Heart Rate Recovery and Cancer Risk: Prospective Cohort Study.

This study aims to determine the association between 2-minute heart rate recovery (HRR) and cancer risk. Each participant (5379 women; 8485 men) provided HRR obtained from treadmill tests. The outcome was site-specific cancer. Over 9 years of follow-up, 630 cancer events (258 women) were accrued. Slower HRR was associated with increased thyroid cancer risk in women ( P for trend = .0121) and colorectal cancer risk in men ( P for trend = .0034). The lowest HRR (<13 bpm) had higher hazards of thyroid cancer (hazard ratio [HR] = 2.20; 95% CI = 1.28-3.77) in women and colorectal cancer (HR = 3.08; 95% CI = 1.32-7.15) in men. In women, slower HRR and lower proportions of heart rate recovery (PHRR) were associated with higher hazards of thyroid cancer in women and metabolically related cancers (liver and colorectal) in men. Slower HRR and lower PHRR were independent risk factors for thyroid cancer in women and metabolically related cancers in men.