Is poor fitness worse than smoking, heart disease, and diabetes?
What was studied?
"What is the association between cardiorespiratory fitness and long-term mortality?"
These researchers retrospectively looked at the cardiorespiratory fitness (CRF) of patients who were referred for exercise treadmill testing (ETT). CRF was gauged based upon the maximal METs achieved by patients during the ETT. (For an explanation of METs in CRF, go here.)
Who were the patients?
There were 122,007 patients evaluated from a non-hospital clinic with records pulled from January 1, 1991, to December 31, 2014. Roughly 60% of the patients were male, and patients averaged around 53 years old (+/-13yrs).
Many of the patients had comorbid conditions (e.g., CAD, Coronary Bypass/Heart Surgery, Elevated Lipids, Diabetes, etc..). Specifically, around 44% of patients had elevated blood pressure, and approximately 46% of patients were current smokers. You can see all the details below.
JAMA Netw Open. 2018;1(6):e183605. doi:10.1001/jamanetworkopen.2018.3605
So, who survived the most over the median 8.4yr follow-up period?
Around 11.2% of all the patients (13,637) died from any cause (aka "all-cause mortality") during the median 8.4yr follow-up.
One of the key findings was that there was a significant and incremental reduction in all-cause mortality with increasing CRF. In fact, elite CRF performers had the best survival of any group (even better than the high performers).
JAMA Netw Open. 2018;1(6):e183605. doi:10.1001/jamanetworkopen.2018.3605
Fancy Statistics Warning: COX Proportional Hazards Regression
Feel free to skip this section if statistics make your head spin. Go right on down to my 3 thoughts to ponder!
So the significant finding was that an "…incremental reduction in all-cause mortality was associated with increased performance when compared to low performers."
There was an 80% reduction in risk of death in elite performers compared to the lowest performers (HR 0.20; 95% CI, 0.16-0.24; P<0.001.). The flipside is that, when compared to elite performers, the low performers were 5 times more likely to die of any cause over the study period (HR 5.04, 95% CI, 4.10-6.20; P<0.001).
There was a 1.4 times greater risk of death in below average performers compared to above average performers (HR 1.41; 95% CI, 1.34-1.49; P<0.001).
There was even a 23% decreased risk of death in elite performers compared to high performers (HR 0.77; 95%CI 0.63-0.95; P =0.02). This risk reduction was more significant if the patient was over 70 years old, or the patient had elevated blood pressure.
Low CRF actually carried the risk that was equal to or greater than traditional risk factors. There was a 1.3 times greater risk of death in low CRF when compared to coronary artery disease (CAD; HR 1.29; 95% CI 1.24-1.35; P<0.001).
There was a 1.4 times greater risk of death in low CRF when compared to smoking (HR 1.41; 95% CI 1.36-1.46; P<0.001.
There was a 1.4 times greater risk of death in low CRF when compared to diabetes (HR 1.40; 95% CI, 1.34-1.46; P<0.001).
The 3 thoughts I want us all (regular joes, coaches, clinicians) to leave pondering.
These are quotes copied from the discussion section of the article referenced below for this post.
Let this sink in…
Poor cardiovascular fitness might be worse for your health than smoking. (This seems quite unfortunate for smokers with poor cardiovascular health.)
"When compared with the lowest performers, elite performance was associated with an 80% reduction in mortality risk. Also, the adjusted mortality risk of reduced performance was comparable to, if not significantly greater than, traditional clinical risk factors, such as CAD, diabetes, and smoking (Figure 2C)."
Now let this sink in…
Your cardiovascular health and fitness is modifiable, which means your risk is modifiable. Want to live a better life? Take care of your cardiovascular fitness.
"These findings not only reinforce the large collective body of evidence correlating aerobic fitness with numerous health benefits but also illustrate the importance of aerobic fitness as a powerful, modifiable indicator of long-term mortality."
Last, but not least…
If your doctor or healthcare provider is not telling you that your cardiovascular fitness should be a priority in your life… then I am. It should be a priority in your life, so long as you want a higher chance of having a longer one with a better quality of living.
"Cardiorespiratory fitness is a modifiable indicator of long-term mortality, and health care professionals should encourage patients to achieve and maintain high levels of fitness."
Wondering how to get started with your cardiovascular fitness?
Check out my 4-part series on cardiovascular training, starting here with Part 1.
Or you can schedule an appointment with me where we can discuss your history, nutrition/lifestyle, relevant labs, and possible medications or supplements to optimize your heart health and minimize your cardiovascular risk.
Reference: Mandsager, K., Harb, S., Cremer, P., Phelan, D., Nissen, S. E., & Jaber, W. (2018). Association of cardiorespiratory fitness with long-term mortality among adults undergoing exercise treadmill testing. JAMA network open, 1(6), e183605-e183605.