What’s the news item mainly about?

(2)A medical study in Britain says people living in areas which have very high level of aircraft noise would appear to be at greater risk of stroke or heart disease. Researchers studied more than 3. 5 million people living near Heathrow Airport in West London.
    The researchers find that in the areas where noise from planes was loudest, the risk of being admitted to hospital or dying from a stroke or heart disease was between 10% and 20% higher. Writing in the British medical journal, the author suggested this could be because the startling and annoying effect of the noise was leading to raise blood pressure.(3)The team was at pains to point out that the possible link between aircraft noise and illness was far less significant than the factors that are known to have influences on the risk such as smoking. But the researchers think the connection should be investigated further and policymakers should take it into account.