to estimate whether cancer-specific mortality is associated with AD and other types of dementia in a prospective population-based study (NEDICES) involving 5,278 elderly people. Community-dwelling subjects with and without dementia were identified and followed for a median of 12.5 years, after which the death certificates of those who deceased were examined. A total of 1,976 (47.1%) died, including 277 who had possible or probable AD and 126 with non-AD dementia. Cancer was reported significantly less often in those with possible or probable AD (5.8%) or non-AD dementia (6.3%) than in those without dementia (26.5%). In an unadjusted Cox model, hazard ratio (HR) of cancer-specific mortality in participants with AD = 0.45 (p = 0.002) and HR in participants with non-AD dementia = 0.62 (p = 0.179) when compared to the non-demented group. In a Cox model that adjusted for a variety of demographic factors and co-morbidities, HRs of cancer-specific mortality in participants with AD = 0.50 (p = 0.028) and 0.97 (p = 0.942) in non-AD dementia. This study provides further evidence of an inverse association between cancer and AD.
先前的研究表明，阿尔茨海默病（AD）与患癌风险降低有关。然而，大多数研究将未确诊痴呆的人群排除在外。克服这一方法学问题的唯一途径是检查所有参与者，或使用经过验证的工具对人群进行痴呆症状筛查，并通过临床检查确认任何疑似痴呆患者（即两阶段调查方法）。在一项涉及5278名老年人的基于人群的前瞻性研究（NEDICES）中，我们采用这种方法来评估癌症特异性死亡率是否与AD及其他类型的痴呆相关。识别出有和没有痴呆的社区居住受试者，并对他们进行了为期12.5年的随访，之后检查了死亡者的死亡证明。共有1976人（47.1%）死亡，其中包括277名可能患有或很可能患有AD的患者以及126名患有非AD痴呆的患者。据报告，可能患有或很可能患有AD的患者（5.8%）或非AD痴呆患者（6.3%）患癌的频率明显低于没有痴呆的患者（26.5%）。在未调整的Cox模型中，与非痴呆组相比，患有AD的参与者癌症特异性死亡率的风险比（HR）=0.45（p = 0.002），患有非AD痴呆的参与者的HR = 0.6（p = 0.179）。在一个针对各种人口统计学因素和合并症进行调整的Cox模型中，患有AD的参与者癌症特异性死亡率的HR = 0.50（p = 0.028），非AD痴呆患者的HR为0.97（p = 0.942）。这项研究进一步证明了癌症与AD之间存在负相关。
