September 21, 2023
Association of Daily Step Counts With All-Cause Mortality and Cardiovascular Events
Journal of the American College of Cardiology
TAKE-HOME MESSAGE
- This large meta-analysis sought to establish a relationship between daily “step counts” and the risk of all-cause cardiovascular mortality. The results showed that between 2600 and 2800 steps per day significantly lowered the risk of cardiovascular disease and mortality, with a dose-dependent response up to 8800 steps. Additional benefits were observed for increments from a low to intermediate or high cadence of steps
- This meta-analysis suggests that as little as 2600 steps per day can significantly reduce the risk of cardiovascular disease and mortality, with higher cadence of steps offering further benefits. These findings can be used to advise patients on exercise options and optimal use of health tracking devices.
– Timothy Overton, MD, MPH
Written by Peter Lin MD, CCFP
What is the least number of steps required per day to get a cardiovascular benefit?
We have all heard that people should take 10,000 steps per day as this will help reduce cardiovascular (CV) disease and mortality. However, often, this number sounds too high. Hence, what is the minimum number of steps that a person can take in a day and still get benefits? If the number of steps is reasonable, we could get more of our patients walking.
This study examined the data from 111,309 people from 12 studies evaluating the association of step counts and CV event rates. The authors used 2000 steps per day as the baseline comparator. They found that, with 2517 steps per day, there was an 8.0% statistical reduction in all-cause mortality (aHR, 0.92; 95% CI, 0.84–0.999) and, with 2735 steps per day, there was an 11% — statistically significant — reduction in CV events. Therefore, with just 500 to 700 extra steps, there is a measurable reduction in mortality and CV events. Now, even to the most sedentary person that sounds very doable.
There was a dose–response curve, so the more steps taken, the better the reductions in CV events. At 8763 steps per day, there was a 60% reduction in mortality (aHR, 0.40; 95% CI, 0.38–.43). However, with more than 8763 steps, there is still a reduction in mortality, but it is no longer statistically significant. For CV events, 7126 steps per day led to a 51% reduction (aHR, 0.49; 95% CI, 0.45–0.55), and, with more steps, the reduction increased but was no longer statistically significant. Now, this could mean that more steps were no longer useful or that, in these studies, there were fewer and fewer people who took that many steps, and hence, there were not enough people to be able to see a statistical benefit.
When the researchers looked at cadence (the number of steps taken per minute), the higher the cadence the better the benefit.
Sensors worn on the hips had the best correlation to event reductions. This might be because the hip-worn sensors truly measured your steps, whereas the wrist-worn sensors could just be measuring arm movement.
This study did not tell us whether the steps accumulated all day or whether they were taken in dedicated time frames. That would be of great interest because nowadays experts say that sitting for extended periods of time and not moving is the real culprit. So perhaps steps spread throughout the day might be better than all the steps compressed into 1 hour.
If the steps are spread out, then the leg muscles are constantly turned on, which means that the blood vessels are constantly dilated to supply blood flow to the muscles. Dilated vessels mean less pressure, and the heart has an easier time to pump because there is less resistance. Perhaps future studies can look at how the steps are spread throughout the day to determine whether there is a difference associated with the timing of walking.
For now, our advice to our patients will be music to their ears: No longer do you have to hit 10,000 steps per day – just take at least 2700 steps per day and you will get some benefit with regard to death and CV events. However, if you can take more, then you will be rewarded with even fewer events and increased longevity. Not a bad sales pitch.
Abstract
BACKGROUND
The minimal and optimal daily step counts for health improvements remain unclear.
OBJECTIVES
A meta-analysis was performed to quantify dose-response associations of objectively measured step count metrics in the general population.
METHODS
Electronic databases were searched from inception to October 2022. Primary outcomes included all-cause mortality and incident cardiovascular disease (CVD). Study results were analyzed using generalized least squares and random-effects models.
RESULTS
In total, 111,309 individuals from 12 studies were included. Significant risk reductions were observed at 2,517 steps/d for all-cause mortality (adjusted HR [aHR]: 0.92; 95% CI: 0.84-0.999) and 2,735 steps/d for incident CVD (aHR: 0.89; 95% CI: 0.79-0.999) compared with 2,000 steps/d (reference). Additional steps resulted in nonlinear risk reductions of all-cause mortality and incident CVD with an optimal dose at 8,763 (aHR: 0.40; 95% CI: 0.38-0.43) and 7,126 steps/d (aHR: 0.49; 95% CI: 0.45-0.55), respectively. Increments from a low to an intermediate or a high cadence were independently associated with risk reductions of all-cause mortality. Sex did not influence the dose-response associations, but after stratification for assessment device and wear location, pronounced risk reductions were observed for hip-worn accelerometers compared with pedometers and wrist-worn accelerometers.
CONCLUSIONS
As few as about 2,600 and about 2,800 steps/d yield significant mortality and CVD benefits, with progressive risk reductions up to about 8,800 and about 7,200 steps/d, respectively. Additional mortality benefits were found at a moderate to high vs a low step cadence. These findings can extend contemporary physical activity prescriptions given the easy-to-understand concept of step count. (Dose-Response Relationship Between Daily Step Count and Health Outcomes: A Systematic Review and Meta-Analyses; CRD42021244747).