Abstract 4348: Cardiorespiratory fitness levels in men who develop prostate cancer and its association with all-cause mortality
Authors: Reiter-Brennan Cara , Dzaye Omar , Al-Mallah Mouaz H. , Dardari Zeina , Brawner Clinton A. , Lamerato Lois E. , Keteyian Steven J. , Ehrman Jonathan K. , Visvanathan Kala , Blaha Michael J. , Marshall Catherine Handy 
Published: September 2020

Background: Cardiorespiratory fitness (CRF) is associated with a reduction in both cancer- and cardiovascular-specific mortality. In men however, little is known about the impact of pre-diagnostic CRF on mortality after prostate cancer. We hypothesized that among men with prostate cancer, low levels of CRF, measured prior to diagnosis, are associated with a higher risk of all-cause mortality.

Methods: From the Henry Ford FIT Project, a cohort of 37,730 men who underwent clinically-indicated exercise stress test from 1991 through 2009, we identified 1,440 men who developed prostate cancer after stress test. CRF was measured in peak metabolic equivalents of task (METs) and categorized as less than 6, 6 to 9, 10 to 11, and at least 12 (reference). Multivariable Cox proportional hazard models were developed to evaluate the association between CRF, measured prior to prostate cancer diagnosis, and all-cause mortality. Models were adjusted for age at prostate cancer diagnosis (baseline), race, BMI, current aspirin and statin use, smoking history, hypertension, diabetes, prior cardiovascular disease (myocardial infarction and heart failure), time from stress test to prostate cancer diagnosis, and cancer stage (local, regional, distant) at diagnosis.

Results: Mean age at time of stress test was 61 +/- 9 yr (57% white, 39% black), with 7 (+/-4) yrs of follow up after prostate cancer diagnosis. 81% of men were diagnosed with localized prostate cancer; 15% with regional disease, and 2% with distant metastatic disease. Mean time from stress test to diagnosis was 6 +/- 5 yrs. Mean METs achieved was 9 (+/- 3). Patients with low fitness (METs less than 6) before diagnosis had 2.6 times the risk of all-cause mortality (95% CI 1.6-4.2) compared to those with high fitness (METS at least 12). Those with CRF of 6-9 METs had 1.9 times the risk (95% CI 1.2-3.0). The risk of mortality was not different between the two highest fitness groups (P= 0.71; P for trend across all fitness groups less than 0.01). Results were similar when stratified by race.

Conclusion: Low CRF prior to the diagnosis of prostate cancer in men is associated with a higher risk of all-cause mortality. This study highlights the prognostic importance of fitness even before a cancer diagnosis.

Citation Format: Cara Reiter-Brennan, Omar Dzaye, Mouaz H. Al-Mallah, Zeina Dardari, Clinton A. Brawner, Lois E. Lamerato, Steven J. Keteyian, Jonathan K. Ehrman, Kala Visvanathan, Michael J. Blaha, Catherine Handy Marshall. Cardiorespiratory fitness levels in men who develop prostate cancer and its association with all-cause mortality [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 4348.