CDC Image: Cardiorespiratory Fitness
MedicalResearch.com Interview with:
Susan G. Lakoski, M.D.
Assistant Professor of Medicine, Hematology/Oncology DivisionDepartment of Medicine Director, Cardiovascular Prevention Program for Cancer PatientsVermont Cancer Center, Division of Hematology/OncologyUniversity of Vermont, BurlingtonCo-Investigators from Cooper Center Longitudinal Study
Cooper Institute in Dallas, Texas
Medical Research: What is the background for this study? What are the main findings?
- High cardiorespiratory fitness (CRF) is associated with 55% reduction in lung cancer and 44% reduction in colorectal cancer in white men. These results were similar even among non-smokers.
- High cardiorespiratory fitness is associated with a one-third risk reduction in all cancer-related deaths among men who developed lung, colorectal, or prostate cancer at age 65 years or older compared with low cardiorespiratory fitness.
- High cardiorespiratory fitness is associated with a two-thirds reduction in cardiovascular death compared with low cardiorespiratory fitness among men who developed cancer at age 65 years or older.
- There is an strong inverse relationship association between fitness and subsequent diagnosis of incident lung and colorectal cancer, but not prostate cancer, in white men.
MedicalResearch.com: What should patients and clinicians take away from this report:
A) The relationship between fitness and prostate cancer risk is controversial. It is possible that men with higher cardiorespiratory fitness may be more likely to undergo more frequent preventive health care screening and/or detection visits and, thus, had greater opportunity to be diagnosed as having localized prostate cancer relative to men of lower cardiorespiratory fitness. Importantly, men who developed prostate cancer in the current study, had a lower risk of ultimately dying of cancer or cardiovascular disease if ‘fit’ prior to disease onset. This speaks to the importance of being ‘fit’ in mid-life to improve survival even if a man ultimately develops lung, prostate, or colorectal cancer later in life.
B). Among the men who developed cancer, those who were more fit at middle age had a lower risk of dying from all the three cancers studied, as well as cardiovascular disease. Even a small improvement in fitness (by 1-MET) made a significant difference in survival ─ reducing the risks of dying from cancer and cardiovascular disease by 10 and 25 percent, respectively.
EXAMPLE of what a 1-MET difference equates to:
Running, 5 mph (12 min/mile) = 8 METs
Running, 5.2 mph (11.5 min/mile) = 9 MET
C) Our findings indicate that cardiorespiratory fitness provides cancer risk prediction information beyond these established lifestyle risk factors. These findings provide support for the utility of cardiorespiratory fitness assessment (via a maximal exercise treadmill test) in preventive health care settings and possibly following a diagnosis of cancer.
The benefits of measuring fitness include:
1) Provide accurate and stable marker of exercise exposure and dose.
2) Measurements can be reproducibly measured over time.
3) Normative values are available to compare fitness levels of patients to the general population for counseling.
4) Allows clinicians to prescribe personalized exercise training goals for patients.
Medical Research: What recommendations do you have for future research as a result of this study?
Dr. Lakoski: Future studies are needed to test these results across all major cancers in men and women and also address how much an individual must change their fitness to see cancer prevention benefit.
Lakoski SG, Willis BL, Barlow CE, et al. Midlife Cardiorespiratory Fitness, Incident Cancer, and Survival After Cancer in Men: The Cooper Center Longitudinal Study. JAMA Oncol. Published online March 26, 2015. doi:10.1001/jamaoncol.2015.0226.
MedicalResearch.com Interview with: Susan G. Lakoski, M.D. (2015). Cardiorespiratory Fitness May Decrease Cancer Risk and Improve Survival