As aerobic fitness increases, the risk of chronic kidney disease (CKD) progressively decreases suggesting a protective role for exercise, according to a new study of male veterans.
“The findings of the present study demonstrate that health benefits associated with higher exercise capacity also extend to lowering the risk of developing CKD,” stated Peter Kokkinos, PhD, of Veterans Affairs Medical Center in Washington DC, and colleagues.
The investigators prospectively assessed peak exercise capacity for 5,812 male veterans at the center using a standard treadmill test. The men were referred for exercise testing for clinical reasons.
All participants were free of CKD stage 3 and above at baseline with an estimated glomerular filtration rate of 60 mL/min per 1.73 m2 or higher. CKD developed in 1,010 men (17%) during follow-up.
According to results published in Mayo Clinic Proceedings, the risk of CKD declined by 22% with every 1 metabolic equivalent (MET) increase in exercise capacity. Compared to the least fit individuals, the odds of CKD were 13%, 45%, and 58% lower in the low-, moderately-, and high-fit groups, respectively.
Researchers adjusted the fitness groupings for age. They also adjusted their models for CKD predictors, such as race, diabetes, hypertension, dyslipidemia, alcoholism, glucose-lowering medication, and lipid-lowering medication.
Men with lower GFR may be deficient in vascular density and recruitment, the researchers suggested. Also, a significant number of the veterans had a high body mass index and diabetes. Insulin resistance, dyslipidemia, and hypertension may contribute to vascular stiffness and systemic inflammation, setting the stage for CKD.
By contrast, physically active men have greater capillary recruitment during exercise, which likely corresponds to a greater renal reserve and a lower likelihood of CKD.
Starting an aerobic exercise routine is reasonable for many men with their doctors’ permission, the investigators noted: “The average exercise capacity of approximately more than 6.5 METs necessary to realize these health benefits is achievable by many middle-aged and older men by daily exercises, such as brisk walking.”