Exposure to high levels of aircraft noise near busy international airports has been linked to higher risk of heart disease and strokes, according to the Chicago-Tribune. The link was found after two separate studies were conducted in Britain and the United States.

The researchers in London studied noise and hospital admissions near Heathrow airport in London, and another team studied data on six million Americans that live near 89 different U.S. airports.

The Heathrow study found the risks were 10 to 20 percent higher in areas with the highest levels of aircraft noise compared to areas with the least amount of noise.

"Aircraft noise exposure is not just a cause of annoyance, sleep disturbance, and reduced quality of life" but may also increase sickness and death from heart disease, Stephen Stansfeld, a professor at Queen Mary university of London, said.

Some experts say the study raises important issues, but doesn't establish a causal link.

"Both of these studies are thorough and well-conducted," Kevin McConway, a professor of applied statistics at Britain's Open University, said. "But, even taken together, they don't prove that aircraft noise actually causes heart disease and strokes."

Discussions regarding possible expansion plans for London's airport have been on and off the table for many decades due to increased travel demands.

"The exact role that noise exposure may play in ill health is not well established," Anna Hansell, of Imperial College London, said. "However, it is plausible that it might be contributing, for example by raising blood pressure or by disturbing people's sleep."

Policy decisions need to take account of potential health related concerns, including possible effects of environmental noise on cardiovascular health," the researchers wrote.

The studies, which found people living with the highest level of aircraft noise had increased risks of stroke, coronary heart disease and other cardiovascular disease, was published in the British Medical Journal (BMJ).