A new test which predicts a person’s risk of dying over a 10-year period has been developed – based on their ability to run on treadmill.
Scientists from John Hopkins University have made a formula dubbed the Fit Treadmill Score which determines a person’s long-term death risk by testing subjects as the speed and incline on the treadmill is increased.
“The notion that being in good physical shape portends lower death risk is by no means new,” said lead investigator Haitham Ahmed, a cardiologist fellow at John Hopkins University.
“But we wanted to quantify that risk precisely by age, gender and fitness level, and do so with an elegantly simple equation that requires no additional fancy testing beyond the standard stress test.”
Other exercise-based tests do exist, but they can only measure a person’s short-term risk of death.
This new test described in the March 2 issue of the journal Mayo Clinic Proceedings can look at the risk over 10 years.
John Hopkins cardiologists developed the formula by analysing data from 58,000 heart stress tests. It factors in age, gender, peak heart rate and ability to tolerate physical exertion.
Michael Blaha, director of clinical research at John Hopkins, said: “The Fit Treadmill Score is easy to calculate and costs nothing beyond the cost of the treadmill test itself.
“We hope the score will become a mainstay in cardiologists and primary clinicians’ offices as a meaningful way to illustrate risk among those who undergo cardiac stress testing and propel people with poor results to become more physically active.”
The study looked at people aged 18 to 96 who underwent standard exercise stress tests between 1991 and 2009 to evaluate chest pain, shortness of breath or dizziness. The researchers then tracked how many of them at each fitness level died from any cause over the next decade.
The results showed that among people of the same age and gender, fitness was the most powerful indicator of death risk-a finding that underscores the importance of heart and lung fitness.
Patients who scored 100 or higher had a 2% risk of dying over the next 10 years, while those with scores between 0 and 100 faced a 3% chance of dying. Those with lower than negative 100 had a 38% risk of dying.
As well as the report, researchers have created a chart depicting death risk by age, gender and fitness level, which can be printed on placards for use in doctor’s offices.
For example, a 45-year-old woman with a fitness score in the bottom fifth percentile is estimated to have a 38% risk of dying over the next decade, compared with 2 % for a 45 year old woman with a top fitness score.