Tip of the Day

January 23, 2008 — One of the largest studies ever to link exercise capacity to mortality risk should motivate physicians to pay as much attention to patients' exercise capacity as they do other major risk factors, researchers say [1]. Their study of older male veterans suggests that the adjusted risk of dying was reduced by 13% for every 1 metabolic equivalent (MET) increase in exercise capacity; men with the greatest exercise capacity reduced their mortality risk by 70%.

"For a little bit of investment you get a lot of a return," lead author on the study, Dr Peter Kokkinos (Veterans Affairs [VA] Medical Center, Washington, DC) told heartwire. "In a time where health insurance in this country is going through the roof, we could do something like walk for thirty minutes a day and reap major benefits. "For god's sake, if we could walk on the moon we can certainly walk on earth."

Their study appears in an early online edition of Circulation,
January 22, 2008.

Kokkinos and colleagues followed 15,660 male veterans with and without cardiovascular (CV) disease who had completed an exercise treadmill test at study outset. More than 40% of veterans participating in the study were black. Baseline exercise capacity for the entire group was divided into quartiles and assessed in relation to all-cause mortality over a mean of 7.5 years.

Fitness reduces death-risk in dose-response fashion

Kokkinos et al report that every 1-MET increase was associated with a reduction in mortality that ranged from 12% in white participants to 15% in black participants, after adjusting for age, body mass index (BMI), CV risk factors, and CV medications. Compared to veterans in the lowest fitness category (< 5 METS), those in the highest exercise capacity (> 10 METS) had a 70% lower risk of all-cause death. Even men in the moderate fitness category (7.1 - 10 METs) had a 50% lower death rate than men with the lowest fitness capacity.

To heartwire, Kokkinos emphasized that the study extends findings from other studies that have largely been conducted in white subjects, from higher socioeconomic classes, to a mixed race, lower socioeconomic group who may not always have access to the best, most expensive, medical care.

"No one study has all the answers, but this study fills in a lot of blanks," Kokkinos said. "The major finding is that for all sorts of people, as one increases his exercise capacity based on an exercise treadmill test, there is an inverse drop in risk in a dose-response fashion. And whether you looked at blacks versus whites, or those with heart disease versus those with no heart disease, those taking beta blockers or no beta blockers, the drop can range anywhere from
12 - 15%."

The authors point out that treadmill tests is a "standardized procedure used throughout the world," but physicians may under-estimate its prognostic capacity. The study results also underscore, once again, the importance and pay-off of regular exercise. Those pay-offs may be particularly relevant in a group that, studies show, frequently cannot afford expensive medications, health club memberships, or even foods that would help improve their cardiovascular risk profile. Daily walking, by contrast, is free.

"People are people, and we all get caught up in the excuse, 'I can't exercise I don't have time,'" Kokkinos commented. "But everyone needs to get involved to get this nation going again, because we are the fattest nation, the most sedentary nation in the world. And we need to do something about it."

Source:

Kokkinos P, Myers J, Kokkinos JP, et al. Exercise capacity and mortality in black and white men. Circulation 2008; DOI: 10.1161/CIRCULATIONAHA.107.734764. Available at: http://circ.ahajournals.org.