Randomised double-blind placebo-controlled trial of aspirin in primary prevention of CVD events or dementia in the aged.

心血管疾病最重要的危险因素是年龄。所有75岁的男性在未来5年内中风或心脏病发作的风险为10-15%。低剂量阿司匹林已被证明可以预防已经患过中风和心脏病的人进一步中风和心脏病发作。它也被证明可以保护那些没有心脏病发作或中风但风险增加的人。既然老年人的风险增加，为什么我们需要在这个特殊的群体中进行试验？原因是以前的预防试验中纳入的老年患者相对较少。此外，虽然老年人可能从治疗中获益最多，但他们也有最大的损失，因为他们更有可能遭受副作用。阿司匹林通过阻止血管中血栓的形成来预防心脏病发作。这也意味着服用它的人有出血的倾向。因此，虽然它可以防止由于血栓引起的中风，但它也可能增加出血引起中风的风险。肠道出血是另一个主要问题，因为阿司匹林往往会侵蚀胃粘膜。肠道轻微出血也会降低血液携氧能力，这可能会加剧与衰老相关的其他疾病，例如心力衰竭。痴呆症可能是由小血管或大血管中的反复血栓引起的。痴呆症是老年人的一个特殊问题，影响85岁奥尔兹中的10%。这是生活质量下降的一个主要原因，也是社会的一个重大代价。阿司匹林可以减少这种疾病的进展，从而维持个人及其家庭的生活质量（QOL）。随着年龄的增长，我们的寿命在减少。这是不言而喻的。因此，增加寿命的可能性降低，疾病对生活质量产生不利影响的可能性变得更加重要。因此，预防导致住院的非致命性中风可能比预防致命性中风更重要。因此，将评估QOL。

The single most important risk factor for cardiovascular disease is age. All men aged 75 years have a 10-15% risk of having a stroke or heart attack in the next 5 years. Low dose aspirin has been shown to prevent further strokes and heart attacks in people who have already had one. It has been also shown to protect people who have not had a heart attack or stroke but who are at increased risk. Given that the elderly are at increased risk why do we need to do a trial in this particular group? The reason is that relatively few elderly patients were included in the previous prevention trials. Also while the elderly may have the most to gain from treatment, they also have the most to lose because they are more likely to suffer from side-effects. Aspirin prevents heart attacks by stopping clots forming in blood vessels. This also means that people taking it have an increased tendency to bleed. Thus though it may prevent strokes due to clots it may also increase the risk of strokes caused by bleeding. Bleeding from the gut is another major problem as aspirin tends to erode the lining of the stomach. Minor bleeding from the gut can also lower blood oxygen carrying capacity which may exacerbate other diseases associated with ageing, e.g. heart failure. Dementia may be caused by repeated clots in small or large vessels. Dementia is a particular problem in the elderly affecting 10% of 85 year olds. It is a major cause of loss of quality of life and a significant cost to the community. Aspirin may reduce the progression of such a disease leading to a maintained quality of life (QOL) for individuals and their families. As our age increases our years of life remaining decreases. This is self-evident. Thus the potential to add years to life reduces and the potential of diseases to adversely affect quality of life becomes more important. Thus it may be more important to prevent a nonfatal stroke that leads to institutionalisation than a fatal stroke. Hence QOL will be assessed.