癡呆癥常見的危險因素包括年齡、家族史和遺傳病史。但最新研究指出，除此之外，還有另外一個因素可能會影響患癡呆癥的可能性：居住在車水馬龍的主干道旁邊。加拿大一項新研究發現，由于空氣中的污染物可能通過血液進入大腦，引發神經系統病變，住在交通繁忙地段附近的人患癡呆癥的風險更高。

Living near a main road increases the risk of dementia, the first major research into air pollution and disease has shown.
首項研究空氣污染與疾病關系的重要調查發現，住在主干道旁邊有可能增加患癡呆的風險。

A decade-long study of 6.6 million people, published in The Lancet, found that one in 10 dementia deaths in people living within 50 metres of a busy road was attributable to fumes and noise.
該研究時長超過十年，參與樣本超過660萬人并發表在醫學期刊《柳葉刀》上面。研究結果表明，在居住在嘈雜路段50米范圍內的癡呆癥死亡患者中，有十分之一的患者病因可歸因為尾氣和噪音。

There was a linear decline in deaths the further people lived away from heavy traffic.
結果表明，離車水馬龍的道路越遠，他們的死亡率越低，且呈直線下降。

Air pollution is already known to contribute to the deaths of around 40,000 people in Britain each year by exacerbating respiratory and heart conditions, while previous research showed emissions can cause brain shrinkage.
我們已經知道空氣污染可引起呼吸系統及心臟健康的惡化，每年造成近乎4萬英國人死亡。此前的研究還表明，尾氣排放會引起大腦萎縮。

But the new study by Canadian public health scientists is the first to find a link between living close to heavy traffic and the onset of dementia, a discovery described as "plausible" and "impressive" by British experts.
然而，加拿大公共健康方面的科學家們最新的研究，卻第一次找到住在馬路旁和患癡呆幾率上升之間的關系。這次發現被英國科學家們稱之為“可信的”及“令人震驚的”。

Dr Hong Chen, the lead author from Public Health Ontario, said:
本次研究結果的首席作者、加拿大安大略省公共醫療局陳宏（音）博士表示：

"Our study suggests that busy roads could be a source of environmental stressors that could give rise to the onset of dementia."
“我們的研究結果表明繁忙的交通有可能成為一種加大患癡呆幾率的環境壓力源。”

"Increasing population growth and urbanisation has placed many people close to heavy traffic, and with widespread exposure to traffic and growing rates of dementia, even a modest effect from near-road exposure could pose a large public health burden."
“人口增長及城市化讓許多人住在繁忙路段附近，大范圍接觸到繁忙交通，老年癡呆病患上升。住在路邊的一般影響也有可能嚴重危及公共健康。”

"More research to understand this link is needed, particularly into the effects of different aspects of traffic, such as air pollutants and noise. Around 850,000 people suffer from dementia in Britain, and it is now the leading cause of death for both men and women."
“我們需要做更多研究證明這樣的聯系，特別是對交通各種不同方面的影響，比方說空氣污染物及噪聲。在英國，約85萬人身患癡呆。癡呆現在已經是人們死亡的主要原因之一了。”

There has been concern that air pollution could be driving neurodegenerative conditions for many years.
有擔心者表示，空氣污染很有可能導致多年的神經退化。

Last year British scientists discovered tiny magnetic particles produced by car engines and brakes in the brains of people diagnosed with Alzheimer's disease.
去年，英國科學家在阿爾茲海默癥患者的腦部發現了汽車發動機和剎車系統排放出的磁粒子。

In the new study, the team tracked all adults aged between 20 and 85 living in Ontario for more than a decade from 2001 to 2012. They used postcodes to determine how close people lived to a main road and analysed medical records to see if they went on to develop dementia, Parkinson's disease or multiple sclerosis.
最新的這次研究從2001年到2012年跨越10年，研究人員追蹤了住在安大略省的人們，年齡跨度涵蓋20歲到85歲。他們用郵編來確認大家住得離主干道有多近，并進一步分析他們的醫療記錄，分析他們會不會得老年癡呆、帕金森或者是多發性硬化。

Over the study period, more than 243,000 people developed dementia, 31,500 people developed Parkinson's disease and 9,250 people developed multiple sclerosis.
在研究過程中，超過24.3萬人患上了老年癡呆，約3.15萬人患上了帕金森，而有9250人得了多發性硬化。

While there was no association between living near a road and Parkinson's disease or multiple sclerosis, dementia risk reduced as people lived further from a main road, with a 7 percent higher risk in developing dementia among those living within 50 metres; a 4 percent higher risk at 50-100 metres and a 2 percent higher risk at 101-200 metres.
目前還沒有找到住得離繁忙路段遠近和患帕金森或多發性硬化幾率的聯系，然而人們住得離主干道越遠，患老年癡呆的幾率就會下降。這些住所離主干道50米之內的人患癡呆的幾率會高7%，50-100米內，幾率會高4%，而距離在101-200米內幾率會高2%。

After 200 metres there was no increase.
距離超過兩百米后，就幾乎沒有什么顯著的影響了。

Researchers believe that noise of traffic may also play a role in the raised risk as well as other urban pollution, which is often present near busy roads.
研究者相信交通噪音及其他城市污染也很有可能是導致風險增加的原因。這在嘈雜路段非常常見。

英文來源：每日電訊報
翻譯：鴻嘉（中國日報網愛新聞iNews譯者）
編審：yaning